@article{RauchBrueckl, author = {Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Achieving Optimal Reactive Power Compensation in Distribution Grids by Using Industrial Compensation Systems}, series = {Electricity}, volume = {4}, journal = {Electricity}, number = {1}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/electricity4010006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-59139}, pages = {78 -- 95}, abstract = {This paper presents a method for integrating industrial consumers owning compensation systems as alternative reactive power sources into grid operating processes. In remuneration, they receive a market-based provision of reactive power. The aim is to analyze the potential of reactive power compensation systems of industrial companies connected to medium-voltage (10 kV-30 kV) AC grids in order to increase the reactive power ability of distribution grids. Measurement methods and reactive power potential results of six industrial companies are presented to characterize the amount and temporal availability of their reactive power potential. The presented approach for using the decentralized reactive power potential is a centralized reactive power control method and is based on optimal power flow (OPF) calculations. An optimization algorithm based on linear programming is used to coordinate a reactive power retrieval tuned to the actual demand. The influencing quantities are the current grid status (voltage and load flow capacity reserves at grid nodes and power lines) and the current reactive power potential of the reactive power sources. The compensation impact of six measured industrial companies on an exemplary medium-voltage grid is shown by an application example.}, language = {en} } @article{KahlKrauseHackenbergetal., author = {Kahl, Matthias and Krause, Veronika and Hackenberg, Rudolf and Ul Haq, Anwar and Horn, Anton and Jacobsen, Hans-Arno and Kriechbaumer, Thomas and Petzenhauser, Michael and Shamonin (Chamonine), Mikhail and Udalzow, Anton}, title = {Measurement system and dataset for in-depth analysis of appliance energy consumption in industrial environment}, series = {tm - Technisches Messen}, volume = {86}, journal = {tm - Technisches Messen}, number = {1}, publisher = {De Gruyter}, doi = {10.1515/teme-2018-0038}, pages = {1 -- 13}, abstract = {To support a rational and efficient use of electrical energy in residential and industrial environments, Non-Intrusive Load Monitoring (NILM) provides several techniques to identify state and power consumption profiles of connected appliances. Design requirements for such systems include a low hardware and installations costs for residential, reliability and high-availability for industrial purposes, while keeping invasive interventions into the electrical infrastructure to a minimum. This work introduces a reference hardware setup that allows an in depth analysis of electrical energy consumption in industrial environments. To identify appliances and their consumption profile, appropriate identification algorithms are developed by the NILM community. To enable an evaluation of these algorithms on industrial appliances, we introduce the Laboratory-measured IndustriaL Appliance Characteristics (LILAC) dataset: 1302 measurements from one, two, and three concurrently running appliances of 15 appliance types, measured with the introduced testbed. To allow in-depth appliance consumption analysis, measurements were carried out with a sampling rate of 50 kHz and 16-bit amplitude resolution for voltage and current signals. We show in experiments that signal signatures, contained in the measurement data, allows one to distinguish the single measured electrical appliances with a baseline machine learning approach of nearly 100\% accuracy.}, language = {en} } @inproceedings{WagnerLehrerFrankeetal., author = {Wagner, Marcus and Lehrer, Tobias and Franke, Markus and Al-Abadi, Ali and Gamil, Ahmed}, title = {A Tank Resonance Model for Power Transformers}, series = {ARWtr 2022 proceedings, 2022 7th Advanced Research Workshop on Transformers (ARWtr): October (23)24-26, 2022, Baiona, Spain}, booktitle = {ARWtr 2022 proceedings, 2022 7th Advanced Research Workshop on Transformers (ARWtr): October (23)24-26, 2022, Baiona, Spain}, publisher = {IEEE}, organization = {Institute of Electrical and Electronics Engineers (IEEE)}, doi = {10.23919/ARWtr54586.2022.9959917}, pages = {7 -- 12}, abstract = {During the factory acceptance test, the sound levels are measured. If the measured sound levels exceed pre-specified values, modifications on the transformer's active part and/or tank need to be conducted. Tank resonance, if occurs, at twice main power frequency and its higher harmonics is one of the main reasons of amplifying the generated sound levels. Therefore, it is preferable to know already in the design stage about the occurrence of the tank resonance and propose reliable tank solutions. The current study presents a newly developed model for calculating the mode shapes and its corresponding eigenfrequencies of the tank.}, language = {en} } @article{WeberHaug, author = {Weber, Karsten and Haug, Sonja}, title = {Ist automatisiertes Fahren nachhaltig?}, series = {TATuP - Zeitschrift f{\"u}r Technikfolgenabsch{\"a}tzung in Theorie und Praxis}, volume = {27}, journal = {TATuP - Zeitschrift f{\"u}r Technikfolgenabsch{\"a}tzung in Theorie und Praxis}, number = {2}, publisher = {Karlsruhe Institute of Technology (KIT)}, doi = {10.14512/tatup.27.2.16}, pages = {16 -- 22}, abstract = {Automatisiertes Fahren st{\"o}ßt derzeit noch auf große Skepsis. Eine disruptive Strategie bei der Einf{\"u}hrung (voll-)automatisierten Fahrens k{\"o}nnte daher auf fehlende Akzeptanz treffen. Um dem zu entgehen, laufen evolution{\"a}re Strategien darauf hinaus, durch die Entwicklung adaptiver Fahrassistenzsysteme Vertrautheit, Vertrauen und damit Akzeptanz bei den prospektiven NutzerInnen zu schaffen. Erste Ergebnisse einer Pilotstudie lassen jedoch Zweifel an der Nachhaltigkeit dieser Strategie aufkommen.}, language = {de} } @misc{Hartweg, type = {Master Thesis}, author = {Hartweg, Johanna}, title = {Analyse des Einflusses verschiedener Arbeitspunkte auf die wirkleistungsabh{\"a}ngige Spannungssensitivit{\"a}t an einem Mittelspannungsnetzknoten}, address = {Regensburg}, doi = {10.35096/othr/pub-5564}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-55648}, school = {Ostbayerische Technische Hochschule Regensburg}, pages = {76}, abstract = {Im Rahmen dieser Arbeit erfolgt die Untersuchung der wirkleistungsabh{\"a}ngigen Spannungssensitivit{\"a}t an den Knoten eines Mittelspannungsnetzstranges. Hierf{\"u}r wird eine Reihe von Arbeitspunkten durch die Variation der Wirkleistungsentnahmen bzw. Einspeisungen an den Netzknoten sowie des Verschiebungsfaktors und der Spannungssollwertvorgabe am Bilanzknoten erzeugt. Die Ergebnisse zeigen eine direkte Abh{\"a}ngigkeit von der Spannung des untersuchten Netzknotens. Hierbei steigt die Sensitivit{\"a}t bei fallenden Spannungswerten. Diese k{\"o}nnen sowohl durch Wirk- und Blindleistungsbelastungen als auch durch eine ver{\"a}nderte Referenzspannung am Umspannwerk bedingt werden. Dar{\"u}ber hinaus liegt eine Beeinflussung durch die Wirkleistungsbelastung und deren Verteilung {\"u}ber den Netzstrang hinweg vor. Je h{\"o}her die Belastung der Leitung bis zum Knoten der Flexibilit{\"a}t ausf{\"a}llt sowie je st{\"a}rker sich die Last hin zu diesem Punkt verlagert, desto h{\"o}her ist die Sensitivit{\"a}t. Dies gilt ebenfalls f{\"u}r Arbeitspunkte mit gleichbleibender Spannung in den betrachteten Knoten. Des Weiteren wird die Anpassung eines multiplen linearen Regressionsmodells vorgenommen. Dieses erm{\"o}glicht eine Absch{\"a}tzung der Sensitivit{\"a}tswerte durch die Kenntnis einiger, die Belastungssituation des Netzes bestimmender Parameter.}, language = {de} } @techreport{GerhardsWeberKlafkaetal., author = {Gerhards, Christoph and Weber, Urban and Klafka, Peter and Golla, Stefan and Hagedorn, Gregor and Baumann, Franz and Brendel, Heiko and Breyer, Christian and Clausen, Jens and Creutzig, Felix and Daub, Claus-Heinrich and Helgenberger, Sebastian and Hentschel, Karl-Martin and von Hirschhausen, Christian and Jordan, Ulrike and Kemfert, Claudia and Krause, Harald and Linow, Sven and Oei, Pao-Yu and Pehnt, Martin and Pfennig, Andreas and Pr{\"a}ger, Fabian and Quaschning, Volker and Schneider, Jens and Spindler, Uli and Stelzer, Volker and Sterner, Michael and Wagener-Lohse, Georg and Weinsziehr, Theresa}, title = {Klimavertr{\"a}gliche Energieversorgung f{\"u}r Deutschland - 16 Orientierungspunkte}, series = {Diskussionsbeitr{\"a}ge der Scinetists for Future ; 7}, journal = {Diskussionsbeitr{\"a}ge der Scinetists for Future ; 7}, doi = {10.5281/zenodo.4409334}, abstract = {Als fairer Beitrag Deutschlands zur Einhaltung der globalen 1,5-Grad-Grenze werden 16 Orientierungspunkte f{\"u}r eine klimavertr{\"a}gliche Energieversorgung vorgestellt. Es wird davon ausgegangen, dass hierf{\"u}r die deutschen energiebedingten CO2-Emissio­nen in etwa 15 Jahren weitgehend auf Null sinken m{\"u}ssen. Energieeinsparung hilft, den notwendigen Ausbau von regenerativen Erzeugungskapazit{\"a}ten zu verringern. Der Verkehrssektor kann ebenso wie die Bereiche Prozess- und Geb{\"a}udew{\"a}rme hier­zu wesentlich beitragen. Die Kernenergie ist mit großen Risiken belastet und kann nicht hinreichend schnell aufgebaut werden. Biomasse in Form von Energie­pflan­zen zu nutzen, ist ineffizient und steht im Konflikt mit anderen Arten der Land­nut­zung. Importe klimaneutral erzeugter Energietr{\"a}ger in sehr großem Umfang er­for­dern extrem große Investitionen im Ausland. Sie sind eine ungesicherte Option auf die Zukunft. Entscheidend ist daher der ausreichend schnelle Ausbau von Photovoltaik (PV) und Wind­kraft in Deutschland. Sch{\"a}tzungsweise kann der Elektrizit{\"a}tsbedarf im Jahr 2030 z.B. durch den Ausbau auf ca. 350 GW PV und ca. 150 GW Windkraft nahe­zu voll­st{\"a}ndig regenerativ gedeckt werden. Damit ließe sich eine zum großen Teil elek­tri­fizierte Mobilit{\"a}t und W{\"a}rmeversorgung betreiben und ein Teil des ben{\"o}­tig­ten "gr{\"u}­nen" Wasserstoffs in Deutschland bereitstellen. Hierf{\"u}r ist ein j{\"a}hr­licher Zu­bau von durchschnittlich ca. 30 GW PV und ca. 9 GW Windkraft n{\"o}tig. Dies ist ca. sechs- (PV) bzw. dreimal (Wind) so hoch wie bisher vorgesehen und verlangt eine ge­sell­schaft­liche Kraftanstrengung. Ein weiter verz{\"o}gerter Ausbau m{\"u}sste mit noch deut­lich gr{\"o}ßeren gesellschaftlichen Anstrengungen f{\"u}r drastische Energieeinspa­run­gen oder Importe erneuerbarer Energie ausgeglichen werden. Insgesamt k{\"o}nnte dies noch deutlich schwieriger zu realisieren sein, als ein ambitionierter Ausbau. Da der Auf­bau der Kapazit{\"a}ten mehrere Jahre erfordert, ist es m{\"o}glich nachzusteuern, z. B. wenn erkennbar wird, dass sich ein ausreichend großer globaler Markt f{\"u}r Importe ent­wi­ckelt. Bis dahin ist es aus Verantwortung gegen­{\"u}ber der Zukunft und im Sinne des Pariser Vertrages empfehlenswert, die hier genannten Ausbauziele zu verfol­gen. Gr{\"u}ner, also aus erneuerbaren Energien hergestellter Wasserstoff und daraus abge­lei­tete Syntheseprodukte sind f{\"u}r die Dekarbonisierung von Industrieprozessen, den Flug- und Schiffsverkehr sowie f{\"u}r die Absicherung der Energieversorgung bei Dun­kel­flauten n{\"o}tig. Ohne die genannten Ausbauziele f{\"u}r Wind und Solar noch drastisch weiter zu erh{\"o}hen, stehen diese Produkte f{\"u}r Straßenverkehr und W{\"a}rmeversor­gung jedoch nicht in ausreichenden Mengen zur Verf{\"u}gung. Techniken zum Aus­gleich zwischen Elektrizit{\"a}tsangebot und -nachfrage sind verf{\"u}gbar und sollten recht­zeitig auf- bzw. ausgebaut werden. Hierzu geh{\"o}ren: Stromaustausch mit den Nach­barl{\"a}ndern, Flexibilisierung des Verbrauchs und Energiespeicherung. F{\"u}r deren Inte­gration sowie den Ausbau der Netze sollten z{\"u}gig verbesserte rechtliche Rah­men­bedingungen geschaffen werden. Die Kosten eines klimavertr{\"a}glichen Energiesystems sind mittel- bis langfristig nicht h{\"o}­her als im derzeitigen System. Gleichzeitig entstehen Arbeitspl{\"a}tze und Export­chan­cen durch Aufbau, Betrieb und Wartung einer regenerativen Energieversorgung in Deutschland und die energetische Geb{\"a}udesanierung. Die politischen Rahmenbe­din­gungen entscheiden, ob eine klimavertr{\"a}gliche Energieversorgung Deutschlands ge­lingt.}, language = {de} } @inproceedings{Roesel, author = {R{\"o}sel, Birgit}, title = {A concept of a mainly digitalized course on control theory including problembased practical units and digital supported exams}, series = {HEAd'20: Sixth International Conference on Higher Education Advances, June 2 - June 5 2020, Valencia (Spain)}, booktitle = {HEAd'20: Sixth International Conference on Higher Education Advances, June 2 - June 5 2020, Valencia (Spain)}, doi = {10.4995/HEAd20.2020.11112}, abstract = {This paper decribes the concept of a course on control theory as a minor subject in the department of electrical engineering at the OTH Regensburg. The basis for a new concept is the idea of contructive alignment. The whole teaching module is devided in two blocks. The first block contains the teaching of the knowledge about control theory with an integrated approach for lectures, exercises and practical sessions. In the second block the students attent a practical work package to have the possibility to applicate and deepen their knowledge. To foster active participation the students are asked to document and reflect their work with the course context in an electronic portfolio. The exam of this module consists of three parts with respect to the different competencies obtained during the module. This concept develops not only the knowledge on control theory but personal and social competencies which are of growing interest. The aim of the paper is to present the idea of the concept. Following papers will illustrate the development process and the results obtained later on.}, language = {en} } @inproceedings{GoetzRauchBrueckl, author = {Goetz, Rebecca and Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Techno-economic analysis of reactive power sources}, series = {NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: Hamburg, 13.-14. September 2021}, booktitle = {NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: Hamburg, 13.-14. September 2021}, editor = {Schulz, Detlef}, publisher = {VDE-Verlag}, isbn = {978-3-8007-5651-3}, pages = {286 -- 291}, abstract = {This paper presents different options to provide reactive power in electricity grid systems. Since conventional power plants are being phased out and the reactive power demand tends to increase, alternative technologies are needed to cover it. reactive power sources are being defined and specified in this submission. A technical evaluation and an economic analysis of selected reactive power sources are carried out, based on interviews with manufacturers and operators. As well a multifactorial techno-economic comparison of the evaluated reactive power sources is presented. The technical analysis addresses reactive power control-ranges, stochastic parameters, lifespans, electrical losses and dynamics of re-active power sources. It states that power electronics allow faster setpoint changes than mechanical technologies can achieve, but at the same time this is associated with the highest electrical losses of the reactive power sources considered here. Considering the economic analysis, relative investment costs per reactive power of conventional compensation systems turn out to be the most cost-efficient. With regard to the multifactorial techno-economic comparison, it is im-portant not only to standardize on reactive power that can be provided, but also to include the additional system-relevant properties of technologies in the evaluation as well as the costs in operation.}, language = {en} } @inproceedings{RauchBrueckl, author = {Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Konzeptionierung netzplanerischer Prozessans{\"a}tze zur Ermittlung von Blindleistungskapazit{\"a}ten zum Ausgleich des Blindleistungsbedarfs in einer Netzregion}, series = {Tagungsband Tagung Zuk{\"u}nftige Stromnetze 26./27. Januar 2022 (online)}, booktitle = {Tagungsband Tagung Zuk{\"u}nftige Stromnetze 26./27. Januar 2022 (online)}, publisher = {Conexio-PSE GmbH}, address = {Pforzheim}, isbn = {978-3-948176-16-7}, doi = {10.35096/othr/pub-5866}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-58665}, pages = {117 -- 126}, abstract = {Um einen sicheren und zuverl{\"a}ssigen Stromnetzbetrieb zu gew{\"a}hrleisten, muss die Spannung im Grundfall als auch bei ungeplanten Ausf{\"a}llen in definierten Bereichen gehalten werden. Im {\"U}bertragungsnetz wird hierf{\"u}r bisher Blindleistung haupts{\"a}chlich aus Blindleistungskompensationsanlagen und konventionellen Großkraftwerken eingesetzt. Zuk{\"u}nftig wird nach \S12h EnWG eine marktgest{\"u}tzte Beschaffung dieser Dienstleistung zur Spannungsregelung vorgeschrieben. Zugleich ver{\"a}ndert sich der Blindleistungsbedarf der Netzbetriebsmittel durch die Integration erneuerbarer Energieanlagen und der Elektromobilit{\"a}t sowie durch den Netzausbau bei {\"U}bertragungs- und Verteilungsnetzbetreibern. Es bedarf somit angepasster Netzbetriebs- und Netzplanungskonzepte f{\"u}r ein technisch effizientes und wirtschaftlich g{\"u}nstiges Blindleistungsmanagement. Dieser Beitrag besch{\"a}ftigt sich damit, Prozessans{\"a}tze und Methodiken f{\"u}r ebendieses in der Netzplanung aufzuzeigen, um erforderliche Blindleistungskapazit{\"a}ten unter minimalen Gesamtkostenaufwand und unter Ber{\"u}cksichtigung einer effizienten Blindleistungsbedarfsdeckung zu bestimmen. Dabei liegt der Fokus verst{\"a}rkt in der Bedarfsanalyse.}, language = {de} } @inproceedings{SchweibererRauchBrueckl, author = {Schweiberer, Philipp and Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Entwicklung eines Regelkonzeptes f{\"u}r einen optimierten Blindleistungsabruf auf Basis von Blindleistungspotentialanalysen bei Industriebetrieben im Mittelspannungsnetz}, series = {Tagungsband Tagung Zuk{\"u}nftige Stromnetze 26./27. Januar 2022 (online)}, booktitle = {Tagungsband Tagung Zuk{\"u}nftige Stromnetze 26./27. Januar 2022 (online)}, publisher = {Conexio-PSE GmbH}, address = {Pforzheim}, isbn = {978-3-948176-16-7}, doi = {10.35096/othr/pub-5870}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-58704}, pages = {224 -- 233}, abstract = {Im Zuge der Energiewende ergibt sich ein Wandel in der Struktur des Elektrizit{\"a}tsversorgungsnetzes. Die Verschiebung der Erzeugungsleistung von konventionellen Großkraftwerken in h{\"o}heren Netzebenen hin zu dezentralen erneuerbaren Energieanlagen in niedrigeren Netzebenen resultiert sowohl in bidirektionalen Lastfl{\"u}ssen als auch in schwankenden Einspeisecharakteristiken. Des Weiteren folgen durch den Wegfall von Großkraftwerken als Blindleistungsquellen Leistungsdefizite in der {\"U}bertragungsnetzebene, die kompensiert werden m{\"u}ssen. Daraus resultieren Herausforderungen an einen sicheren und zuverl{\"a}ssigen Betrieb der Verteil- und {\"U}bertragungsnetze. Neue Konzepte m{\"u}ssen f{\"u}r die Erbringung von Blindleistung entwickelt werden, es soll mehr Blindleistung aus dem Verteilungsnetz zur Verf{\"u}gung gestellt werden, um die Systemstabilit{\"a}t zu wahren. Im Rahmen des Projektes Q-Integral wird das Thema „Blindleistung" (Q) ganzheitlich untersucht. Es werden dazu verschiedene Erbringungsoptionen f{\"u}r Blindleistung hinsichtlich technischer und wirtschaftlicher Potentiale untersucht, die in ein funktionales und effizientes Blindleistungsmanagement eingebracht werden. Die Untersuchungsans{\"a}tze daf{\"u}r sind sowohl spannungsebenen-{\"u}bergreifend als auch netzbetreiber-{\"u}bergreifend. Ein Ansatzpunkt des Projektes ist die Betrachtung der Blindleistungsbereitstellung von Industriebetrieben. Dazu wird das Potential von Betrieben, die an das Verteilnetz angeschlossen sind und Blindleistung durch Kompensations- oder Erzeugungsanlagen bereitstellen k{\"o}nnen, untersucht. Ziel ist es, das gesicherte und maximale induktive sowie kapazitive Potential zu bestimmen. Das gesicherte kapazitive Potential kann genutzt werden, um Aussagen dar{\"u}ber zu treffen, wie stark dem Spannungsfall im vorgelagerten Netz zu Starklastzeiten entgegengewirkt werden kann. Anhand des gesicherten induktiven Potentials kann ein Spannungsanstieg w{\"a}hrend Schwachlastzeiten ausgeglichen werden kann. In diesem Beitrag werden Ergebnisse aus dem Projekt Q-Integral vorgestellt. Dazu werden zuerst die Berechnungsgrundlagen der induktiven und kapazitiven Blindleistungspotentiale aufgezeigt und die Ergebnisse der Berechnungen vorgestellt. Die gewonnen Ergebnisse entstammen aus Messungen an einem Industriebetrieb mit Blindleistungskompensationsanlagen (BKA), den entsprechenden Reglern der Anlagen und einer installierten Kompensationsleistung von 1600 kvar. Sowohl die Lastg{\"a}nge als auch das Schaltverhalten der einzelnen Kompensationsanlagen liegen den Berechnungen zugrunde. Um den Austausch der Blindleistung an der {\"U}bergabestelle des Betriebs zum Mittelspannungsnetz netzdienlich einzustellen, bedarf es eines geeigneten Regelkonzepts, das neben den BKAs auch weitere Q-Quellen ber{\"u}cksichtigt. Deshalb wird abschließend ein Regelkonzept vorgestellt, das den technisch-optimierten Blindleistungsabruf unter Ber{\"u}cksichtigung mehrerer Blindleistungsquellen behandelt.}, language = {de} } @inproceedings{RauchBrueckl, author = {Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Analysis of the correlation behavior between local available information to the overall reactive power of a medium-voltage grid group}, series = {Applied Research Conference - ARC 2017, 7 July 2017 M{\"u}nchen}, booktitle = {Applied Research Conference - ARC 2017, 7 July 2017 M{\"u}nchen}, address = {M{\"u}nchen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-58712}, pages = {224 -- 230}, abstract = {The initiated energy transition leads to extensive changes in the supply of energy. The increasing use of renewable energy causes a shift of the produced power from centralized conventional power plants to decentralized energy plants. Because of this redistribution and the related change of load-flows, new challenges and problems for distribution system operators appear. This includes the integration of new loads and plants into the existing power grid and the guarantee of a high supply security and quality. It also includes strengthened requirements for the use and provision of reactive power. The project "SyNErgie" ("Systemoptimierendes Netz- und Energiemanagement f{\"u}r Verteilungsnetze der Zukunft") deals with the development of a new reactive power management, which gets embedded in grid planning and controlling processes. One focus of the project is on the integration of decentralized energy plants (DEPs) to the reactive power management. The aim is to develop a decentralized and self-sufficient reactive power control system, which only works with local available information (measures). Therefore is no necessity of a complex communication system to the grid control center. Self-controlled Q-controller in the DEPs get characteristic curves and control the reactive power sources with local measurements (e.g. current, voltage, effective power). This new reactive power control management aims for the reactive power compensation in order to increase the integration capacity of loads and plants in a grid [2]. In order to generate characteristic curves for DEPs, it is necessary to analyze the correlation behavior between the local available measurements at the DEPs and the overall-Q-behavior of the grid group at the transformer. In that regard, influencing quantities should be considered. The aim is to involve und evaluate all relevant influencing quantities in order to determine energy plants and certain operating points, in which the correlation behavior and the prediction for the overall-Q-behavior are sufficient. The next step is to develop a model that fits these correlation behaviors and generate characteristic curves. One method to generate characteristic curves for the Q-controllers is regression analysis. The developed Q-control-system with the characteristic curves will be tested, evaluated and optimized in a following field test in cooperation with distribution system operators.}, language = {de} } @article{MalzKrenkelSteffens, author = {Malz, Sebastian and Krenkel, Walter and Steffens, Oliver}, title = {Infrared Reflective Wall Paint in Buildings: Energy Saving Potentials and Thermal Comfort}, series = {Energy and Buildings}, volume = {224}, journal = {Energy and Buildings}, number = {October}, publisher = {Elsevier}, issn = {0378-7788}, doi = {10.1016/j.enbuild.2020.110212}, abstract = {The reduction of the energy demand of existing buildings is the main objective of building refurbishment. Managing the heat radiation properties of the wall construction is a possible way to develop highly effective and resource efficient insulation materials and concepts. The application of infrared reflective wall paints and coatings has been studied since the latter half of the 20th century. A brief review of the literature gives an account of the current research status. One has to realise that the conclusions are not uniformly consistent but depend strongly on the specific boundary conditions and investigated parameters. The study presented here discusses the usage of infrared reflective wall paint in conjunction with heat insulation for historic brick masonry. The possible energy savings are linked to the resulting thermal comfort. We identify critical parameters that must be taken into account when using infrared reflective wall paint and derive recommended design rules for the refurbishment of such building types. The findings prove that infrared reflective wall paint can decrease heat losses by 18\% and up to 22\% if comfort conditions are considered. Increasing energy savings can also cause the negative effect of high radiative asymmetry. Thus, each configuration must be observed in detail.}, language = {en} } @techreport{SternerSchummRanketal., author = {Sterner, Michael and Schumm, Leon and Rank, Daniel and Hofrichter, Andreas}, title = {Intelligente Netzpuffer : Abschlussbericht (24.01.2021)}, language = {de} } @article{SchulzSchwarz, author = {Schulz, Carsten and Schwarz, Colin}, title = {Drivetrain fatigue strength characteristics of model-predictive control for wind turbines}, series = {Wind Energy}, volume = {23}, journal = {Wind Energy}, number = {12}, publisher = {Wiley}, doi = {10.1002/we.2520}, pages = {2137 -- 2149}, abstract = {Wind turbines play a crucial role in the revolution towards renewable resources. They need to be economically competitive to be sustainable. This still requires to lower the cost of energy (COE). To this end, nonlinear model predictive control (NMPC) is used within this paper. As known from literature, NMPC significantly improves the energy extracting performance as well as the mitigation of tower loads of wind turbines. As it is shown in this paper, the drivetrain fatigue strength drops disproportionally in parallel, which either increases the demands on the turbine design or decreases the lifetime of drivetrain components. Without additional boundary conditions to the underlying optimal control problems (OCPs), the application of energy-maximizing NMPC might so even raise the COE. Only penalizing axial torque oscillations by quadratic terms decreases energy-extracting performance below the level of classical wind turbine controllers. This makes more sophisticated conditions necessary. In this paper, the increase of the drivetrain damage by NMPC is analyzed, and appropriate boundary conditions are derived, to balance the two contradicting objectives of energy maximization and drivetrain load mitigation. An NMPC approach based on indirect methods is used, to obtain a solution of the OCPs very efficiently. It applies the Hamilton equations and Pontryagin's maximum principle. Its accuracy and efficiency to solve OCPs was presented over the last decades.}, language = {en} } @article{HaumerKralVukovicetal., author = {Haumer, Anton and Kral, Christian and Vukovic, Vladimir and David, Alexander and Hettfleisch, Christian and Huzsvar, Attila}, title = {A Parametrization Scheme for High Performance Thermal Models of Electric Machines using Modelica}, series = {IFAC Proceedings Volumes}, volume = {45}, journal = {IFAC Proceedings Volumes}, number = {2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1474-6670}, doi = {10.3182/20120215-3-AT-3016.00187}, pages = {1058 -- 1062}, abstract = {Thermal models offer great advantages for enhancement of design, protection and control of electric machines. Detailed thermal models take a great number of time constants into account and provide accurate prediction of the temperatures. However, to parameterize such models detailed geometric data are needed. Whenever such detailed information is not available, or the performance of the detailed models is not satisfying, simplified thermal models as described in this paper are advantageous. The calculation of parameters is described in detail, in order to achieve best accordance with temperatures obtained from measurements or from simulations with detailed thermal models. Thermal resistances are calculated from end temperatures of a test run with constant load (and known losses). Thermal capacitances are obtained using optimization to minimize deviation of simulated and measured temperatures during the whole test run. The thermal model of an asynchronous induction machine with squirrel cage is coupled with an electrical model of the drive. For validation, simulation results of an optimally parameterized simplified model are compared with temperatures obtained by simulation of a detailed thermal model, which in turn has been validated against measurement results, both for continuous duty S1 and intermittent duty S6 (6 minutes no-load followed by 4 minutes of 140\% nominal load). The deviations are not more than 4 K which is quite satisfying.}, language = {en} } @article{KralHaumerHaigisetal., author = {Kral, Christian and Haumer, Anton and Haigis, Matthias and Lang, Hermann and Kapeller, Hansj{\"o}rg}, title = {Comparison of a CFD Analysis and a Thermal Equivalent Circuit Model of a TEFC Induction Machine With Measurements}, series = {IEEE Transactions on Energy Conversion}, volume = {24}, journal = {IEEE Transactions on Energy Conversion}, number = {4}, publisher = {IEEE}, issn = {0885-8969}, doi = {10.1109/TEC.2009.2025428}, pages = {809 -- 818}, abstract = {For a totally enclosed fan-cooled induction machine, two methods of numerical analysis are compared with measurements. The first numerical method is based on computational fluid dynamics (CFDs) and the second one uses a thermal equivalent circuit (TEC). For the analysis based on CFD, a 3-D induction machine including housing is modeled. The numeric solution of the flow equations is determined for stationary temperature distributions. For the TEC, a discretized one-and-a-half-dimensional model of the induction machine is considered. With the TEC model, stationary and transient operating conditions can be simulated. Measurement results are determined by iron-copper-nickel sensors embedded in the stator winding and the housing, as well as by an IR sensor for measuring the rotor temperature. With these measurement signals, stationary and transient operating conditions can be analyzed. For stationary operating conditions, additionally, the housing temperatures are determined by an IR camera. The investigated simulation and measurement methods reveal different local and global temperatures, and thus, only certain aspects and characteristics of the obtained temperatures can be compared. Nevertheless, certain conclusions can be drawn from comparing these aspects considering the actual restrictions of each of the applied methods.}, language = {en} } @article{KralKapellerGraggeretal., author = {Kral, Christian and Kapeller, Hansj{\"o}rg and Gragger, Johannes V. and Haumer, Anton and Kubicek, Bernhard}, title = {Phenomenon Rotor Fault-Multiple Electrical Rotor Asymmetries in Induction Machines}, series = {IEEE Transactions on Power Electronics}, volume = {25}, journal = {IEEE Transactions on Power Electronics}, number = {5}, publisher = {IEEE}, issn = {0885-8993}, doi = {10.1109/TPEL.2009.2037502}, pages = {1124 -- 1134}, abstract = {In the literature, the effects caused by a single or several adjacently broken rotor bars, or a broken end ring are thoroughly investigated. The phenomenon of various nonadjacently broken rotor bars has not been studied so far in detail. Since nonadjacently broken rotor bars may give rise to fault signatures, which are not directly related with the fault extent, it is important to understand the nature of multiple electrical rotor asymmetries in induction machines. The purpose of this paper is thus to investigate several combinations of electrical rotor asymmetries, to systematically elaborate the phenomena related to the broken bars and end rings. In this paper, a sophisticated simulation model and measurement results are used to analyze the phenomenon rotor fault.}, language = {en} } @inproceedings{EbnerHaumerSimicetal., author = {Ebner, Arno and Haumer, Anton and Simic, Dragan and Pirker, Franz}, title = {Interacting Modelica using a Named Pipe for Hardware-in-the-loop Simulation}, series = {Modelica 2006, Conference proceedings / 5th International Modelica Conference : September 4 - 5, 2006, Vienna, Austria}, booktitle = {Modelica 2006, Conference proceedings / 5th International Modelica Conference : September 4 - 5, 2006, Vienna, Austria}, pages = {261 -- 266}, abstract = {The paper presents a concept and an implementation of Modelica simulation interaction using the operating system inter-process communication method of the Named Pipe. The main aim of this presented work is to implement a hardware-in-the-loop simulation (HILS) environment based on Dymola which runs on a normal Microsoft Windows Personal Com-puter. An energy storage test bench is connected by an ana-logue and digital data input/output card with the Dymola simulation computer. With this proposed system, particularly long-time simulations with sample rates up to 30 Hz can be executed very cost effective. Typical applications are simulations of drive cycles to test energy storage systems in electrified vehicles such as batteries or fuel cells. Other application ex-amples are the verification of battery models, thermal management models or battery management sys-tem (BMS) models. In this paper all methods used for implementation are described in detail. Especially the concept of inter-process communication and the concept for real-time and simulation time synchronization is discused. An application example which uses the provided concept is also shown at in this paper. In this example a longitudinal simulation of a vehicle is pre-sented. The startup phase of the internal combusting engine model and a short drive cycle in combination with a connected real battery is shown.}, language = {en} } @inproceedings{BaeumlHaumerKapelleretal., author = {B{\"a}uml, T. and Haumer, Anton and Kapeller, H. and Starzinger, J. and Farzi, P.}, title = {Impact of inverter pulse inhibition on the high-voltage supply system of an electric vehicle — A simulative approach}, series = {2011 IEEE Vehicle Power and Propulsion Conference (VPPC 2011) : Powering sustainable transportation ; Chicago, Illinois, USA, 06. - 09.09.2011}, booktitle = {2011 IEEE Vehicle Power and Propulsion Conference (VPPC 2011) : Powering sustainable transportation ; Chicago, Illinois, USA, 06. - 09.09.2011}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-61284-248-6}, doi = {10.1109/VPPC.2011.6043159}, pages = {1 -- 5}, abstract = {This paper deals with a simulative approach for investigating the impact of inverter pulse inhibition during field weakening operation of permanent magnet synchronous machines and asynchronous induction machines. The modelling and simulation language Modelica is used to design models for the vehicle, the electric machine and the inverter in different abstraction levels. It is shown that when using a permanent magnet synchronous machine, a sudden breakdown of the field weakening current causes induction of high voltages in the stator windings. Hence, the electric system of the vehicle has to be protected against the resulting high currents. Furthermore precautions have to be taken to avoid dangerous driving conditions because of high braking torques in an inverter fault operation mode. In the case of the asynchronous induction machine an inverter pulse inhibition poses no big problem, neither for the electric system of the vehicle, nor the driver.}, language = {en} } @inproceedings{BogomolovKralHaumeretal., author = {Bogomolov, Maxim and Kral, Christian and Haumer, Anton and Lomonova, Elena}, title = {Modeling of permanent magnet synchronous machine with fractional slot windings}, series = {Proceedings IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society ; Ecole de Technologie Superieure de Montreal, Universite du Quebec Montreal, Canada 25 - 28 October, 2012}, booktitle = {Proceedings IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society ; Ecole de Technologie Superieure de Montreal, Universite du Quebec Montreal, Canada 25 - 28 October, 2012}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-2421-2}, issn = {1553-572X}, doi = {10.1109/IECON.2012.6388912}, pages = {1894 -- 1899}, abstract = {This paper focuses on simulation of permanent magnet synchronous machine (PMSM) with fractional-slot windings (FSW) in Modelica. Modeling of the electrical machines with object-oriented approach is shortly described, and a new Modelica library for simulation of electrical machines is introduced. The results of simulation of PMSMs with fractional slot windings are presented and explained. Special attention is paid to the higher harmonics and subharmonics produced by the winding and their influence on machine operation.}, language = {en} } @inproceedings{HongHyunKangetal., author = {Hong, Jongman and Hyun, Doosoo and Kang, Tae-june and Lee, Sang Bin and Kral, Christian and Haumer, Anton}, title = {Detection and classification of rotor demagnetization and eccentricity faults for PM synchronous motors}, series = {2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011) : Energy conversion innovation for a clean energy future ; Phoenix, Arizona, USA, 17.-22.09.2011}, booktitle = {2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011) : Energy conversion innovation for a clean energy future ; Phoenix, Arizona, USA, 17.-22.09.2011}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4577-0542-7}, issn = {2329-3721}, doi = {10.1109/ECCE.2011.6064103}, pages = {2512 -- 2519}, abstract = {Condition monitoring of rotor problems such as demagnetization and eccentricity in permanent magnet synchronous motors (PMSM) is essential for guaranteeing high motor performance, efficiency, and reliability. However, there are many limitations to the off-line and on-line methods currently used for PMSM rotor quality assessment. In this paper, an inverter-embedded technique for automated detection and classification of PMSM rotor faults is proposed as an alternative. The main concept is to use the inverter to perform a test whenever the motor is stopped, to detect rotor faults independent of operating conditions or load torque oscillations, which is not possible with motor current signature analysis (MCSA). The d-axis is excited with a dc+ac signal, and the variation in the inductance pattern due to the change in the degree of magnetic saturation caused by demagnetization or eccentricity is observed for fault detection. An experimental study on a 7.5kW PMSM verifies that demagnetization and eccentricity can be detected and classified independent of the load with high sensitivity.}, language = {en} } @inproceedings{HongLeeKraletal., author = {Hong, Jongman and Lee, Sang Bin and Kral, Christian and Haumer, Anton}, title = {Detection of airgap eccentricity for permanent magnet synchronous motors based on the d-axis inductance}, series = {8th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics \& Drives (SDEMPED), 2011 // 05. - 08.09.2011, Bologna, Italy}, booktitle = {8th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics \& Drives (SDEMPED), 2011 // 05. - 08.09.2011, Bologna, Italy}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4244-9301-2}, doi = {10.1109/DEMPED.2011.6063651}, pages = {378 -- 384}, abstract = {The majority of the work performed for detecting eccentricity faults for permanent magnet synchronous motors (PMSM) focus on motor current signature analysis (MCSA), as it provides continuous on-line monitoring with existing current sensors. However, MCSA cannot be applied under nonstationary conditions and cannot distinguish faults with load torque oscillations, which are limitations for many PMSM drive applications. In this paper, it is shown that the d-axis inductance, L d , decreases with increase in the severity of eccentricity due to the change in the degree of magnetic saturation, and it is proposed as a new fault indicator. The inverter can be used to perform a standstill test automatically whenever the motor is stopped, to measure L d for eccentricity testing independent of load variations or oscillations, which is not possible with MCSA. An FE and experimental study on a 10hp PMSM verifies that eccentricity can be detected independent of the load with high sensitivity and reliability.}, language = {en} } @inproceedings{HaumerKral, author = {Haumer, Anton and Kral, Christian}, title = {Modeling a Mains connected PWM Converter with Voltage-Oriented Control}, series = {Proceedings of the 8th International Modelica Conference, Technical Univeristy, Dresden, Germany, 20.-22.03.2011}, booktitle = {Proceedings of the 8th International Modelica Conference, Technical Univeristy, Dresden, Germany, 20.-22.03.2011}, publisher = {Link{\"o}ping University Electronic Press}, doi = {10.3384/ecp11063388}, pages = {388 -- 397}, abstract = {The majority of industrial controlled induction machine drives are connected to the mains via a diode bridge. However; if reduction of harmonic currents and / or regenerative operation is desired; replacing the diode bridge by an active front-end (AFE) is required. This paper describes two models of an AFE: a power balance model disregarding switching effects; and an ideal switching model of a pulse width modulation (PWM) converter. Both models are controlled utilizing space phasors in a voltage oriented reference frame. Voltage oriented control (VOC) of the mains converter can be compared with field oriented control (FOC) of a machine converter. Design and parametrization of the main parts—synchronization with mains voltage; current controller and DC voltage controller—are described in detail. Additionally; simulation results proving the implementation and demonstrating possible investigations as well as an outlook on further enhancements are presented.}, language = {en} } @inproceedings{JungreuthmayerBaumlWinteretal., author = {Jungreuthmayer, C. and Bauml, T. and Winter, O. and Ganchev, M. and Kapeller, H. and Haumer, Anton and Kral, Christian}, title = {Heat and fluid flow analysis of an internal permanent magnet synchronous machine by means of computational fluid dynamics}, series = {2011 IEEE International Electric Machines \& Drives Conference (IEMDC 2011) ; Niagara Falls, Ontario, Canada, 15 - 18 May 2011}, booktitle = {2011 IEEE International Electric Machines \& Drives Conference (IEMDC 2011) ; Niagara Falls, Ontario, Canada, 15 - 18 May 2011}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4577-0060-6}, doi = {10.1109/IEMDC.2011.5994651}, pages = {515 -- 520}, abstract = {This paper presents a comprehensive computational fluid (CFD) model of a radial flux permanent magnet synchronous machine with interior magnets. In the CFD model the water jacket cooling and a simplified model of the topology of the distributed stator winding are considered. The heat sources of the CFD model are determined from a finite element analysis of the machine. The numerically determined temperature distributions of the machine are compared with measurement results from sensors located both in the stator and rotor. The particular focus of this paper is the analysis of the temperatures and the heat flow in the air gap and from the stator winding head and the rotor to the inner air.}, language = {en} } @inproceedings{HaumerKral, author = {Haumer, Anton and Kral, Christian}, title = {Motor Management of Permanent Magnet Synchronous Machines}, series = {Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany}, booktitle = {Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany}, editor = {Otter, Martin and Zimmer, Dirk}, publisher = {Link{\"o}ping University Electronic Press}, isbn = {978-91-7519-826-2}, issn = {1650-3686}, doi = {10.3384/ecp12076159}, pages = {159 -- 166}, abstract = {Two state-of-the-art machine designs are mainly used in recent electric and hybrid electric vehicles: asynchronous induction machines with squirrel cage which are robust but need a current component to excite the magnetic field; and permanent magnet synchronous machines which rely on somehow more sensible parts but the magnets are able to excite a magnetic field without current. However; if speed gets high enough to reach the field weakening range; for both machine the field oriented control has to prescribe a field current sufficient to reduce the field not to exceed the voltage limits of the stator circuit. Especially for the permanent magnet synchronous machine this paper investigates whether it is possible to determine an optimal field current for every operation point to minimize either total current consumption or losses.}, language = {en} } @incollection{KapellerHaumerKraletal., author = {Kapeller, Hansj{\"o}rg and Haumer, Anton and Kral, Christian and Grabner, Christian}, title = {Different Designs of Large Chipper Drives}, series = {Electronic Engineering and Computing Technology}, booktitle = {Electronic Engineering and Computing Technology}, editor = {Ao, Sio-Iong and Gelman, Len}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-90-481-8775-1}, doi = {10.1007/978-90-481-8776-8_9}, pages = {93 -- 104}, abstract = {This paper presents two simulation models for two variants of a large chipper drive used in a paper mill. If a slip ring induction motor is used, the impact of a rotor circuit rheostat with respect to starting behavior and heavy duty load impulses can be examined. Furthermore a speed controlled squirrel cage induction machine will be investigated. The modeling language for both drives is Modelica. The simulation results for both drives are compared and discussed.}, language = {en} } @inproceedings{KralHaumerBogomolovetal., author = {Kral, Christian and Haumer, Anton and Bogomolov, Maxim and Lomonova, Elena}, title = {Harmonic wave model of a permanent magnet synchronous machine for modeling partial demagnetization under short circuit conditions}, series = {2012 XXth International Conference on Electrical Machines (ICEM 2012) ; Marseille, France, 2 - 5 September 2012}, booktitle = {2012 XXth International Conference on Electrical Machines (ICEM 2012) ; Marseille, France, 2 - 5 September 2012}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-0142-8}, doi = {10.1109/ICElMach.2012.6349880}, pages = {295 -- 301}, abstract = {This paper proposes a multi domain physical model of permanent magnet synchronous machines, considering electrical, magnetic, thermal and mechanical effects. For each component of the model, the main wave as well as lower and higher harmonic wave components of the magnetic flux and the magnetic potential difference may be considered. The permanent magnets are modeled as discrete azimuthal segments in order to consider possible partial demagnetization effects. For each magnet segment a linearized temperature dependent B-H curve is considered. The main advantage of the presented model is that time transient operational behavior of a permanent magnet synchronous machine can be considered under various electrical, magnetic, thermal and mechanical conditions. The electromagnetic condition of surface magnet machine is compared with finite element analysis.}, language = {en} } @inproceedings{KralHaumerLee, author = {Kral, Christian and Haumer, Anton and Lee, Sang Bin}, title = {Robust thermal model for the estimation of rotor cage and stator winding temperatures of induction machines}, series = {2012 XXth International Conference on Electrical Machines ; Marseille, France, 02.- 05.09.2012}, booktitle = {2012 XXth International Conference on Electrical Machines ; Marseille, France, 02.- 05.09.2012}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-0142-8}, doi = {10.1109/ICElMach.2012.6350127}, pages = {1810 -- 1816}, abstract = {In this paper a new model for the estimation of the stator winding and rotor cage temperatures of induction machines is presented. This model can be used in series applications of machines operated under dynamic load conditions where stator and rotor temperature shall be monitored. The proposed model relies on a simplified lumped element thermal equivalent circuit model where the stator core temperature serves as input quantity. The great advantage of this model is that it covers ambient and cooling conditions inherently. This leads to great simplicity and robustness. The parametrization and validation of the model through experimental data is presented. Advantages, drawbacks and possible implementations are discussed.}, language = {en} } @inproceedings{KralHaumerLee, author = {Kral, Christian and Haumer, Anton and Lee, Sang Bin}, title = {Innovative thermal model for the estimation of permanent magnet and stator winding temperatures}, series = {2012 IEEE Energy Conversion Congress and Exposition (ECCE 2012) ; Raleigh, NC, USA 15.09.-20.09.2012}, booktitle = {2012 IEEE Energy Conversion Congress and Exposition (ECCE 2012) ; Raleigh, NC, USA 15.09.-20.09.2012}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-0803-8}, issn = {2329-3721}, doi = {10.1109/ECCE.2012.6342386}, pages = {2704 -- 2711}, abstract = {In this paper an innovative thermal model for the determination of the temperatures of the permanent magnets and stator windings is presented. This model relies on one temperature sensor located in the stator core of the machine. The estimated stator winding and permanent magnet temperatures are determined by a simplified thermal lumped element network model with only two time constants. Due to the structure of the model and the measured stator core temperature the proposed thermal model is very robust. Distortion of the cooling circuit are inherently sensed such that the model can be used for the online prediction of temperatures. Experimental results based on an interior permanent magnet synchronous machine are presented to validate the presented model.}, language = {en} } @inproceedings{KralHaumer, author = {Kral, Christian and Haumer, Anton}, title = {The New FundamentalWave Library for Modeling Rotating Electrical Three Phase Machines}, series = {Proceedings of the 8th International Modelica Conference; March 20th-22nd; Technical Univeristy; Dresden; Germany}, booktitle = {Proceedings of the 8th International Modelica Conference; March 20th-22nd; Technical Univeristy; Dresden; Germany}, publisher = {University Electronic Press}, address = {Link{\"o}ping}, isbn = {978-91-7393-096-3}, issn = {1650-3686}, doi = {10.3384/ecp11063170}, pages = {170 -- 179}, abstract = {This paper introduces the new FundemantalWave library which is included in the Modelica Standard Library 3.2. The presented Modelica package provides models and components of rotating electrical three phase machines. The presented electrical machine models are fully compatible with the original Machines library of the electrical domain but rely on the concept of the magnetic potential and magnetic flux fundamental waves. In this article; the connector concept; the components and electric machine models of the FundemantalWave package will be explained. Additionally; the didactic advantages and the flexibility of the proposed package in with respect to considering more enhanced and sophisticated effects will be discussed.}, language = {en} } @incollection{KralHaumerGrabner, author = {Kral, Christian and Haumer, Anton and Grabner, Christian}, title = {Determination of Consistent Induction Motor Parameters}, series = {Electronic Engineering and Computing Technology}, volume = {60}, booktitle = {Electronic Engineering and Computing Technology}, editor = {Ao, Sio-Iong and Gelman, Len}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-90-481-8775-1}, doi = {10.1007/978-90-481-8776-8_7}, pages = {71 -- 80}, abstract = {From the rating plate data of an induction motor the nominal efficiency can be determined. Without detailed knowledge of equivalent circuit parameters, partial load behavior cannot be computed. Therefore, a combined calculation and estimation scheme is presented, where the consistent parameters of an equivalent circuit are elaborated, exactly matching the nominal operating point. From these parameters part load efficiencies can be determined.}, language = {en} } @incollection{KralHaumerGrabner, author = {Kral, Christian and Haumer, Anton and Grabner, Christian}, title = {Broken Rotor Bars in Squirrel Cage Induction Machines - Modeling and Simulation}, series = {Electronic Engineering and Computing Technology}, booktitle = {Electronic Engineering and Computing Technology}, editor = {Ao, Sio-Iong and Gelman, Len}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-90-481-8775-1}, doi = {10.1007/978-90-481-8776-8_8}, pages = {81 -- 91}, abstract = {This paper presents a physical model of a squirrel cage induction machine with rotor topology. The machine is modeled in Modelica, an object oriented multi physical modeling system. The presented machine model is used to investigate electrical rotor asymmetries in induction machines. For the case of a single broken rotor bar a simulation model is compared with measurement results.}, language = {en} } @incollection{KralHaumer, author = {Kral, Christian and Haumer, Anton}, title = {Object Oriented Modeling of Rotating Electrical Machines}, series = {Advances in Computer Science and Engineering}, booktitle = {Advances in Computer Science and Engineering}, editor = {Schmidt, Matthias}, publisher = {IntechOpen}, isbn = {978-953-307-173-2}, doi = {10.5772/15898}, pages = {135 -- 160}, language = {en} } @inproceedings{SippenauerBruecklHenneke, author = {Sippenauer, Thomas and Br{\"u}ckl, Oliver and Henneke, Markus}, title = {Verankerung von Flexibilit{\"a}t in der Netzplanung}, series = {Zuk{\"u}nftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021}, booktitle = {Zuk{\"u}nftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021}, publisher = {Conexio GmbH}, address = {Pforzheim}, isbn = {978-3-948176-12-9}, doi = {10.35096/othr/pub-5563}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-55632}, pages = {79 -- 92}, abstract = {Die Energiewende f{\"u}hrt zu einem steigenden Zubau erneuerbarer Energieerzeugungsanlagen im Verteilungsnetz. Ebenso ist mit einem verst{\"a}rkten Zuwachs der Elektromobilit{\"a}t zu rechnen, der zu einer weiteren Ausreizung der zul{\"a}ssigen Spannungsbereiche und Leitungsauslastungen beitragen kann. Um die Aufnahmef{\"a}higkeit des Verteilungsnetzes zu erh{\"o}hen, wurden in der Vergangenheit verschiedene L{\"o}sungen entwickelt und etabliert. Ein zus{\"a}tzlicher Baustein zur Behebung von Netzengp{\"a}ssen und Spannungsproblemen sind zeitliche Verlagerungen von Einspeisungen und Verbrauchslasten in der Mittelspannungsebene. Diese sogenannten Flexibilit{\"a}tsmaßnahmen sind derzeit noch nicht Stand der Technik. Um einen hohen Nutzen stiften zu k{\"o}nnen, indem sie zu einer effizienten Einsparung an Asset beitragen, m{\"u}ssen sie in der Netzplanung abbildbar gemacht werden. Dazu sind einerseits geeignete technische und zuverl{\"a}ssigkeitstheoretische Anforderungen an die Flexibilit{\"a}tsmaßnahmen herauszuarbeiten, um eine m{\"o}glichst hohe Gesamteffizienz bei Netz- und Anlagenbetreibern zu erzielen und andererseits ein Verfahren zu finden, mit dem Manipulationsm{\"o}glichkeiten (INC-DEC-Gaming) ausgeschlossen bzw. geringgehalten werden k{\"o}nnen.}, language = {de} } @inproceedings{SippenauerBrueckl, author = {Sippenauer, Thomas and Br{\"u}ckl, Oliver}, title = {Verankerung von Flexibilit{\"a}t in der Netzplanung}, series = {ScienceLab (begleitender Workshop zur Konferenz Zuk{\"u}nftige Stromnetze: 29.-30. Januar 2020, Berlin)}, booktitle = {ScienceLab (begleitender Workshop zur Konferenz Zuk{\"u}nftige Stromnetze: 29.-30. Januar 2020, Berlin)}, publisher = {Conexio GmbH}, address = {Pforzheim}, isbn = {978-3-948176-07-5}, doi = {10.35096/othr/pub-5559}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-55592}, pages = {77 -- 81}, abstract = {Im Rahmen des Projektes C/sells wurden mehrere Mittelspannungsnetze modelliert, um die aktuellen Spannungsverh{\"a}ltnisse und Leitungsauslastungen nachbilden zu k{\"o}nnen. Zudem wurden, angelehnt an den Netzentwicklungsplan, Szenarien f{\"u}r den zuk{\"u}nftigen PV-Zubau und die potenzielle Entwicklung der Elektromobilit{\"a}t entworfen. Auf Basis der Ergebnisse l{\"a}sst sich eine Netzanalyse hinsichtlich Spannungs- und Stromgrenzwert{\"u}berschreitungen sowie zu deren potenziellen Auftrittszeitpunkten und Auftrittsdauern durchf{\"u}hren. Parallel wurde anhand von Sensitivit{\"a}tsanalysen untersucht, welche Wirksamkeit Flexibilit{\"a}tseins{\"a}tze an den verschiedenen Netzknoten auf den Engpass haben. Dadurch kann bestimmt werden, wie effektiv die verf{\"u}gbaren, in der Regel {\"o}rtlich gebundenen Flexibilit{\"a}tsanbieter eingesetzt werden k{\"o}nnen. Da die Sensitivit{\"a}ten arbeitspunktabh{\"a}ngig sind, wurden verschiedene Zeitpunkte im Jahresverlauf berechnet und die jeweilige {\"A}nderungen der Wirksamkeit ausgewertet. Neben der H{\"o}he der Leistungsabweichung wurde die Flexibilit{\"a}tsanforderung auch anhand der Einsatzzeitpunkte und Einsatzdauer sowie anhand der H{\"a}ufigkeit der n{\"o}tigen Flexibilit{\"a}tseins{\"a}tze charakterisiert. Aus den gewonnenen Erkenntnissen soll abgeleitet werden, inwiefern sich der flexible Einsatz der Verbrauchsanlagen in der Netzplanung verankern l{\"a}sst. Besonders relevant ist deshalb, mit welcher Verl{\"a}sslichkeit die Flexibilit{\"a}t abgerufen werden kann. Eine sehr hohe Verl{\"a}sslichkeit l{\"a}sst sich je nach Flexibilit{\"a}tsanbieter m{\"o}glicherweise nicht oder nur zu sehr hohen Preisen gew{\"a}hrleisten. Die Eignung der Flexibilit{\"a}tseins{\"a}tze wird somit sowohl aus technischer als auch aus wirtschaftlicher Sicht bewertet. Da eine vollst{\"a}ndige Verl{\"a}sslichkeit ohnehin nicht sichergestellt werden kann (technische St{\"o}rungen einer Anlage, Wettereinfl{\"u}sse, etc.), werden auch Fallback-Strategien, z. B. Einspeisespitzenkappung, in die Analyse einbezogen.}, language = {de} } @inproceedings{SippenauerBrueckl, author = {Sippenauer, Thomas and Br{\"u}ckl, Oliver}, title = {Erschließung der Flexibilit{\"a}tspotenziale eines Trinkwasserversorgungssystems}, series = {ScienceLab (begleitender Workshop zur Konferenz „Zuk{\"u}nftige Stromnetze": 2020, Berlin)}, booktitle = {ScienceLab (begleitender Workshop zur Konferenz „Zuk{\"u}nftige Stromnetze": 2020, Berlin)}, publisher = {Conexio GmbH}, address = {Pforzheim}, isbn = {978-3-948176-07-5}, doi = {10.35096/othr/pub-5562}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-55629}, pages = {126 -- 130}, abstract = {In Zusammenarbeit mit den Kreiswerken Cham wurde an der OTH Regensburg das Trinkwasserversorgungsgebiet mit allen relevanten Pumpen und Hochbeh{\"a}ltern nachgebildet. Mithilfe des Modells kann die aktuelle, f{\"u}llstandgesteuerte Betriebsweise unter Einhaltung der Randbedingungen (Grenzwerte der Beh{\"a}lterf{\"u}llst{\"a}nde, elektrische Verschaltung der Pumpen) simuliert werden. Daraus l{\"a}sst sich auch das gesicherte, f{\"u}r die Netzplanung geeignete Flexibilit{\"a}tspotenzial anhand der Leistungsabweichung gegen{\"u}ber dem regul{\"a}ren Fahrplan, der Einsatzdauer, dem Einsatzzeitpunkt und der Pause zwischen den Flexibilit{\"a}tsabrufen charakterisieren. In einem Feldversuch wurde vordergr{\"u}ndig untersucht, inwiefern der Einsatz von Flexibilit{\"a}t in der Trinkwasserversorgung technisch umsetzbar ist.}, language = {de} } @article{BruecklHaslbeckPortneretal., author = {Br{\"u}ckl, Oliver and Haslbeck, Matthias and Portner, Olaf and Hinz, Gerhard}, title = {Kostenminimaler Netzanschluss einer 8-MW-PV-Anlage mithilfe regelbarer Ortsnetztransformatoren}, series = {Energiewirtschaftliche Tagesfragen}, volume = {64}, journal = {Energiewirtschaftliche Tagesfragen}, number = {6}, publisher = {Energiewirtschaft und Technik, Verl.-Ges.}, address = {Gr{\"a}felfing}, pages = {63 -- 65}, abstract = {Die steigende Anzahl der Erzeugungsanlagen (EZA) in den Verteilnetzen zwingt viele Verteilnetzbetreiber zum kostenintensiven Netzausbau. Dabei sind die EZA gem{\"a}ß EEG am technisch und wirtschaftlich g{\"u}nstigsten Verkn{\"u}pfungspunkt anzuschließen. Zur Bestimmung dieses Punktes ist ein Vergleich sinnvoller Netzanschlussvarianten durchzuf{\"u}hren. Regelbare Ortsnetztransformatoren (RONT) erweitern seit Kurzem die Netzanschlussm{\"o}glichkeiten, auch auf Mittelspannungsebene. Das Beispiel eines Anschlusses f{\"u}r eine 8-MW-PV-Anlage zeigt, dass der optimale Netzanschluss eine Kombination zwischen RONT, Spannungsblindleistungsregelung, Trennstellenverlagerung und Leitungsverst{\"a}rkung sein kann. In diesem Fall bemerkenswert ist, dass der RONT-Einsatz die Netzanschlusskosten um rd. 60 \% gegen{\"u}ber einer separaten Anbindung am Umspannwerk reduziert. Die Autoren beschreiben eingangs die Problematik hoher Netzausbaukosten beim Anschluss von Photovoltaik-Fl{\"a}chenanlagen. Das Vorgehen der durchgef{\"u}hrten Netzanalyse im konkreten Fall (Abb.: Grafische Darstellung des s{\"u}dlichen MS-Netzes der Stadtwerke Kehlheim mit angedeuteter Einspeiseleistung) und die 6 analysierten Netzanschlussvarianten werden beschrieben und diskutiert (Abb.: Gegen{\"u}berstellung der Investitionen der verschiedenen Netzausbauszenarien). Die oben genannte g{\"u}nstigste Anschlussvariante besteht aus folgender Kombination: Verlegung der vorhandenen Netztrennstelle zwischen zwei 20-kV-Str{\"a}nge; Verst{\"a}rkung einer bestehenden Freileitungsstrecke {\"u}ber 1 km; Einsatz von maximal 15RONT sowie Spannungsblindleistungsregelung durch die PV-Fl{\"a}chenanlage.}, language = {de} } @inproceedings{HaslbeckRauchBrueckletal., author = {Haslbeck, Matthias and Rauch, Johannes and Br{\"u}ckl, Oliver and B{\"a}smann, Rainer and G{\"u}nther, Andreas and Rietsche, Hansj{\"o}rg and Tempelmeier, Achim}, title = {Blindleistungsmanagement in Mittelspannungsnetzen}, series = {Zuk{\"u}nftige Stromnetze 2019, 30.-31.Jan.2019, Berlin}, booktitle = {Zuk{\"u}nftige Stromnetze 2019, 30.-31.Jan.2019, Berlin}, pages = {170 -- 182}, abstract = {Die Energiewende f{\"u}hrt zu neuen Herausforderungen f{\"u}r Verteilungsnetzbetreiber hinsichtlich der Erbringung von Systemdienstleistungen, der Integrationsf{\"a}higkeit weiterer Erzeugungsanlagen und Lasten sowie bei der Gew{\"a}hrleistung einer hohen Versorgungssicherheit. Die Deckung der steigenden Blindleistungsbedarfe seitens der Netzbetriebsmittel, Verbraucher und Erzeuger gewinnt durch den Wegfall der Großkraftwerke f{\"u}r Netzbetreiber zunehmend an Bedeutung.Das abgeschlossene und vom BMWi gef{\"o}rderte Projekt SyNErgie (Laufzeit von 03/2015 bis 05/2018) besch{\"a}ftigt sich mit der Entwicklung von Blindleistungsmanagementsystemen f{\"u}r Mittelspannungsnetze (MS-Netze). Ziel dabeiist es, das bisher ungenutzte, freie Blindleistungspotenzial betrieblicher Kompensationsanlagen und dezentraler Erzeugungsanlagen (allg.: Q-Quellen) zu nutzen, um die Blindleistungs{\"a}nderungsf{\"a}higkeit 1 eines Verteilungsnetzes zu erh{\"o}hen. Diese Ver{\"o}ffentlichung stellt ausgew{\"a}hlte Einzelergebnisse und Erfahrungen des Projektes vor, welche u. a. {\"u}ber zahlreiche Messungen inMS-Netzen bei Firmen mit Anschlusspunkt in der MS-Ebene, Netzsimulationen und mathematische Modelle abgeleitet wurden.}, language = {de} } @misc{HaslbeckBrueckl, author = {Haslbeck, Matthias and Br{\"u}ckl, Oliver}, title = {Liberalisierung von Systemdienstleistungen}, series = {Zuk{\"u}nftige Stromnetze f{\"u}r erneuerbare Energien}, journal = {Zuk{\"u}nftige Stromnetze f{\"u}r erneuerbare Energien}, publisher = {Ostbayerisches Technologie-Transfer-Institut (OTTI)}, address = {Regensburg}, isbn = {978-3-943891-34-8}, pages = {170 -- 175}, abstract = {Die Liberalisierung der Blindleistung und Schaffung von regionalen nicht ausschreibungspflichtigen Q-Beschaffungsprozessen erm{\"o}glicht vor allem k{\"u}nftig erhebliche Kostenreduktionspotenziale. Allerdings ist die Etablierung mit umfangreichen Eingriffen in den heutigen Normen- und Gesetzesrahmen verbunden. Damit diese Potenziale gehoben werden k{\"o}nnen, bedarf es einerseits der M{\"o}glichkeit der Kostenanrechnung im Rahmen der Netznutzungsentgelte, andererseits eines Anreizsystems, sinnvoll und sorgsam mit Q umzugehen. Grunds{\"a}tzlich ist vorher gr{\"u}ndlich zu untersuchen, ob und ab welchem Zeitpunkt die Liberalisierung der Blindleistung zielf{\"u}hrend ist und wie im Detail die Liberalisierung der Blindleistung auszugestalten w{\"a}re.}, language = {de} } @inproceedings{KrausBrueckl, author = {Kraus, Hermann and Br{\"u}ckl, Oliver}, title = {Use and Programmatic Extension of PowerFactory for the Implementation of Automated Network Planning at the Distribution Grid Level}, series = {2020 10th International Conference on Advanced Computer Information Technologies (ACIT): 16-18 Sept. 2020}, booktitle = {2020 10th International Conference on Advanced Computer Information Technologies (ACIT): 16-18 Sept. 2020}, publisher = {IEEE}, doi = {10.1109/ACIT49673.2020.9208900}, pages = {731 -- 736}, abstract = {In this paper it is presented how the network calculation program PowerFactory is used to implement automated network planning algorithms. PowerFactory's internal functions and data sets are discussed and it is shown how the functions and data sets have been extended by specially developed scripts to enable the automation of network planning steps. Finally, the methodology applied to calculate grid use cases is briefly discussed.}, language = {en} } @incollection{SternerBreuerDreesetal., author = {Sterner, Michael and Breuer, Christopher and Drees, Tim and Eckert, Fabian and Maaz, Andreas and Pape, Carsten and Rotering, Niklas and Thema, Martin}, title = {Speicherbedarf in der Stromversorgung}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_3}, pages = {53 -- 140}, subject = {Speicherbedarf}, language = {de} } @inproceedings{RauchBruecklEngel, author = {Rauch, Johannes and Br{\"u}ckl, Oliver and Engel, Bernd}, title = {Analysis and optimization of the steady state voltage deviation demand for reactive power planning using installed reactive power sources}, series = {NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage Systems, 26-27 September 2022, Hamburg}, booktitle = {NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage Systems, 26-27 September 2022, Hamburg}, editor = {Schulz, Detlef}, publisher = {VDE-Verlag}, address = {Berlin}, isbn = {978-3-8007-5983-5}, issn = {2510-6902}, pages = {175 -- 182}, abstract = {The provision of reactive power is one option for maintaining the grid voltage, that is defined as an ancillary service in Germany. This paper presents an approach for determining deficient voltage deviation demands within an electrical grid for long term reactive power planning investigations. In contrast to previous approaches, which evaluate the Q-behavior of extended ward elements or grid assets, voltage deviations are analyzed bus-specifically. So further reactive power planning investigations are able to scale and optimize additional reactive power sources directly on planning voltage limits using load flow sensitivity techniques. The focus lies on the analysis of the steady state demand at base case conditions. Therefore, a grid planning process is conceptualized. An optimal power flow algorithm based on Differential Evolution is used for an optimal reactive power dispatch of installed reactive power sources, e. g. reactive power compensation systems or (renewable) energy sources to minimize the total voltage deviation according to voltage limits of Transmission System Operators planning principles. Methodological and processuals specifications as well as an application use case with an exemplary transmission system are presented in this paper.}, language = {en} } @article{ThemaWeidlichHoerletal., author = {Thema, Martin and Weidlich, Tobias and H{\"o}rl, Manuel and Bellack, Annett and M{\"o}rs, Friedemann and Hackl, Florian and Kohlmayer, Matthias and Gleich, Jasmin and Stabenau, Carsten and Trabold, Thomas and Neubert, Michael and Ortloff, Felix and Brotsack, Raimund and Schmack, Doris and Huber, Harald and Hafenbradl, Doris and Karl, J{\"u}rgen and Sterner, Michael}, title = {Biological CO2-Methanation: An Approach to Standardization}, series = {Energies}, volume = {12}, journal = {Energies}, number = {9}, publisher = {MDPI}, doi = {10.3390/en12091670}, pages = {1 -- 32}, abstract = {Power-to-Methane as one part of Power-to-Gas has been recognized globally as one of the key elements for the transition towards a sustainable energy system. While plants that produce methane catalytically have been in operation for a long time, biological methanation has just reached industrial pilot scale and near-term commercial application. The growing importance of the biological method is reflected by an increasing number of scientific articles describing novel approaches to improve this technology. However, these studies are difficult to compare because they lack a coherent nomenclature. In this article, we present a comprehensive set of parameters allowing the characterization and comparison of various biological methanation processes. To identify relevant parameters needed for a proper description of this technology, we summarized existing literature and defined system boundaries for Power-to-Methane process steps. On this basis, we derive system parameters providing information on the methanation system, its performance, the biology and cost aspects. As a result, three different standards are provided as a blueprint matrix for use in academia and industry applicable to both, biological and catalytic methanation. Hence, this review attempts to set the standards for a comprehensive description of biological and chemical methanation processes.}, language = {en} } @incollection{SternerEckertHenningetal.2017, author = {Sterner, Michael and Eckert, Fabian and Henning, Hans-Martin and Trost, Tobias}, title = {Speicherbedarf im Verkehrs- und Chemiesektor}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_5}, pages = {169 -- 192}, year = {2017}, subject = {Speicherbedarf}, language = {de} } @incollection{SternerThema, author = {Sterner, Michael and Thema, Martin}, title = {Vergleich der Speichersysteme}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_12}, pages = {645 -- 682}, subject = {Energiespeicher}, language = {de} } @incollection{SternerStadlerEckertetal., author = {Sterner, Michael and Stadler, Ingo and Eckert, Fabian and Gerhardt, Norman and von Olshausen, Christian and Thema, Martin and Trost, Tobias}, title = {Speicherintegration zur Kopplung unterschiedlicher Energiesektoren}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_14}, pages = {769 -- 818}, subject = {Energieversorgung}, language = {de} } @incollection{SternerBauerCrotoginoetal., author = {Sterner, Michael and Bauer, Franz and Crotogino, Fritz and Eckert, Fabian and von Olshausen, Christian and Teichmann, Daniel and Thema, Martin}, title = {Chemische Energiespeicher}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_8}, pages = {327 -- 493}, subject = {Energiespeicher}, language = {de} } @inproceedings{MalzSteffensKrenkel, author = {Malz, Sebastian and Steffens, Oliver and Krenkel, Walter}, title = {Solaraktive Fassaden im Bestandsbau}, series = {Bauphysiktage 2019 in Weimar - Bauphysik in Forschung und Praxis, 25. und 26. September 2019, Bauhaus-Universit{\"a}t Weimar}, booktitle = {Bauphysiktage 2019 in Weimar - Bauphysik in Forschung und Praxis, 25. und 26. September 2019, Bauhaus-Universit{\"a}t Weimar}, editor = {V{\"o}lker, Conrad and Kornadt, Oliver and Jentsch, Mark and Vogel, Albert}, isbn = {978-3-00-063821-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-20464}, pages = {127 -- 129}, abstract = {Im Rahmen des Forschungsprojektes MAGGIE, das am Beispiel des historischen Quartiers Margaretenau in Regensburg innovative L{\"o}sungen f{\"u}r modernes und bezahlbares Wohnen erforscht, soll {\"u}ber eine solaraktive Fassade Sonnenw{\"a}rme im Bestandsmauerwerk eingespeichert werden, um so den Energiebedarf des Geb{\"a}udes zu reduzieren.}, language = {de} } @article{LiLange, author = {Li, Liwen and Lange, Klaus W.}, title = {Planning Principles for Integrating Community Empowerment into Zero-Net Carbon Transformation}, series = {smart cities}, volume = {2023}, journal = {smart cities}, number = {6}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/smartcities6010006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-57765}, pages = {100 -- 122}, abstract = {The adoption of the UN 2030 Agenda and the Sustainable Development Goals is a landmark in international sustainability politics. For example, Europe has set ambitious targets to achieve 100 climate-neutral and smart cities by 2030. However, numerous case studies from different countries have found that accelerating the transition to net-zero carbon emissions is easily hampered by the lack of a coherent systems framework, and that implementation gaps remain at the community level. These barriers are often due to a lack of an adequate end-user (i.e., household) input and early planning participation. This work therefore aims to improve on conventional planning methods that do not reflect innovative technologies with uncertainty and may not be applicable due to the lack of community empowerment, which is a dynamic learning and intervention opportunity for end-users at different planning stages (i.e., outreach, survey, planning, implementation, management, and maintenance). Using the lessons learned from participatory action research, whereby the author was involved as a project director throughout the planning and design process, we identified a six-step cycle principle. The steps are (1) collective action commitments, (2) local values and resource identification, (3) carbon footprint inventory, (4) optimized integration of environment, economy, and energy action plans, (5) Flexible strategic energy system plans, and (6) digital performance monitoring. Ultimately, the outcomes provide application support for policymakers and planners and stimulate community engagement to contribute to the achievement of zero net carbon emissions.}, language = {en} } @inproceedings{BruecklKrpalRiepl, author = {Br{\"u}ckl, Oliver and Krpal, Ondrej and Riepl, Markus}, title = {Influence of wind and solar energy on the frequency of switching operations of On-Load Tap-Changers (OLTC)}, series = {Proceedings of the 13th International Scientific Conference Electric Power Engineering 2012, EPE 2012; Vol. 2}, booktitle = {Proceedings of the 13th International Scientific Conference Electric Power Engineering 2012, EPE 2012; Vol. 2}, publisher = {EPE}, address = {Brno, Czech Republic}, organization = {Brno University of Technology / Faculty of Electrical Engineering and Communication Department of Electrical Power Engineering and Centre for Research and Utilization of Renewable Energy}, pages = {719 -- 722}, language = {en} } @incollection{SternerEckertGerhardtetal., author = {Sterner, Michael and Eckert, Fabian and Gerhardt, Norman and Henning, Hans-Martin and Palzer, Andreas}, title = {Speicherbedarf in der W{\"a}rmeversorgung}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_4}, pages = {141 -- 168}, subject = {Energiespeicher}, language = {de} } @techreport{Brueckl, author = {Br{\"u}ckl, Oliver}, title = {Hemmnisse im Verteilnetzausbau und deren {\"U}berwindung}, publisher = {INA - Institut f{\"u}r Netz- und Anwendungstechnik GmbH}, address = {Waldm{\"u}nchen}, doi = {10.35096/othr/pub-6043}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-60438}, pages = {84}, abstract = {Die Bundesregierung hat ambitionierte Ausbaupfade f{\"u}r die Windenergie und Photovoltaik festgelegt. Allerdings gef{\"a}hrdet vor allem der Verteilnetzausbau und der Netzanschluss der Erneuerbare-Energien-Anlagen (EE-Anlagen) die Erreichung dieser hochgesteckten Ziele. In einem Gutachten im Auftrag der Fraktion von B{\"u}ndnis 90/DIE GR{\"U}NEN im Bayerischen Landtag identifiziert Prof. Dr.-Ing. Oliver Br{\"u}ckl die wesentlichen Hemmnisse f{\"u}r den beschleunigten Verteilnetzausbau und den Netzanschluss f{\"u}r EE-Anlagen und diskutiert L{\"o}sungsans{\"a}tze in folgenden Bereichen: Regulierungsrahmen f{\"u}r die Verteilnetzbetreiber, Genehmigungsverfahren von Netzausbauprojekten, Praxis der Netzintegration von EE-An lagen, Personalkapazit{\"a}ten, Beschaffung von Betriebsmitteln und Bau von Anlagen, Zertifizierungsprozess f{\"u}r den Netzanschluss von EE-Anlagen. Im Rahmen des Gutachtens wurden ca. 35 Interviews mit verschiedenen Stakeholdern gef{\"u}hrt: Netzbetreiber und Stadtwerke, Projektierer*innen, Herstellerindustrie, Verb{\"a}nde und Beh{\"o}rden.}, language = {de} } @article{BruecklDalissonStrohmayeretal., author = {Br{\"u}ckl, Oliver and Dalisson, Nils and Strohmayer, Bernhard and Haslbeck, Matthias}, title = {Spannungshaltungsmaßnahmen im Verteilungsnetz : Systemvergleich}, series = {EW : Magazin f{\"u}r die Energie-Wirtschaft}, volume = {113}, journal = {EW : Magazin f{\"u}r die Energie-Wirtschaft}, number = {6}, publisher = {VWEW-Energieverl.}, address = {Frankfurt am Main}, issn = {1619-5795}, pages = {66 -- 69}, abstract = {Verteilungsnetzbetreibern stehen mittlerweile viele Maßnahmen zur Behebung des Spannungsbandproblems zur Verf{\"u}gung. Innovative Konzepte wie der regelbare Ortsnetztransformator werden in vielen Pilotprojekten erprobt. Unklar ist jedoch noch, welche Maßnahmen beziehungsweise Kombinationen langfristig wirtschaftlich am g{\"u}nstigsten sind. Die Ostbayerische Technische Hochschule Regensburg untersucht daher in einem Forschungsprojekt verschiedene Maßnahmen, um sie unter wirtschaftlichen, technischen und energetischen Gesichtspunkten bewerten zu k{\"o}nnen. Der Beitrag untersucht am Beispiel des Netzmodells eines Dorfnetzes mit zahlreichen Photovoltaikanlagen unterschiedliche Szenarien f{\"u}r die Spannungshaltung, wobei u. a. Maßnahmen wie die Parallelverkabelung, das Einspeisemanagement durch Spitzenlastkappung, die Spannungs-Blindleistungsregelung durch die Erzeugungsanlagen sowie ein RONT (regelbarer Ortsnetztransformator) betrachtet werden. Dabei zeigt sich, dass es keine Maßnahme gibt, die in allen Belangen die g{\"u}nstigste L{\"o}sung ist. Es zeichnet sich jedoch ab, dass der RONT in vielen F{\"a}llen (abh{\"a}ngig vom Durchdringungsgrad) die g{\"u}nstigste oder zumeist eine g{\"u}nstige L{\"o}sung zur Erh{\"o}hung der Netzanschlusskapazit{\"a}t darstellt.}, language = {de} } @inproceedings{SchweibererRauchBrueckl, author = {Schweiberer, Philipp and Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Long-term analysis of industrial reactive power potentials with consideration of plant-internal grid restrictions using the example of an industrial plant in a distribution grid}, series = {NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage Systems, 26-27 September 2022, Hamburg}, booktitle = {NEIS 2022; Conference on Sustainable Energy Supply and Energy Storage Systems, 26-27 September 2022, Hamburg}, editor = {Schulz, Detlef}, publisher = {VDE-Verlag}, address = {Berlin}, isbn = {978-3-8007-5983-5}, issn = {2510-6902}, pages = {51 -- 56}, abstract = {Since conventional generation plants provide a considerable share of reactive power but are gradually being shut down due to energy transition, leading to power deficits at the transmission grid level, new concepts for the supply of reactive power must be developed. As one possibility for the latter, industrial plants in the distribution grid are considered suitable, as their reactive power potentials can contribute to voltage maintenance and thus to a grid- or system-serving behavior. In this paper, the determination of reactive power potentials provided by industrial compensation systems (ICS) is presented. An industrial plant in the medium voltage grid, with three installed ICSs, is investigated. The potentials are determined and described based on their time characteristics, which provide information about the occurrence and distribution of inductive and capacitive potentials. A grid simulation of the investigated industrial grid is used to analyze the effects of retrieving the reactive power potentials regarding equipment utilizations and voltage limits.}, language = {en} } @inproceedings{KrausBrueckl, author = {Kraus, Hermann and Br{\"u}ckl, Oliver}, title = {Concept for the Use of an Automated Network-Planning in the Distribution Grid Level with Coordination of Various Grid Expansion Measures}, series = {NEIS 2019 : Conference on Sustainable Energy Supply and Energy Storage Systems, Hamburg 19.09.2019 - 20.09.2019}, booktitle = {NEIS 2019 : Conference on Sustainable Energy Supply and Energy Storage Systems, Hamburg 19.09.2019 - 20.09.2019}, editor = {Schulz, Detlef}, isbn = {978-3-8007-5152-5}, pages = {161 -- 165}, abstract = {In this thesis, a concept for the automated use of network planning processes, which is part of the decision support system developed in the framework of the EU project CrossEnergy, is presented. This publication focuses on the automatic processing of input data and subsequent network modeling as well as the coordination of network extension measures for the systematic solution of static voltage and current problems. Different variants are calculated in order to be able to compare the design technologies.}, language = {en} } @inproceedings{NonnErdelenPepplerWesseletal., author = {Nonn, Aida and Erdelen-Peppler, Marion and Wessel, Waldemar and Mahn, Denise}, title = {How reliable are the current testing procedures for the safety assurance against crack propagation in seamless gas pipelines}, series = {Proceedings of the ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering (OMAE2014), Volume 4A: Structures, Safety and Reliability, June 8-13, 2014, San Francisco, USA}, booktitle = {Proceedings of the ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering (OMAE2014), Volume 4A: Structures, Safety and Reliability, June 8-13, 2014, San Francisco, USA}, doi = {10.13140/2.1.3190.6567}, abstract = {The worldwide growing energy demand with the exploration of new gas fields has promoted the development of high toughness seamless pipeline steels which should sustain the increasing demands resulting from the complex loading situations. One of the most important prerequisites for safe installation and operation of long distance gas transmission pipelines is the detailed knowledge and characterization of their fracture performance for specific applications. However, recent industry experience has revealed concerns related to the limitations and reliability of current test methods for brittle-to-ductile transition evaluation. Regarding the transition temperature evaluation, the critical issues involve Drop-Weight Tear Testing (DWTT) and full-scale West-Jefferson (WJ) test applied to the smaller pipes with diameter less than 500mm. The DWTT leads frequently to invalid results in terms of abnormal fracture appearance and inverse fracture occurrence. It is still not clear if this behavior is only owed to a testing effect, which material characteristics cause it and how far it reflects the full-scale behavior. Similar observations were made for the West-Jefferson tests, which could not be assessed in the standard manner either. Again, the question was towards testing effects and the behavior of the pipeline transporting gaseous media remains unanswered. Therefore, this paper aims at identifying open questions on basis of a literature study and own experimental results and showing possible ways forward in demonstrating safety in design against propagating fracture.}, language = {en} } @inproceedings{NonnParedesNordhagenetal., author = {Nonn, Aida and Paredes, Marcelo and Nordhagen, H. O. and Munkejord, S. T. and Wierzbicki, Tomasz}, title = {Challenges in fluid-structure modeling of crack propagation and arrest in modern steel pipelines}, series = {14th International Congress on Fracture (ICF14), 18-23 June 2017, Rhodes, Greece}, booktitle = {14th International Congress on Fracture (ICF14), 18-23 June 2017, Rhodes, Greece}, pages = {1351 -- 1352}, language = {en} } @inproceedings{KarbasianGrossWeegeNonnetal., author = {Karbasian, H. and Groß-Weege, J. and Nonn, Aida and Zimmermann, S. and Kalwa, Christoph}, title = {Assessment of collapse resistance of UOE pipes - comparison of full-scale and ring collapse tests}, series = {Proceedings of the 10th International Pipeline Conference 2014 (IPC 2014), September 29 - October 3, 2014, Calgary, Alberta, Canada}, booktitle = {Proceedings of the 10th International Pipeline Conference 2014 (IPC 2014), September 29 - October 3, 2014, Calgary, Alberta, Canada}, language = {en} } @inproceedings{NonnKalwa, author = {Nonn, Aida and Kalwa, Christoph}, title = {Analysis of dynamic ductile fracture propagation in pipeline steels}, series = {6th Pipeline Technology Conference (2013), Ostend, Belgium}, booktitle = {6th Pipeline Technology Conference (2013), Ostend, Belgium}, doi = {10.13140/2.1.4370.3046}, abstract = {Analysis of dynamic ductile fracture propagation in pipeline steels: a damage-T IS A WELL-ESTABLISHED fact that the successful application of new generation of high-strength steel grades for long-distance gas transmission depends strongly on full understanding and appropriate characterization of fracture resistance. A damage mechanics approach has found to be a very promising tool in supporting the experimental characterization of ductile fracture propagation. The major advantage of this approach lies in the consideration of the influence of local stress and strain variables on the damage evolution and thus its capability to describe the fracture resistance of the pipelines with different stress triaxiality level by using the same set of parameters. However, the wider application of this approach has been limited due to the issues such as reliable determination of input parameters and required material properties, mesh size dependence, etc.. The objective of this paper is to characterize dynamic ductile fracture resistance of X65 and X80 pipeline materials and to demonstrate the potential of damage mechanics approach for the simulation of dynamic fracture propagation by using two damage models: (1) Cohesive Zone (CZ) model and (2) Gurson-Tvergaard-Needleman (GTN) model. In the first step, results from quasi-static and dynamic tensile tests are used to describe plasticity in terms of flow curves. The calibration of input parameters for both models is performed by using the load-deformation curves from quasi-static tests on non-standard drop-weight tear (DWT) specimens with pre-fatigued crack. b. In the next step, estimated damage model parameters are verified by means of the dynamic tests on the pressed and Chevron notch DWT specimens. Different amounts of crack growth are established by varying the drop height. The experimental fracture resistance is quantified in terms of J-integral at specific crack length. The numerical results are evaluated with respect to global load-deformation and fracture resistance behavior. Furthermore, damage simulations are applied for quantification of local stress conditions in order to identify the major factors controlling the crack propagation. The results reported here serve as a basis for better understanding of fracture performance in dependences of geometry and material properties.}, language = {en} } @inproceedings{NonnErdelenPepplerWesseletal., author = {Nonn, Aida and Erdelen-Peppler, Marion and Wessel, Waldemar and Harksen, Silke and Mahn, Denise}, title = {How to assure fracture-propagation control for seamless gas pipelines?}, series = {Proceedings of the 2014 10th International Pipeline Conference (IPC2014), Volume 3: Operations, Monitoring, and Maintenance, Materials and Joining, September 29-October 3, 2014, Calgary, Canada}, booktitle = {Proceedings of the 2014 10th International Pipeline Conference (IPC2014), Volume 3: Operations, Monitoring, and Maintenance, Materials and Joining, September 29-October 3, 2014, Calgary, Canada}, doi = {10.1115/IPC2014-33169}, abstract = {Fracture propagation control in gas transmission gas pipelines belongs to the major design requirements for safe operation at high internal pressures. However, the current tests such as Drop-Weight-Tear Test (DWTT) and full-scale West-Jefferson (WJ) test reach the limits of their applicability with respect to transition temperature evaluation for seamless quenched and tempered small diameter pipes reflecting nowadays alloying concepts related to mechanical properties. Hereby, different geometry and material effects are evident which might lead to misinterpretation and unreliability of testing results. This paper aims to discuss open issues addressed in the literature and in own experimental findings with respect to reliability and transferability of testing methods, fracture parameters and their representativeness of seamless quenched and tempered pipeline behavior. By applying damage mechanics approach, it is possible to quantify the prevailing stress state and thus to understand the mechanisms controlling specific fracture appearance (ductile or brittle). Furthermore, studies were performed with objective to quantify the effect of different parameters (geometry, material and loading) on the fracture performance of the pipeline. The results from these investigations will serve as a basis for a safe pipeline design against propagating fracture.}, language = {en} } @inproceedings{NonnKalwa, author = {Nonn, Aida and Kalwa, Christoph}, title = {Simulation of ductile crack propagation in high-strength pipeline steel using damage models}, series = {9th International Pipeline Conference 2012 (IPC 2012), Calgary, Canada}, booktitle = {9th International Pipeline Conference 2012 (IPC 2012), Calgary, Canada}, doi = {10.1115/IPC2012-90653}, pages = {7}, abstract = {The performance of engineering design of high-strength steel pipelines has revealed the necessity to revise current design procedures. Therefore, an improved and detailed comprehension of fracture mechanisms and development of failure prediction tools are required in order to derive new design criteria. In last decades the most successful failure prediction tools for steel structures subjected to various type of loading can be encountered in the field of damage mechanics. This paper aims to describe ductile fracture behavior of high-strength steel pipelines by applying three different damage models, Gurson-Tvergaard-Needelman (GTN), Fracture Locus Curve (FLC) and Cohesive Zone (CZ). These models are evaluated regarding their capability to estimate ductile crack propagation in laboratory specimens and linepipe components without adjusting the calibrated parameters. It can be shown that appropriate parameter sets can be identified to reproduce load-deformation and fracture resistance curves accurately. The strain rate effect on the fracture behavior is examined by dynamic tests on the BDWT specimens. Finally, the shortcomings of the applied models are pointed out with the reference to possible extensions and modifications.}, language = {en} } @inproceedings{VoellingNonnSchneider, author = {V{\"o}lling, Alexander and Nonn, Aida and Schneider, Ingo}, title = {Anwendung des Koh{\"a}sivzonenmodells zur Abbildung von duktilem dynamischen Rissfortschritt in Gasfernleitungen}, series = {45. Tagung des AK Bruch, Berlin, Germany}, booktitle = {45. Tagung des AK Bruch, Berlin, Germany}, pages = {253 -- 262}, subject = {Ferngasleitung}, language = {de} } @inproceedings{NonnWesselSchmidt, author = {Nonn, Aida and Wessel, Waldemar and Schmidt, Tanja}, title = {Application of finite element analysis for assessment of fracture behavior of modern high toughness seamless pipeline steels}, series = {23rd International Society of Offshore and Polar Engineering 2013 (ISOPE 2013), Anchorage, USA}, booktitle = {23rd International Society of Offshore and Polar Engineering 2013 (ISOPE 2013), Anchorage, USA}, doi = {10.13140/2.1.4239.2322}, abstract = {Fracture behavior of seamless pipeline material X65Q acc. to API 5L has been studied both experimentally and numerically at different loading conditions (quasi-static vs. dynamic) and temperatures. The recent findings have shown difficulties in applying well established methods for determination of transition behavior or prediction of ductile crack arrest for the new generation of high-toughness steels. The irregular fracture performance (e.g. so-called "abnormal inverse fracture" appearance, significant scattering in ductile-to-brittle-transition-temperature region, etc.) suggests that the influence of pipe dimensions, loading parameters, crack initiation resistance as well as testing procedure on the fracture behavior has been neither understood nor properly described. This work aims to shed light on these questions regarding the applicability of conventional methods and to better illuminate most relevant parameters affecting fracture behavior of high toughness steels. To achieve this goal, experimental data basis for analysis of fracture behavior in transition and upper shelf regime has been established by conducting quasi-static fracture mechanics tests and dynamic tests on Battelle Drop Weight Tear (BDWT or DWT) specimens at different temperatures. The evaluation of obtained test results in upper shelf has been additionally complemented by numerical simulation of damage behavior. The results highlight the influence of stress conditions on fracture behavior with reference to pipe dimensions and loading conditions and, subsequently, may be used as a basis for revision of existing design methods.}, subject = {Rissfortschritt}, language = {en} } @inproceedings{KofianiNonnWierzbickietal., author = {Kofiani, Kirki and Nonn, Aida and Wierzbicki, Tomasz and Kalwa, Christoph and Walters, Carey}, title = {Experiments and fracture modeling of high-strength pipelines for high and low stress triaxiality}, series = {22nd International Society of Offshore and Polar Engineering 2012 (ISOPE 2012), Rhodes, Greece, June 2012}, booktitle = {22nd International Society of Offshore and Polar Engineering 2012 (ISOPE 2012), Rhodes, Greece, June 2012}, abstract = {This paper provides results from a comprehensive study on mechanical characterization of high-strength pipeline steel, grade X100 using experimental and numerical methods. The material was characterized for anisotropic plasticity, fracture initiation for various states of stress, (pre-cracked) fracture toughness and uncracked ductility. The experimental program included tests on flat butterfly-shaped, central hole, notched and circular disk specimens for low stress triaxiality levels; as well as tests on round notched bar specimens and SENT fracture mechanics tests, for high values of stress triaxiality. This program covered a wide range of stress conditions and demonstrated its effect on the material resistance. Parallel to the experimental study, detailed numerical investigations were carried out to simulate all different experimental tests. Using an inverse method, a 3-parameter calibration was performed on the Modified Mohr-Coulomb (MMC) fracture model. Subsequently, the predictive capabilities of the MMC were evaluated by the comparison to the fracture toughness tests results, used extensively in the pipeline industry. The capabilities of the MIT fracture model have been demonstrated on an example of high strength offshore steel, X100. The outcome of this study was not only to provide, the overall characterization of the fracture behavior of this material as an example, but also to present the methodology on how to use the MMC model as a practical tool in pipeline design.}, language = {en} } @inproceedings{NonnKalwa, author = {Nonn, Aida and Kalwa, Christoph}, title = {Failure modeling of pipeline X100 Material in temperature transition region}, series = {22nd International Society of Offshore and Polar Engineering 2012 (ISOPE 2012), Rhodes, Greece}, booktitle = {22nd International Society of Offshore and Polar Engineering 2012 (ISOPE 2012), Rhodes, Greece}, abstract = {This paper focuses on the characterization of the fracture performance of X100 material in transition temperature region using both experimental and numerical methods. The ductile fracture has been analyzed using tests on round notched bar specimens and standard fracture mechanics tests performed at room temperature. In previous publications the damage model Gurson-Tvergaard-Needleman (GTN) has been applied and verified by existing experimental data to describe ductile fracture behavior. The brittle fracture and the fracture in temperature transition region have been studied by means of deep and shallow notched SENB specimens at two different temperatures T=- 80°C and -40°C. Besides elastic-plastic analyses to quantify constraint levels for different initial crack configurations at the onset of cleavage fracture, the brittle failure has been described using modified Beremin model. The influence of the stable crack growth on the cleavage failure probability in temperature transition region has been captured by coupling the ductile fracture model (GTN) with the modified Beremin model. Finally, examples have been presented for the practical application of the numerical results on the fracture assessment of the flawed high-strength pipelines.}, language = {en} } @inproceedings{NonnKalwa, author = {Nonn, Aida and Kalwa, Christoph}, title = {The effect of microstructure, strain hardening and strain rate on the fracture behavior of high strength pipeline steels}, series = {2nd International Conference on Material Modelling (ICMM2), 31th August - 2nd September, 2011 at Mines Paris Tech, France}, booktitle = {2nd International Conference on Material Modelling (ICMM2), 31th August - 2nd September, 2011 at Mines Paris Tech, France}, language = {en} } @inproceedings{NonnKalwa, author = {Nonn, Aida and Kalwa, Christoph}, title = {Application of damage mechanics approach for crack propagation in pipeline}, series = {19th Biennial Joint Technical Meeting (JTM) on Pipeline Research, April 29 - May 3, 2013, Sydney, Australia}, booktitle = {19th Biennial Joint Technical Meeting (JTM) on Pipeline Research, April 29 - May 3, 2013, Sydney, Australia}, language = {en} } @inproceedings{NonnKalwa, author = {Nonn, Aida and Kalwa, Christoph}, title = {Application of probabilistic fracture mechanics for safety assessment of longitudinally welded linepipes}, series = {6th Pipeline Technology Conference (2013), Ostend, Belgium}, booktitle = {6th Pipeline Technology Conference (2013), Ostend, Belgium}, language = {en} } @techreport{NeidhartLerchWiesingeretal., author = {Neidhart, Thomas and Lerch, Maximilian and Wiesinger, Doris and Zrenner, Louis}, title = {Kompakte {\"U}bertragungsleitungen f{\"u}r hohe Gleichspannungen: Langzeituntersuchungen an einer erdverlegten Versuchsanlage}, doi = {10.35096/othr/pub-2173}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-21730}, pages = {62, 58}, abstract = {Durch den Ausstieg aus der Verstromung fossiler Energietr{\"a}ger und der daraus resultierenden dezentralen Stromerzeugung ist ein Aus- bzw. Umbau des deutschen {\"U}bertragungsnetzes erforderlich. Weil aus der dezentralen Energieerzeugung große Trassenl{\"a}ngen resultieren, welche bei Wechselstrom zu Blindleistungsproblematiken f{\"u}hren, wird dort vermehrt auf Hochspannungs-Gleichstrom-{\"U}bertragung zur{\"u}ckgegriffen. Im Rahmen des Forschungsprojekts DC CTL DBI (direct current compact transmission line - directly buried investigastions) wurde ein gasisolierte HG{\"U}-Leiter (GIL) erdverlegt und bei st{\"a}ndigem Monitoring {\"u}ber umfangreiche Sensorik einem Langzeitversuch unterzogen. Anstelle einer klassischen Sandbettung kam ein zeitweise fließf{\"a}higer, selbstverdichtender Verf{\"u}llbaustoff (ZFSV) zum Einsatz. Somit k{\"o}nnen Sch{\"a}den an der {\"U}bertragungsleitung infolge Verdichtungsaufwand vermieden und gleichzeitig bessere Bodeneigenschaften hinsichtlich der W{\"a}rme- und Wassertransportprozesse erreicht werden.}, language = {de} } @incollection{SternerStadler, author = {Sterner, Michael and Stadler, Ingo}, title = {Energiespeicher im Wandel der Zeit}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_1}, pages = {3 -- 24}, subject = {Energiespeicher}, language = {de} } @incollection{SternerStadlerEckertetal., author = {Sterner, Michael and Stadler, Ingo and Eckert, Fabian and Thema, Martin}, title = {Speicherintegration in einzelnen Energiesektoren}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48893-5}, doi = {10.1007/978-3-662-48893-5_13}, pages = {685 -- 767}, subject = {Energiespeicher}, language = {de} } @incollection{SternerBauer, author = {Sterner, Michael and Bauer, Franz}, title = {Definition und Klassifizierung von Energiespeichern}, series = {Energiespeicher - Bedarf, Technologien, Integration}, booktitle = {Energiespeicher - Bedarf, Technologien, Integration}, edition = {2. Auflage}, publisher = {Springer Vieweg}, address = {Berlin ; Heidelberg}, isbn = {978-3-662-48892-8}, doi = {10.1007/978-3-662-48893-5_2}, pages = {25 -- 49}, subject = {Energiespeicher}, language = {de} } @inproceedings{HopfenspergerDaubnerHerrmannetal., author = {Hopfensperger, Bernhard and Daubner, Andreas and Herrmann, Fabian and Hopkins, Andrew and Mellor, Phil}, title = {Investigation of Shifted PWM Methods for a Dual Three-Phase System to Reduce Capacitor RMS Current}, series = {PCIM Europe Digital Days 2020: International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management: 07.-08.07.2020, Online [proceedings]}, booktitle = {PCIM Europe Digital Days 2020: International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management: 07.-08.07.2020, Online [proceedings]}, publisher = {VDE-Verlag}, address = {Berlin, Offenbach}, isbn = {978-3-8007-5245-4}, pages = {124 -- 131}, abstract = {Mild hybrid automotive topologies containing a 48V high power (>15 kW) electric drive system demand a high integration of power electronics and electrical machine. A multi-phase motor winding topology helps to keep the per-phase operating currents to a reasonable level. Close integration and multi-phase system have led to a drive system with dual 3-phase systems supplied by a common 48V DC-link, which allows to shift PWM patterns for reduction of DC-link capacitor ripple current and size. This paper derives some basic rules for combinations of common PWM methods for dual 3-phase systems without magnetic cross-coupling. Experimental measurements verify simulated results.}, subject = {Elektroantrieb}, language = {en} } @inproceedings{GrauvoglStauderHopfenspergeretal., author = {Grauvogl, Dominik and Stauder, Peter and Hopfensperger, Bernhard and Gerling, Dieter}, title = {Multiphysics Design of a Wound Field Synchronous Machine with Magnetic Asymmetry}, series = {Proceedings of the 2021 IEEE International Electric Machines \& Drives Conference (IEMDC): 17-20 May 2021, Hartford, CT, USA}, booktitle = {Proceedings of the 2021 IEEE International Electric Machines \& Drives Conference (IEMDC): 17-20 May 2021, Hartford, CT, USA}, doi = {10.1109/IEMDC47953.2021.9449564}, abstract = {In this paper a multiphysics development method is used for designing a novel wound field synchronous machine of the future generation of high voltage traction drives. This method covers the domains of electromagnetics, the mechanical strength, thermal behavior and the magnetic noise. It is shown that the proposed novel asymmetric design with a circular flux barrier in combination with an asymmetric pole offset is fulfilling the requirements according to performance and torque ripple. A fatigue strength rotor mechanic concept is included. A hybrid cooling concept consisting of a water jacket cooled stator and air cooled rotor ensures the needed continuous power. Unacceptable noise levels are excluded by investigating the equivalent radiated power (ERP) level due to radial forces in the air gap. Finally, the multi-physical workflow resulted in a fully developed component with a high degree of maturity.}, language = {en} } @inproceedings{GrauvoglKrabinskiStauderetal., author = {Grauvogl, Dominik and Krabinski, Jeffrey and Stauder, Peter and Hopfensperger, Bernhard and Gerling, Dieter}, title = {NVH Comparison of a Novel Wound Field Synchronous Machine with Magnetic Asymmetry with a PSM for a HV Electric Drive}, series = {2021 JSAE Annual Congress (Spring) Proceedings; online meeting (No.76-21)}, booktitle = {2021 JSAE Annual Congress (Spring) Proceedings; online meeting (No.76-21)}, publisher = {JSAE}, abstract = {This paper shows how magnetic noises can be reduced with a wound field synchronous machine (WFSM) with magnetic asymmetry compared to a permanent magnet synchronous machine (PSM), operating at base speed range and full load. In order to reproduce a real noise behavior, the two rotor types are operated in a complete electric drive unit (EDU) consisting of an electric motor, gearbox, inverter and overall housing. In the concept study, the noise characteristics of the two electric machines is evaluated and compared via mechanical finite element method (FEM) simulations using the equivalent radiated power (ERP) level and Campbell diagrams. Furthermore, it is shown that critical frequency orders can already be identified by the analysis of the magnetic force density from the electromagnetic design without computationally intensive ERP calculations. In this context, the ERP investigations have shown that the unique feature of the magnetically asymmetric WFSM is the reduction of the slot harmonics. At the current state of the art, the slot harmonics can only be reduced with a rotor skewing. The disadvantage of this is a reduction in performance and a more expensive production. It is also remarkable that the magnetic asymmetry reduces the slot harmonics more than the rotor skewing in the PSM. In addition, both machines are still considered with a short-pitched stator winding to optimize the overall noise level by reducing the 24th frequency order.}, subject = {Elektroantrieb}, language = {en} } @inproceedings{LangSteinbornSteffensetal., author = {Lang, Christian and Steinborn, Florian and Steffens, Oliver and Lang, Elmar Wolfgang}, title = {Electricity Load Forecasting - An Evaluation of Simple 1D-CNN Network Structures}, series = {International Conference on Time Series and Forecasting (ITISE 2019), Proceedings of Papers Vol. 2, 25-27 September 2019, Granada (Spain)}, booktitle = {International Conference on Time Series and Forecasting (ITISE 2019), Proceedings of Papers Vol. 2, 25-27 September 2019, Granada (Spain)}, isbn = {978-84-17970-78-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-16649}, pages = {797 -- 806}, abstract = {This paper presents a convolutional neural network (CNN)which can be used for forecasting electricity load profiles 36 hours intothe future. In contrast to well established CNN architectures, the inputdata is one-dimensional. A parameter scanning of network parameters isconducted in order to gain information about the influence of the kernelsize, number of filters, and dense size. The results show that a goodforecast quality can already be achieved with basic CNN architectures.The method works not only for smooth sum loads of many hundredconsumers, but also for the load of apartment buildings}, language = {en} } @incollection{LangSteinbornSteffensetal., author = {Lang, Christian and Steinborn, Florian and Steffens, Oliver and Lang, Elmar Wolfgang}, title = {Applying a 1D-CNN Network to Electricity Load Forecasting}, series = {Theory and Applications of Time Series Analysis}, booktitle = {Theory and Applications of Time Series Analysis}, editor = {Valenzuela, O. and Rojas, F. and Herrera, L.J. and Pomares, H. and Rojas, I.}, publisher = {Springer}, doi = {10.1007/978-3-030-56219-9_14}, pages = {205 -- 218}, abstract = {This paper presents a convolutional neural network (CNN) which can be used for forecasting electricity load profiles 36 hours into the future. In contrast to well established CNN architectures, the input data is one-dimensional. A parameter scanning of network parameters is conducted in order to gain information about the influence of the kernel size, number of filters and number of nodes. Furthermore, different dropout methods are applied to the CNN and are evaluated. The results show that a good forecast quality can already be achieved with basic CNN architectures, the dropout improves the forecast. The method works not only for smooth sum loads of many hundred consumers, but also for the load of single apartment buildings.}, language = {en} } @inproceedings{KeimNonnLenzetal., author = {Keim, Vincent and Nonn, Aida and Lenz, D. and Brinnel, Viktoria and M{\"u}nstermann, Sebastian}, title = {Simulation of the ductile fracture behaviour of high toughness pipeline steels using combined damage models}, series = {Proceedings of the conference on Technology for future and ageing piplines, Ghent, Belgium}, booktitle = {Proceedings of the conference on Technology for future and ageing piplines, Ghent, Belgium}, language = {en} } @inproceedings{ArrietaCastroWeberRill, author = {Arrieta Castro, Abel and Weber, Hans Ingo and Rill, Georg}, title = {Design an integrate vehicle control based-on hierarchical architecture for improve the performance of ground vehicles}, series = {COBEM2015 : 23rd ABCM International Congress of Mechanical Engineering, December 6-11, 2015, Rio de Janeiro, RJ, Brazi}, booktitle = {COBEM2015 : 23rd ABCM International Congress of Mechanical Engineering, December 6-11, 2015, Rio de Janeiro, RJ, Brazi}, organization = {Associa{\c{c}}{\~a}o Brasileira de Engenharia e Ci{\^e}ncias Mec{\^a}nicas}, doi = {10.20906/cps/cob-2015-1970}, language = {en} } @inproceedings{DessortChucholowskiRill, author = {Dessort, Ronnie and Chucholowski, Cornelius and Rill, Georg}, title = {Parametrical approach for modeling of tire forces and torques in TMeasy 5}, series = {16. Internationales Stuttgarter Symposium, Automobil- und Motorentechnik, Bd. 1}, booktitle = {16. Internationales Stuttgarter Symposium, Automobil- und Motorentechnik, Bd. 1}, editor = {Bargende, Michael and Reuss, Hans-Christian and Wiedemann, Jochen}, publisher = {Springer}, address = {Wiesbaden}, isbn = {978-3-658-13254-5}, doi = {10.1007/978-3-658-13255-2_31}, pages = {435 -- 449}, abstract = {For the dynamic simulation of on-road vehicles, the model-element "tire/road" is of special importance, according to its influence on the achievable results. Sufficient description of the interaction between tire and road is one of the most challenging tasks of vehicle modeling. Two groups of tire models can be classified: handling models and structural or high-frequency models. Usually, various assumptions are made in modeling vehicles as multibody systems. Therefore, in the interest of balanced modeling, the precision of the complete vehicle model should stand in reasonable relation to the performance of the applied tire model. Handling tire models are characterized by a useful compromise between user friendliness, model complexity, and efficiency in computation time on the one hand, and precision in representation on the other hand.}, language = {en} } @inproceedings{Briem, author = {Briem, Ulrich}, title = {Fatigue Behaviour of Rope Wires}, series = {Proceedings of the OIPEEC Conference, La Rochelle, France, 12th - 15th March 2019}, booktitle = {Proceedings of the OIPEEC Conference, La Rochelle, France, 12th - 15th March 2019}, editor = {Dohm, Martin}, publisher = {OIPEEC}, abstract = {The rope curve line of a tensioned rope can be described by means of the catenary curve. Opposed to that, the curved line of a free bent rope cannot be described by an analytical function. Practical applications of free bending are for example at tail ropes at the bottom of shaft in rope drives with traction sheaves. The question whether the maximum diameter of rope loop is small enough for the diameter of the shaft is highly interesting. In [1] a method was presented to calculate the curved line of free bent ropes numerically by help of energy methods. An analytical description of rope curve line would be very helpful. Beginning with the structure of a rope curve line of tensioned rope (catenary curve) and considering the influence of bending stiffness, the structure of an analytical equation for the curve line of a free bent rope will be developed. The main focus of this paper is to develop and to describe the structure of such an analytical equation. To get a first idea about the values of the constants in that analytical equation a few test results were evaluated. But these equations consider the static rope behavior only. Due to dynamic effects in the rope while running through the loop at the bottom of a shaft, pendulousness of the tail rope occurs.}, language = {en} } @inproceedings{Briem2019, author = {Briem, Ulrich}, title = {Mathematical Approach to Curve Line of free bent Ropes}, series = {Proceedings of the OIPEEC Conference, La Rochelle, France, 12th - 15th March 2019}, booktitle = {Proceedings of the OIPEEC Conference, La Rochelle, France, 12th - 15th March 2019}, editor = {Dohm, Martin}, publisher = {OIPEEC}, year = {2019}, abstract = {The rope curve line of a tensioned rope can be described by means of the catenary curve. Opposed to that, the curved line of a free bent rope cannot be described by an analytical function. Practical applications of free bending are for example at tail ropes at the bottom of shaft in rope drives with traction sheaves. The question whether the maximum diameter of rope loop is small enough for the diameter of the shaft is highly interesting. In [1] a method was presented to calculate the curved line of free bent ropes numerically by help of energy methods. An analytical description of rope curve line would be very helpful. Beginning with the structure of a rope curve line of tensioned rope (catenary curve) and considering the influence of bending stiffness, the structure of an analytical equation for the curve line of a free bent rope will be developed. The main focus of this paper is to develop and to describe the structure of such an analytical equation. To get a first idea about the values of the constants in that analytical equation a few test results were evaluated. But these equations consider the static rope behavior only. Due to dynamic effects in the rope while running through the loop at the bottom of a shaft, pendulousness of the tail rope occurs.}, language = {en} } @inproceedings{BuschmannBriem, author = {Buschmann, Knut and Briem, Ulrich}, title = {Ultra Deep Temperature Behaviour of Wire Rope and Rope Wires}, series = {Proceedings of the OIPEEC Conference, La Rochelle, France, 12th - 15th March 2019}, booktitle = {Proceedings of the OIPEEC Conference, La Rochelle, France, 12th - 15th March 2019}, editor = {Dohm, Martin}, abstract = {Mobile cranes are regularly operated in regions which experience ultra deep operating temperatures of down to -60?C (-76?F). In safety regulated work environments crane operations will be suspended simply because the lowest wire rope working temperature stated in the applicable standards is -40?C/F. Examples of ultra deep temperature wire rope application are shown in Figure 1.1 and 1.3. It should be noted that this paper is written in conjunction with a paper written by the co-author Ulrich Briem titled "Fatigue Behaviour of Rope Wires", presented and published in unison with this one. In order to analyze the behaviour under ultra deep temperature conditions, tests on wire rope as well as on rope wires were carried out. In the following, static tensile and bending test results with rope and rope wires will be reported, which were carried out in conditions of down to -95?C (-139?F) as well as at room temperature. The conclusion is that the results of these tests can be adopted to crane wire rope as well.}, language = {en} } @article{LangMonkman, author = {Lang, A. and Monkman, Gareth J.}, title = {An analysis of the electrical capacitance between two conducting spheres}, series = {Journal of Electrostatics}, volume = {108}, journal = {Journal of Electrostatics}, publisher = {Elsevier}, doi = {10.1016/j.elstat.2020.103518}, abstract = {Many modern composites consist of dielectric polymer matrices containing embedded spherical particles. These particles can be electrically conducting and often have magnetic properties. In order to accurately model and simulate such materials, precise calculation of the electrical capacitance between identically sized spheres is required. This is of particular relevance at microscopic dimensions where many smart material-based micro devices are concerned. This may appear trivial for a small number of particles. However, many methods or their analysis appear to be questionable or not applicable at reduced dimensions. In this work, the various methods of analysis are scrutinized before being compared with both simulation and direct measurements. It is surprising to note that of the many works investigated only 3 are in close agreement with both simulation and measurement. Graphical abstract This paper deals with the precise calculation of the electrical capacitance between two conducting spheres of equal, or near equal size.The calculations have been verified by both experimental measurements and simulation. Algorithms in MatLab (Octave) format have been included in the supporting information.}, language = {en} } @article{ChenZhangSongetal., author = {Chen, Rui and Zhang, Zhuo and Song, Ruizhou and Fang, Cheng and Sindersberger, Dirk and Monkman, Gareth J. and Guo, Jianglong}, title = {Time-dependent electroadhesive force degradation}, series = {Smart Materials and Structures}, volume = {29}, journal = {Smart Materials and Structures}, number = {5}, publisher = {IOP Publishing}, doi = {10.1088/1361-665X/ab79b5}, abstract = {This paper concerns a comprehensive investigation of time-dependent electroadhesion (EA) force degradation. EA shear force tests on different object materials (a PET, glass, ABS, and wood plate) have shown that force degradation was dominated by residual polarization charges trapped in the EA pad dielectric rather than in the substrate dielectric from which the object to be prehended is made. In order to explain this dynamic physical phenomenon, a model of dielectric polarization and depolarization has been proposed. According to the derived relationship between EA force and discharge time, three different methods intended to mitigate this problem has been compared: (1) the natural discharge method, (2) the high voltage resistor discharge method, and (3) the discharge prior to field polarity reversal method. These methods are useful for generating repeatable and stable EA forces, which are required for the characterization of EA pads and their subsequent employment in material handling, mobile robot crawling and climbing tasks.}, language = {en} } @article{SorokinStepanovShamoninChamonineetal., author = {Sorokin, Vladislav V. and Stepanov, Gennady V. and Shamonin (Chamonine), Mikhail and Monkman, Gareth J. and Kramarenko, Elena Yu}, title = {Magnetorheological behavior of magnetoactive elastomers filled with bimodal iron and magnetite particles}, series = {Smart materials and structures}, volume = {26}, journal = {Smart materials and structures}, number = {3}, publisher = {IOP Publishing}, doi = {10.1088/1361-665X/26/3/035019}, abstract = {Magnetoactive elastomers (MAE) based on soft silicone matrices, filled with various proportions of large diameter ( approximately 50 mu m) iron and small diameter ( approximately 0.5 mu m) magnetite particles are synthesized. Their rheological behavior in homogeneous magnetic fields up to 600 mT is studied in detail. The addition of small magnetite particles facilitates fabrication of uniformly distributed magnetic elastomer composites by preventing aggregation and sedimentation of large particles during curing. It is shown that using the proposed bimodal filler particles it is possible to tailor various magnetorheological (MR) properties which can be useful for different target applications. In particular, either absolute or relative magnetorheological effects can be tuned. The value of the damping factor as well as the range of deformation amplitudes for the linear viscoelastic regime can be chosen. The interdependencies between different MR properties of bimodal MAEs are considered. The results are discussed in the model framework of particle network formation under the simultaneous influence of external magnetic fields and mechanical deformation.}, language = {en} } @misc{ReindlErikssonNiemetzetal., author = {Reindl, Andrea and Eriksson, Lars and Niemetz, Michael and Sangyoung, Park and Meier, Hans}, title = {Control Concepts for a Decentralized Battery Management System Decentralized Battery Management System Global Control Level}, series = {16th International Renewable Energy Storage Conference (IRES2022), 20 to 22 September 2022, D{\"u}sseldorf}, journal = {16th International Renewable Energy Storage Conference (IRES2022), 20 to 22 September 2022, D{\"u}sseldorf}, publisher = {Eurosolar}, language = {en} } @inproceedings{KoernerReindlMeieretal., author = {K{\"o}rner, Patrick and Reindl, Andrea and Meier, Hans and Niemetz, Michael}, title = {A Theoretical Comparison of Different Virtual Synchronous Generator Implementations on Inverters}, series = {2022 24th European Conference on Power Electronics and Applications (EPE'22 ECCE Europe): 05-09 September 2022, Hannover, Germany}, booktitle = {2022 24th European Conference on Power Electronics and Applications (EPE'22 ECCE Europe): 05-09 September 2022, Hannover, Germany}, publisher = {IEEE}, pages = {9}, abstract = {The goal to overcome the global climate crisis leads to a rising demand for the usage of Renewable Energy Sources (RES). Decentralized control strategies are needed to allow the integration of RES into the grid. The Virtual Synchronous Generator (VSG) is proposed as a method to add virtual inertia to the grid by emulating the rotating mass of a Synchronous Generator (SG) on the control algorithm of an inverter. This paper presents the VSG control structure as well as the mathematical description in a unified form. Due to the fact that classical droop control can be seen as a special form of the VSG, their correlation is highlighted by evaluating the steady state output characteristics of the inverter. Furthermore, a theoretical comparison between different VSG topologies, including the VISMA-Method 2 and the synchronverter, is given. In order to achieve better voltage stability, principles to add virtual impedance to the inverter's output are described.}, language = {en} } @inproceedings{ParedesKeimNonnetal., author = {Paredes, Marcelo and Keim, Vincent and Nonn, Aida and Wierzbicki, Tomasz}, title = {Effect of plasticity parameter on the crack propagation in steel pipelines}, series = {Proceedings of the conference on Technology for future and ageing piplines, Ghent, Belgium}, booktitle = {Proceedings of the conference on Technology for future and ageing piplines, Ghent, Belgium}, language = {en} } @article{HaugVetterWeber, author = {Haug, Sonja and Vetter, Miriam and Weber, Karsten}, title = {Geb{\"a}udesanierung zwischen Energieeffizienz und Sozialvertr{\"a}glichkeit}, series = {TATuP - Zeitschrift f{\"u}r Technikfolgenabsch{\"a}tzung in Theorie und Praxis}, volume = {29}, journal = {TATuP - Zeitschrift f{\"u}r Technikfolgenabsch{\"a}tzung in Theorie und Praxis}, number = {3}, publisher = {oekom-Verlag}, issn = {2567-8833}, doi = {10.14512/tatup.29.3.56}, pages = {56 -- 63}, abstract = {Die Akzeptanz unter Bewohnern und Bewohnerinnen gewinnt bei hoch komplexen, technisch anspruchsvollen energetischen Sanierungen als „Innovationsmotor" zunehmend an Relevanz. Der Beitrag basiert auf zwei Fallstudien zur partizipativen Nutzereinbindung bei energetischen Sanierungen im genossenschaftlichen Wohnbau historischer Stadtquartiere in Regensburg. Neben einer sozialvertr{\"a}glichen Sanierung wurde jeweils ein hohes Maß an Energieeffizienz bei den technischen L{\"o}sungen ange-strebt. Haushaltsbefragungen und qualitative Interviews zeigen die hohe Akzeptanz von Sanierungsmaßnahmen, sofern die Senkung der Energiekosten die erh{\"o}hte Miete kompensiert. Abschließend werden Akzeptanzfaktoren wie Partizipation, Vertrauen, Sozialvertr{\"a}glichkeit und Autarkie er{\"o}rtert.}, subject = {Altbaumodernisierung}, language = {de} } @inproceedings{WeberHaug, author = {Weber, Karsten and Haug, Sonja}, title = {Automatisiertes Fahren: Evolution{\"a}re Weiterentwicklung statt Disruption}, series = {Vierte Jahreskonferenz des Netzwerks INDIGO zum Thema "Mobilit{\"a}t", 23.11.2018, , TH Deggendorf}, booktitle = {Vierte Jahreskonferenz des Netzwerks INDIGO zum Thema "Mobilit{\"a}t", 23.11.2018, , TH Deggendorf}, language = {de} } @article{BringoutErbFrikel, author = {Bringout, Ga{\"e}l and Erb, Wolfgang and Frikel, J{\"u}rgen}, title = {A new 3D model for Magnetic Particle Imaging using realistic magnetic field topologies for algebraic reconstruction}, series = {Inverse Problems}, volume = {36}, journal = {Inverse Problems}, number = {12}, publisher = {IOP Publishing}, doi = {10.1088/1361-6420/abb446}, abstract = {We derive a new 3D model for magnetic particle imaging (MPI) that is able to incorporate realistic magnetic fields in the reconstruction process. In real MPI scanners, the generated magnetic fields have distortions that lead to deformed magnetic low-field volumes with the shapes of ellipsoids or bananas instead of ideal field-free points (FFP) or lines (FFL), respectively. Most of the common model-based reconstruction schemes in MPI use however the idealized assumption of an ideal FFP or FFL topology and, thus, generate artifacts in the reconstruction. Our model-based approach is able to deal with these distortions and can generally be applied to dynamic magnetic fields that are approximately parallel to their velocity field. We show how this new 3D model can be discretized and inverted algebraically in order to recover the magnetic particle concentration. To model and describe the magnetic fields, we use decompositions of the fields in spherical harmonics. We complement the description of the new model with several simulations and experiments, exploring the effects of magnetic fields distortion and reconstruction parameters on the reconstruction.}, language = {en} } @misc{Rauch, type = {Master Thesis}, author = {Rauch, Johannes}, title = {Entwicklung eines Regelverfahrens f{\"u}r einen optimierten und zentralen Blindleistungsabruf zur Beeinflussung des Blindleistungshaushalts von Mittelspannungsnetzen unter Einhaltung von Netzrestriktionen}, doi = {10.35096/othr/pub-659}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-6595}, school = {Ostbayerische Technische Hochschule Regensburg}, pages = {115}, abstract = {Die Energiewende f{\"u}hrt zu neuen Herausforderungen f{\"u}r Verteilungsnetzbetreiber hinsichtlich der Er-bringung von Systemdienstleistungen, der Integration weiterer Erzeugungsanlagen und Lasten sowie der Gew{\"a}hrleistung einer hohen Versorgungssicherheit und normgerechten Spannungsqualit{\"a}t. Die De-ckung der auftretenden Blindleistungsbedarfe seitens der Netzbetriebsmittel, Verbraucher und Erzeu-gungsanlagen gewinnt durch den Wegfall der Großkraftwerke f{\"u}r Netzbetreiber zunehmend an Bedeu-tung. Das Projekt SyNErgie besch{\"a}ftigt sich diesbez{\"u}glich mit der Entwicklung neuartiger Blindleis-tungsmanagementsysteme f{\"u}r Mittelspannungsnetze. Ziel ist es, das bisher ungenutzte, freie Blindleis-tungspotential betrieblicher Kompensationsanlagen und dezentraler Erzeugungsanlagen (allgemein: Blindleistungsquellen) zu nutzen, um die Blindleistungs{\"a}nderungsf{\"a}higkeit eines Verteilungsnetzes zu erh{\"o}hen. Diese Arbeit besch{\"a}ftigt sich mit der Entwicklung eines zentralen Blindleistungsregelsystems, bei dem Blindleistungsquellen auf Basis von „Optimal Power Flow"-Berechnungen {\"u}ber eine zentrale Recheninstanz angesteuert werden. Zum Einsatz kommt dabei ein Optimierungsalgorithmus, der auf Basis des aktuellen Netzzustandes (Spannungs- und Auslastungsreserven) und des aktuellen Blindleis-tungspotentials der Blindleistungsquellen einen bedarfsoptimalen Abruf koordiniert. Das zentrale Re-gelverfahren wird in Netzmodellen verschiedenartiger Mittelspannungsnetzgruppen und unterschiedli-cher Art und Anzahl von Blindleistungsquellen angewendet sowie im Hinblick auf variierende Zielvor-gaben und Randbedingungen evaluiert und diskutiert.}, language = {de} } @misc{Urban, type = {Master Thesis}, author = {Urban, Johannes}, title = {Photoelektrisches Direktladen von Elektrofahrzeugen im Inselbetrieb}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-20285}, school = {Ostbayerische Technische Hochschule Regensburg}, pages = {118}, abstract = {Die Arbeit befasst sich mit der Ladung von Elektrofahrzeugen durch Solarenergie in einem Inselsystem. Diese Art der Ladung entlastet die Netze und hat einen sehr hohen Leistungswirkungsgrad. Es wurde ein Prototyp einer Direkt-ladestation gebaut, welche verschiedene Elektrofahrzeuge mit einem neuartigen Verfahren aufladen kann. Sie enth{\"a}lt einen optionalen Pufferakkumulator und einen Vollbr{\"u}cken-Gegentaktwandler f{\"u}r die Ladung bei schlechter Solarleistung. Ein Teil der Arbeit behandelt ausf{\"u}hrlich die Auslegung, die Komponenten und bisher undokumentiertes Verhalten von Gegentaktwandlern. Des Weiteren wird das Prinzip der Solardirekt-ladung und deren Umsetzung sowie die Umsetzung des Gesamtsystems beschrieben. Es folgt ein Kapitel zur Wirtschaftlichkeit der Solardirektladung mit Handlungsempfehlungen. Insgesamt l{\"a}sst sich schließen, dass Solardirektladung bei nutzungsorientierter Auslegung der Anlage und langer Laufzeit wirtschaftlich ist. This work addresses the charging of electric vehicles with solar power in an off-grid system. Charging this way reduces the stress on the grid and has a very high power efficiency. A prototype of a direct charging station was built which is able to charge several different electric vehicles in a novel way. It includes an optional buffer battery and a full bridge converter for being able to charge electric vehicles at times o flow solar power. One chapter explains in detail the design, the components and so far undocumented properties of full and half bridge converters. The principle and the implementation of direct solar charging and the implementation of the whole system is described. The last chapter covers the cost effectiveness of solar chargin gas well as recommendations. All in all it can be stated that solar direct charging is ecomomically advantageous if it is projected according to the user's demand.}, subject = {Fotovoltaik}, language = {de} } @article{KeimMarxNonnetal., author = {Keim, Vincent and Marx, P. and Nonn, Aida and M{\"u}nstermann, Sebastian}, title = {Fluid-structure-interaction modeling of dynamic fracture propagation in pipelines transporting natural gases and CO2-mixtures}, series = {International Journal of Pressure Vessels and Piping}, volume = {175}, journal = {International Journal of Pressure Vessels and Piping}, number = {August}, publisher = {Elsevier}, doi = {10.1016/j.ijpvp.2019.103934}, abstract = {As part of current design standards, the Battelle Two-Curve Model (BTCM) is still widely used to predict and secure ductile crack arrest in gas transmission pipelines. For modern linepipe steels and rich natural gases or CO2 mixtures, the BTCM might lead to incorrect predictions. On the one hand, it suffers from the insufficient description of the individual physical processes in the pipe material and fluid itself. Furthermore, the model does not account for fluid-structure-interaction (FSI) effects during simultaneous running-ductile fracture (RDF) and mixture decompression. Numerical FSI models allow for a more sophisticated, coupled analysis of the driving forces for the failure of pipelines. This paper deals with the development of an FSI model for the coupled prediction of 3D pressure profiles acting on the inner pipe wall during crack propagation. The coupled Euler-Lagrange (CEL) method is used to link the fluid and structure models. In a Lagrange formulation, the modified Bai-Wierzbicki (MBW) model describes the plastic deformation and ductile fracture as a function of the underlying stress/strain conditions. The fluid behavior is calculated in a 3D model space by Euler equations and the GERG-2008 reference equation of state (EOS). The coupled CEL model is used to predict the RDF in small-diameter pipe sections for different fluid mixtures. The calculated 3D pressure distributions ahead and behind the running crack tip (CT) significantly differ in axial and circumferential directions depending on the mixture composition. The predicted FSI between the pipe wall and fluid decompression in 3D CEL/FSI model provides reliable knowledge about the pressure loading of the pipeline during RDF.}, subject = {Fluid-Struktur-Wechselwirkung}, language = {en} } @inproceedings{SchorrBoehmZentneretal., author = {Schorr, Philipp and B{\"o}hm, Valter and Zentner, Lena and Zimmermann, Klaus}, title = {Dynamical Investigation of Crawling Motion System based on a Multistable Tensegrity Structure}, series = {Proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics : Porto, Portugal, 29.07.2018 - 31.07.2018}, booktitle = {Proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics : Porto, Portugal, 29.07.2018 - 31.07.2018}, publisher = {SCITEPRESS}, isbn = {978-989-758-321-6}, doi = {10.5220/0006852701220130}, pages = {122 -- 130}, abstract = {The basic idea of this article is the utilization of the multistable character of a compliant tensegrity structure to control the direction of motion of a crawling motion system. A crawling motion system basing on a two-dimensional tensegrity structure with multiple stable equilibrium states is considered. This system is in contact with a horizontal plane due to gravity. For a selected harmonic actuation of the system small oscillations around the given equilibrium state of the tensegrity structure occur and the corresponding uniaxial motion of the system is evaluated. A change of the equilibrium state of the tensegrity structure yields to novel configuration of the entire system. Moreover, the motion behavior of the novel configuration is totally different although the actuation strategy is not varied. In particular, the direction of motion changes. Therefore, this approach enables a uniaxial bidirectional crawling motion with a controllable direction of motion using only one actuat or with a selected excitation frequency.}, language = {en} } @article{SchorrBoehmZentneretal., author = {Schorr, Philipp and B{\"o}hm, Valter and Zentner, Lena and Zimmermann, Klaus}, title = {Motion characteristics of a vibration driven mobile tensegrity structure with multiple stable equilibrium states}, series = {Journal of Sound and Vibration}, volume = {437}, journal = {Journal of Sound and Vibration}, number = {December}, publisher = {Elsevier}, doi = {10.1016/j.jsv.2018.09.019}, pages = {198 -- 208}, abstract = {A novel type of a vibration driven motion system based on a compliant tensegrity structure with multiple stable equilibrium states is considered. These equilibrium configurations correspond to different prestress states with different dynamical properties. Therefore, the motion characteristics can be varied by changing the equilibrium state. For the application in the fields of mobile robotics, these discrete adjustable dynamics are advantageous. The vibration modes of the structure as well as the corresponding motion characteristics of the system can be adapted to the given environmental conditions in order to ensure a reliable motion. In this paper, dynamical investigations of an exemplary two-dimensional multistable tensegrity structure are considered. For the chosen parameter values the structure features two relevant equilibrium configurations. The resulting motion system is in contact to a horizontal plane due to gravity and the actuation is realized by the harmonic variation of the length of a single tensioned member. The motion of the system is simulated for various actuation frequencies with the different equilibrium states as an initial configuration. A uniaxial or a planar movement occurs depending on the selection of the actuated member within the tensegrity structure. The steady state motion is evaluated regarding motion characteristics like the steady state velocity. Moreover, the influences on the motion behavior caused by the different equilibrium states as an initial condition are emphasized. (C) 2018 Elsevier Ltd. All rights reserved.}, language = {en} } @inproceedings{BoehmSchorrZimmermannetal., author = {B{\"o}hm, Valter and Schorr, Philipp and Zimmermann, Klaus and Zentner, Lena}, title = {An Approach to the Estimation of the Actuation Parameters for Mobile Tensegrity Robots with Tilting Movement Sequences}, series = {2018 International Conference on Reconfigurable Mechanisms and Robots (ReMAR); 20-22 June 2018; Delft, Netherlands}, booktitle = {2018 International Conference on Reconfigurable Mechanisms and Robots (ReMAR); 20-22 June 2018; Delft, Netherlands}, publisher = {IEEE}, doi = {10.1109/REMAR.2018.8449871}, pages = {1 -- 8}, abstract = {This paper deals with the locomotion by tilting sequences of shape-variable compliant tensegrity structures. The shape of these structures is controlled by manipulating their prestress state. The tensegrity structure is tilting as consequence of a suitable variation of its shape. By multiple repetition of such tilting sequences a motion is generated. Quasi-static considerations for the considered structures are presented in order to estimate the actuation parameters. For a proper number of actuators this quasi-static approach enables an analytical calculation of the actuation parameters of the structure in order to control the geometrical configuration as required. As an example a two-dimensional tensegrity structure which is in contact with a horizontal plane due to gravity is considered. By successive tilting sequences a uniaxial motion results. The excitation of the structure is calculated for a given change of shape with the quasi-static analysis. The according results are compared with transient dynamic simulations. Qualitative conclusions about the motion behavior and the usability of the quasi-static approach are given.}, language = {en} } @inproceedings{CarrilloLiSchorrKaufholdetal., author = {Carrillo Li, Enrique Roberto and Schorr, Philipp and Kaufhold, Tobias and Rodr{\´i}guez Hern{\´a}ndez, Jorge Antonio and Zentner, Lena and Zimmermann, Klaus and B{\"o}hm, Valter}, title = {Kinematic analysis of the rolling locomotion of mobile robots based on tensegrity structures with spatially curved compressed components}, series = {Applicable Solutions in Non-Linear Dynamical Systems; 15th International Conference "Dynamical Systems - Theory and Applications" (DSTA 2019, 2-5 December, 2019, Lodz, Poland}, booktitle = {Applicable Solutions in Non-Linear Dynamical Systems; 15th International Conference "Dynamical Systems - Theory and Applications" (DSTA 2019, 2-5 December, 2019, Lodz, Poland}, editor = {Awrejcewicz, Jan and Ka{\'{z}}mierczak, Markek and Olejnik, Paweł}, publisher = {Wydawnictwo Politechniki Ł{\´o}dzkiej}, address = {Ł{\´o}d{\'{z}}, Polen}, isbn = {978-83-66287-30-3}, pages = {335 -- 344}, abstract = {In this work, a tensegrity structure with spatially curved members is applied as rolling locomotion system. The actuation of the structure allows a variation of the originally cylindrical shape to a conical shape. Moreover, the structure is equipped with internal movable masses to control the position of the center of mass of the structure. To control the locomotion system a reliable actuation strategy is required. Therefore, the kinematics of the system considering the nonholonomic constraints are derived in this paper. Based on the resulting insight in the locomotion behavior a feasible actuation strategy is designed to control the trajectory of the system. To verify this approach kinematic analyses are evaluated numerically. The simulation data confirm the path following due to an appropriate shape change of the tensegrity structure. Thus, this system enables a two-dimensional rolling locomotion. The use of mechanically compliant tensegrity structures in mobile robots is an attractive research topic, due to the possibility to adjust their mechanical properties reversibly during locomotion. In this paper rolling locomotion of mobile robots based on simple tensegrity structures, consisting of three compressed spatially curved members connected to a continuous net of prestressed tensional members, is discussed. Planar locomotion of these robots is induced by the movement of internal masses. The movement direction can be changed by changing the robot's shape between a cylinder and a truncated cone. The paper focuses on the description of the kinematics of these systems with respect to the shape change.}, language = {en} } @inproceedings{NonnParedesKeimetal., author = {Nonn, Aida and Paredes, Marcelo and Keim, Vincent and Wierzbicki, Tomasz}, title = {Comparison of Fracture Models to Quantify the Effects of Material Plasticity on the Ductile Fracture Propagation in Pipelines}, series = {Proceedings of the 2018 12th International Pipeline Conference, Volume 3: Operations, Monitoring, and Maintenance, Materials and Joining, September 24-28, 2018, Calgary, Alberta, Canada}, booktitle = {Proceedings of the 2018 12th International Pipeline Conference, Volume 3: Operations, Monitoring, and Maintenance, Materials and Joining, September 24-28, 2018, Calgary, Alberta, Canada}, doi = {10.1115/IPC2018-78366}, abstract = {Various numerical approaches have been developed in the last years aimed to simulate the ductile fracture propagation in pipelines transporting CO2 or natural gas. However, a reliable quantification of the influence of material plasticity on the fracture resistance is still missing. Therefore, more accurate description of the material plasticity on the ductile fracture propagation is required based on a suitable numerical methodology. In this study, different plasticity and fracture models are compared regarding the ductile fracture propagation in X100 pipeline steel with the objective to quantify the influence of plasticity parameters on the fracture resistance. The plastic behavior of the investigated material is considered by the quadratic yield surface in conjunction with a non-associated quadratic plastic flow potential. The strain hardening can be appropriately described by the mixed Swift-Voce law. The simulations of ductile fracture are conducted by an uncoupled, modified Mohr-Coulomb (MMC) and the micromechanically based Gurson-Tvergaard-Needleman (GTN) models. In contract to the original GTN model, the MMC model is capable of describing ductile failure over wide range of stress states. Thus, ductile fracture resistance can be estimated for various load and fracture scenarios. Both models are used for the simulation of fracture propagation in DWTT and 3D pressurized pipe sections. The results from the present work can serve as a basis for establishing the correlation between plasticity parameters and ductile fracture propagation.}, language = {en} }