TY - BOOK ED - Sterner, Michael ED - Stadler, Ingo T1 - Energiespeicher - Bedarf, Technologien, Integration N2 - Im Kontext der Energiewende sind Energiespeicher ein zentrales technisches, wirtschaftliches und energiepolitisches Thema.Die Autoren dieses kompakten Werkes geben einen umfassenden Uberblick Uber die verschiedenen Aspekte der Energiespeicherung. Sie beschreiben zunachst die Bedeutung von Energiespeichern in der Energieversorgung und definieren ihre Rolle darin. Dann gehen sie auf den Speicherbedarf in der Strom-, Warme- und Kraftstoffversorgung im Kontext der Energiewende ein. Im Hauptteil werden die verschiedenen Speichertechnologien ausfUhrlich vorgestellt sowie ihre Vor- und Nachteile diskutiert. Praktische Anwendungsbeispiele und die Integration von Speichern Uber alle Energiesektoren hinweg runden das Buch ab. Zahlreiche Grafiken und Beispiele veranschaulichen das gesamte Feld der Energiespeicher und sind als Erganzung samt Animationen online in Farbe verfUgbar.Die ZielgruppenDas Lehr- und Fachbuch wendet sich an Ingenieure, Wissenschaftler, Energieplaner und Energiewirtschaftler in Forschung und Industrie sowie an Studierende an Hochschulen und Universitaten in den Bereichen Maschinenbau, Verfahrenstechnik, Elektrotechnik und Energietechnik. KW - Energiespeicher KW - Energietechnik KW - Power-to-Gas KW - Speicherbedarf KW - Speicherintegration KW - Speichermarkt KW - Speichertechnologien KW - Systemintegration Y1 - 2014 SN - 978-3-642-37379-4 U6 - https://doi.org/10.1007/978-3-642-37380-0 PB - Springer CY - Berlin, Heidelberg ER - TY - CHAP A1 - Jentsch, Mareike A1 - Trost, Tobias A1 - Sterner, Michael T1 - Optimal Use of Power-to-Gas Energy Storage Systems in an 85% Renewable Energy Scenario T2 - Energy Procedia N2 - In future energy systems with high shares of fluctuating renewable energy generation, electricity storage will become increasingly important for the utilization of surplus energy. The Power-to-Gas (PtG) technology is one promising option for solving the challenge of long-term electricity storage and is theoretically able to ease situations of grid congestion at the same time. This article presents the perspectives of PtG in an 85% renewable energy scenario for Germany, quantifying an economic optimum for the PtG capacity as well as an optimized spatial PtG deployment. KW - Deutschland KW - Elektrizität KW - Energieproduktion KW - Energiespeicher KW - erneuerbare Energie KW - Langzeitarchivierung KW - Methan KW - optimale Nutzung KW - PtG (Power-to-Gas) Y1 - 2014 U6 - https://doi.org/10.1016/j.egypro.2014.01.180 SN - 1876-6102 VL - 46 SP - 254 EP - 261 PB - Elsevier ER - TY - JOUR A1 - Brückl, Oliver A1 - Haslbeck, Matthias A1 - Portner, Olaf A1 - Hinz, Gerhard T1 - Kostenminimaler Netzanschluss einer 8-MW-PV-Anlage mithilfe regelbarer Ortsnetztransformatoren JF - Energiewirtschaftliche Tagesfragen N2 - Die steigende Anzahl der Erzeugungsanlagen (EZA) in den Verteilnetzen zwingt viele Verteilnetzbetreiber zum kostenintensiven Netzausbau. Dabei sind die EZA gemäß EEG am technisch und wirtschaftlich günstigsten Verknüpfungspunkt anzuschließen. Zur Bestimmung dieses Punktes ist ein Vergleich sinnvoller Netzanschlussvarianten durchzuführen. Regelbare Ortsnetztransformatoren (RONT) erweitern seit Kurzem die Netzanschlussmöglichkeiten, auch auf Mittelspannungsebene. Das Beispiel eines Anschlusses für eine 8-MW-PV-Anlage zeigt, dass der optimale Netzanschluss eine Kombination zwischen RONT, Spannungsblindleistungsregelung, Trennstellenverlagerung und Leitungsverstärkung sein kann. In diesem Fall bemerkenswert ist, dass der RONT-Einsatz die Netzanschlusskosten um rd. 60 % gegenüber einer separaten Anbindung am Umspannwerk reduziert. Die Autoren beschreiben eingangs die Problematik hoher Netzausbaukosten beim Anschluss von Photovoltaik-Flächenanlagen. Das Vorgehen der durchgeführten Netzanalyse im konkreten Fall (Abb.: Grafische Darstellung des südlichen MS-Netzes der Stadtwerke Kehlheim mit angedeuteter Einspeiseleistung) und die 6 analysierten Netzanschlussvarianten werden beschrieben und diskutiert (Abb.: Gegenüberstellung der Investitionen der verschiedenen Netzausbauszenarien). Die oben genannte günstigste Anschlussvariante besteht aus folgender Kombination: Verlegung der vorhandenen Netztrennstelle zwischen zwei 20-kV-Stränge; Verstärkung einer bestehenden Freileitungsstrecke über 1 km; Einsatz von maximal 15RONT sowie Spannungsblindleistungsregelung durch die PV-Flächenanlage. KW - Blindleistungsregelung KW - elektrische Energieverteilung KW - Investitionskosten KW - Kostenanalyse KW - Mittelspannung (elektrisch) KW - Netzanschluss KW - Netztransformator KW - Ortsnetz (Energie) KW - Photovoltaikanlage KW - Szenarioanalyse KW - Wirtschaftlichkeitsrechnung Y1 - 2014 VL - 64 IS - 6 SP - 63 EP - 65 PB - Energiewirtschaft und Technik, Verl.-Ges. CY - Gräfelfing ER - TY - GEN A1 - Haslbeck, Matthias A1 - Brückl, Oliver T1 - Liberalisierung von Systemdienstleistungen T2 - Zukünftige Stromnetze für erneuerbare Energien N2 - Die Liberalisierung der Blindleistung und Schaffung von regionalen nicht ausschreibungspflichtigen Q-Beschaffungsprozessen ermöglicht vor allem künftig erhebliche Kostenreduktionspotenziale. Allerdings ist die Etablierung mit umfangreichen Eingriffen in den heutigen Normen- und Gesetzesrahmen verbunden. Damit diese Potenziale gehoben werden können, bedarf es einerseits der Möglichkeit der Kostenanrechnung im Rahmen der Netznutzungsentgelte, andererseits eines Anreizsystems, sinnvoll und sorgsam mit Q umzugehen. Grundsätzlich ist vorher gründlich zu untersuchen, ob und ab welchem Zeitpunkt die Liberalisierung der Blindleistung zielführend ist und wie im Detail die Liberalisierung der Blindleistung auszugestalten wäre. KW - Blindleistung KW - Deregulierung KW - Energiewende KW - Kostenreduktion KW - Netzmanagement KW - Netz-Management KW - Privatisierung KW - Stromerzeugung KW - Stromversorgung KW - Wettbewerb KW - Wiederaufbau KW - Wirkleistung Y1 - 2014 SN - 978-3-943891-34-8 SP - 170 EP - 175 PB - Ostbayerisches Technologie-Transfer-Institut (OTTI) CY - Regensburg ER - TY - JOUR A1 - Brückl, Oliver A1 - Dalisson, Nils A1 - Strohmayer, Bernhard A1 - Haslbeck, Matthias T1 - Spannungshaltungsmaßnahmen im Verteilungsnetz : Systemvergleich JF - EW : Magazin für die Energie-Wirtschaft N2 - Verteilungsnetzbetreibern stehen mittlerweile viele Maßnahmen zur Behebung des Spannungsbandproblems zur Verfügung. Innovative Konzepte wie der regelbare Ortsnetztransformator werden in vielen Pilotprojekten erprobt. Unklar ist jedoch noch, welche Maßnahmen beziehungsweise Kombinationen langfristig wirtschaftlich am günstigsten sind. Die Ostbayerische Technische Hochschule Regensburg untersucht daher in einem Forschungsprojekt verschiedene Maßnahmen, um sie unter wirtschaftlichen, technischen und energetischen Gesichtspunkten bewerten zu können. Der Beitrag untersucht am Beispiel des Netzmodells eines Dorfnetzes mit zahlreichen Photovoltaikanlagen unterschiedliche Szenarien für 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 günstigste Lösung ist. Es zeichnet sich jedoch ab, dass der RONT in vielen Fällen (abhängig vom Durchdringungsgrad) die günstigste oder zumeist eine günstige Lösung zur Erhöhung der Netzanschlusskapazität darstellt. KW - Blindleistungsregelung KW - dezentrale Stromerzeugung KW - Einspeisung KW - Energienetzplanung KW - Netzmodell KW - Netzstabilität (Energienetz) KW - Ortsnetz (Energie) KW - Photovoltaik KW - Regeltransformator KW - Spannungsregelung KW - Vergleichsuntersuchung Y1 - 2014 UR - https://emagazin.ew-magazin.de/de/profiles/a21024e15cd4/editions/fc50e368dae3fad315dd SN - 1619-5795 VL - 113 IS - 6 SP - 66 EP - 69 PB - VWEW-Energieverl. CY - Frankfurt am Main ER - TY - CHAP A1 - Nonn, Aida A1 - Erdelen-Peppler, Marion A1 - Wessel, Waldemar A1 - Mahn, Denise T1 - How reliable are the current testing procedures for the safety assurance against crack propagation in seamless gas pipelines T2 - 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 N2 - 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. Y1 - 2014 U6 - https://doi.org/10.13140/2.1.3190.6567 ER - TY - CHAP A1 - Karbasian, H. A1 - Groß-Weege, J. A1 - Nonn, Aida A1 - Zimmermann, S. A1 - Kalwa, Christoph T1 - Assessment of collapse resistance of UOE pipes – comparison of full-scale and ring collapse tests T2 - Proceedings of the 10th International Pipeline Conference 2014 (IPC 2014), September 29 - October 3, 2014, Calgary, Alberta, Canada Y1 - 2014 ER - TY - CHAP A1 - Nonn, Aida A1 - Erdelen-Peppler, Marion A1 - Wessel, Waldemar A1 - Harksen, Silke A1 - Mahn, Denise T1 - How to assure fracture-propagation control for seamless gas pipelines? T2 - 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 N2 - 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. Y1 - 2014 U6 - https://doi.org/10.1115/IPC2014-33169 ER - TY - CHAP A1 - Haumer, Anton A1 - Kral, Christian T1 - The New EDrives Library: A Modular Tool for Engineering of Electric Drives T2 - Proceedings of the 10th International Modelica Conference, March 10-12, 2014, Lund, Sweden N2 - Simulation is an indispensable tool for the engineering of systems containing electric drives. Depending on the design phase and the engineering task different levels of modeling details are required: proof of concept; investigation of energy and power consumption; design of control; etc. The new EDrives library provides three levels of abstraction for inverters: quasi static (neglecting electrical transients); averaging (neglecting switching effects) and switching – for serving different demands. The inverters can feed the machine models of the Modelica Standard Library: Modelica.Magnetic.FundamentalWave and the new Modelica.Magnetic.QuasiStatic.FundamentalWave. The EDrives library copes with arbitrary phase numbers and can be easily extended to develop new control algorithms. In this publication the structure of the library and the implemented control principles are presented. Furthermore; examples comparing the three different levels of abstraction are included. KW - control KW - Electric machines and drives KW - multi phase KW - power electronics KW - quasi static KW - switching KW - thermal behavior KW - transient Y1 - 2014 SN - 978-91-7519-380-9 U6 - https://doi.org/10.3384/ecp14096155 SN - 1650-3686 SN - 1650-3740 SP - 155 EP - 163 PB - Linköping University Electronic Press ER - TY - BOOK A1 - Rill, Georg A1 - Schaeffer, Thomas T1 - Grundlagen und Methodik der Mehrkörpersimulation : Vertieft in Matlab-Beispielen, Übungen und Anwendungen N2 - Dieses Lehrbuch vermittelt nicht nur Grundlagen, sondern stellt auch die Methoden der Mehrkörpersimulation anschaulich dar und erläutert an einfachen Beispielen die Vor- und Nachteile bei der praktischen Anwendung. In den Text integrierte Matlab-Skripte und -Funktionen verdeutlichen die einzelnen Methoden und ermöglichen es, Aufwand und Problematik bei der Umsetzung der Theorie innerhalb von Simulationsprogrammen einzuschätzen. Die Modellbildung, die mathematische Beschreibung und die numerische Simulation von Systemen starrer Körper bilden dabei die Schwerpunkte. Konkret behandelte Beispiele sind die Eigendynamik eines Traktors mit gefederter Vorderachse, das Rotorblatt eines Hubschraubers sowie die Vorderachse eines Pkws. Die entsprechenden Matlab-Skripte und Lösungen zu den Übungsaufgaben können auf der Springer-Homepage beim Buch heruntergeladen werden. Der Inhalt Dynamik des starren Körpers - Bewegungsgleichungen - Starre Körper mit elastischen und kinematischen Verbindungselementen - Integrationsverfahren - Rekursiver Algorithmus - Differential-Algebraische Gleichungen - Analyse von Mehrkörpersystemen - Anwendungs- und Übungsbeispiele aus der Technik Die Zielgruppen Studenten des Maschinenbaus, der Elektrotechnik und Mechatronik sowie der Biomechanik an Hochschulen und Universitäten Ingenieure in der Praxis, die sich mit Fragestellungen der Mehrkörpersimulation (MKS) befassen Entwickler aus der Kfz-Technik sowie Fachleute aus F+E Die Autoren Dr.-Ing. Georg Rill ist Professor mit den Lehrgebieten Technische Mechanik, Ingenieurinformatik, Fahrdynamik, Mehrkörperdynamik sowie Laborleiter Fahrdynamik. Dr.-Ing. Thomas Schaeffer ist Professor mit den Lehrgebieten Konstruktion, CAD, Maschinenelemente und Getriebetechnik, Mehrkörpersysteme und Bewegungstechnik sowie Laborleiter Mehrkörpersimulation, beide an der Ostbayerischen Technischen Hochschule (OTH) Regensburg. Y1 - 2014 U6 - https://doi.org/10.1007/978-3-658-06084-8 PB - Springer CY - Berlin ER - TY - JOUR A1 - Küpper, Carsten A1 - Artmann, Christina A1 - Pischinger, Stefan A1 - Rabl, Hans-Peter T1 - Lube-Oil Dilution of Gasoline Direct-Injection Engines with Ethanol Fuels JF - MTZ worldwide KW - Fuel Ethanol KW - Engine Cold Start KW - Cold Ambient Conditions KW - Fuel Vapor Mass KW - Test Bench Investigations Y1 - 2013 U6 - https://doi.org/10.1007/s38313-013-0090-8 VL - 74 IS - 9 SP - 64 EP - 69 PB - Springer CY - Berlin ER - TY - JOUR A1 - Küpper, Carsten A1 - Artmann, Christina A1 - Pischinger, Stefan A1 - Rabl, Hans-Peter T1 - Schmierölverdünnung von direkteinspritzenden Ottomotoren unter Kaltstartrandbedingungen JF - MTZ - Motortechnische Zeitschrift Y1 - 2013 U6 - https://doi.org/10.1007/s35146-013-0208-1 VL - 74 IS - 9 SP - 710 EP - 715 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Analysis of dynamic ductile fracture propagation in pipeline steels BT - a damage mechanics approach T2 - 6th Pipeline Technology Conference (2013), Ostend, Belgium N2 - 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. Y1 - 2013 U6 - https://doi.org/10.13140/2.1.4370.3046 ER - TY - CHAP A1 - Völling, Alexander A1 - Nonn, Aida A1 - Schneider, Ingo T1 - Anwendung des Kohäsivzonenmodells zur Abbildung von duktilem dynamischen Rissfortschritt in Gasfernleitungen T2 - 45. Tagung des AK Bruch, Berlin, Germany KW - Ferngasleitung KW - Rissfortschritt Y1 - 2013 SP - 253 EP - 262 ER - TY - CHAP A1 - Nonn, Aida A1 - Wessel, Waldemar A1 - Schmidt, Tanja T1 - Application of finite element analysis for assessment of fracture behavior of modern high toughness seamless pipeline steels T2 - 23rd International Society of Offshore and Polar Engineering 2013 (ISOPE 2013), Anchorage, USA N2 - 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. KW - Rissfortschritt KW - Nahtloses Rohr KW - Pipeline KW - Bruchmechanische Prüfung KW - Finite-Elemente-Methode Y1 - 2013 U6 - https://doi.org/10.13140/2.1.4239.2322 ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Application of damage mechanics approach for crack propagation in pipeline T2 - 19th Biennial Joint Technical Meeting (JTM) on Pipeline Research, April 29 - May 3, 2013, Sydney, Australia Y1 - 2013 ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Application of probabilistic fracture mechanics for safety assessment of longitudinally welded linepipes T2 - 6th Pipeline Technology Conference (2013), Ostend, Belgium Y1 - 2013 ER - TY - THES A1 - Urban, Johannes T1 - Photoelektrisches Direktladen von Elektrofahrzeugen im Inselbetrieb N2 - 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 enthält einen optionalen Pufferakkumulator und einen Vollbrücken-Gegentaktwandler für die Ladung bei schlechter Solarleistung. Ein Teil der Arbeit behandelt ausführlich 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 lässt 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. KW - Fotovoltaik KW - Stromtankstelle KW - Elektrofahrzeug KW - Pufferspeicher KW - Photovoltaik KW - Ladestation KW - Elektrofahrzeug KW - Pufferspeicher KW - Vollbrückenwandler Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-20285 ER - TY - JOUR A1 - Freni, Angelo A1 - Frazzica, Andrea A1 - Dawoud, Belal A1 - Chmielewski, Stefanie A1 - Calabrese, Luigi A1 - Bonaccorsi, Lucio Maria T1 - Adsorbent coatings for heat pumping applications: Verification of hydrothermal and mechanical stabilities JF - Applied Thermal Engineering N2 - This paper presents novel experimental methods for verification of both hydrothermal and mechanical stabilities of adsorbent coatings. Experiments have been carried out on zeolite-based coatings over aluminum substrates, prepared by a dip-coating technique developed at CNR-ITAE. Hydrothermal aging of several adsorbent coatings is ongoing. Adsorption and structural stability of some samples under test was successfully verified after 35000 aging cycles by isobars measurement and XRD analysis. Mechanical properties of coatings have been evaluated by applying different typologies of static and dynamic mechanical stresses. Results obtained have been compared with those achieved by subjecting adsorbent coatings prepared by Mitsubishi Plastic Incorporation (MPI) to the same characterization protocol. The comparison between the two types of coating returned that MPI coatings posses similar thermal stability and better mechanical strength than CNR-ITAE coatings. KW - Adsorbent coating KW - Adsorption heat pump KW - Hydrothermal stability KW - Mechanical stability Y1 - 2013 U6 - https://doi.org/10.1016/j.applthermaleng.2011.07.010 VL - 50 IS - 2 SP - 1658 EP - 1663 PB - Elsevier ER - TY - JOUR A1 - Dawoud, Belal T1 - Water vapor adsorption kinetics on small and full scale zeolite coated adsorbers; A comparison JF - Applied thermal engineering N2 - A possibility to enhance both heat and mass transfer characteristics of an adsorber heat exchanger is to apply the adsorbent directly to its surface in form of a consolidated layer. As the majority of the available publications on the effect of both coating technology and adsorbent layer thickness on the adsorption kinetics deals with small scale adsorbent samples, the results obtained can only represent the best case design of an adsorber heat exchanger. This article presents, therefore, a comparison between the adsorption kinetics of water vapour on small as well as two different full scale coated adsorber heat exchanger types with AQSOA-Z02 layers of Mitsubishi Plastics Incorporation under quasi isobaric conditions of adsorption heat pumps. The small scale coated samples have a zeolite dry mass of 200 mg and layer thicknesses of 200, 300 and 500 μm while the full scale adsorbers have a coated zeolite mass between 1.5 and 2.5 kg and layer thicknesses of 150, 200, 300, 400 and 500 μm. In the investigated adsorption heat pump module, up to 52.7 and 57.3% of the equilibrium differential water loading measured with the small scale coated substrates have been obtained after an adsorption-evaporation times of 300 and 600 s, respectively. KW - Adsorbent coating KW - Adsorption heat pump KW - Adsorption kinetics KW - AQSOA-Z02 Y1 - 2013 U6 - https://doi.org/10.1016/j.applthermaleng.2011.07.013 VL - 50 IS - 2 SP - 1645 EP - 1651 PB - Elsevier ER - TY - CHAP A1 - Zenger, Gerhard A1 - Kenner, Susanne A1 - Volbert, Klaus A1 - Waas, Thomas A1 - Kucera, Markus T1 - Acquiring energy data from a medium-voltage grid for future smart grid solutions: A practical smart grid application example realized by use of cellular communication networks of the 2nd and 3rd generation T2 - Proceedings of the 11th Workshop on Intelligent Solutions in Embedded Systems (WISES), 10-11 Sept. 2013, Pilsen, Czech Republic N2 - In this paper we present a practical example of the use of Cellular Communication standards like GPRS and UMTS in a Smart Grid Application. For a more detailed view we demonstrate a possible implementation of Cellular Communication Technologies in a data acquisition application for the collection of energy indicators in a medium-voltage grid. Furthermore, we show a technical overview of relevant and common mobile communication standards available in Germany. The included theoretical examples, Smart Grid scenarios, presented data and results are based on a research project for intelligent power regulation in medium-voltage grids performed in Regensburg (Germany). It is a joint project' of the University of Applied Sciences Regensburg together with a local energy provider and a manufacturer for distribution network systems. KW - Mobile communication KW - Medium voltage KW - Standards KW - Smart grids KW - Feeds KW - Ground penetrating radar Y1 - 2013 UR - https://ieeexplore.ieee.org/document/6664954 SN - 978-3-00-042899-9 SP - 1 EP - 8 PB - IEEE ER - TY - CHAP A1 - Miedl, Christian A1 - Braun, Jürgen T1 - Powertrain and electric system design of a 800-volt all-electric car T2 - European Conference on Nanoelectronics and Embedded Systems for Electric Mobility, eMotion in Smart Cities, 24.-28. September, 2012, Bologna, Italy Y1 - 2012 ER - TY - JOUR A1 - Haumer, Anton A1 - Kral, Christian A1 - Vukovic, Vladimir A1 - David, Alexander A1 - Hettfleisch, Christian A1 - Huzsvar, Attila T1 - A Parametrization Scheme for High Performance Thermal Models of Electric Machines using Modelica JF - IFAC Proceedings Volumes N2 - 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. KW - Electric machines KW - Induction machines KW - Thermal models KW - Model reduction KW - Parameter identification KW - Parameter optimization Y1 - 2012 U6 - https://doi.org/10.3182/20120215-3-AT-3016.00187 SN - 1474-6670 VL - 45 IS - 2 SP - 1058 EP - 1062 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Bogomolov, Maxim A1 - Kral, Christian A1 - Haumer, Anton A1 - Lomonova, Elena T1 - Modeling of permanent magnet synchronous machine with fractional slot windings T2 - 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 N2 - 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. KW - Concentrated KW - fractional slot KW - harmonics KW - Modelica KW - permanent magnet KW - subharmonics KW - synchronous machines KW - Torque KW - windings Y1 - 2012 SN - 978-1-4673-2421-2 SN - 978-1-4673-2419-9 SN - 978-1-4673-2420-5 U6 - https://doi.org/10.1109/IECON.2012.6388912 SN - 1553-572X SP - 1894 EP - 1899 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Haumer, Anton A1 - Kral, Christian ED - Otter, Martin ED - Zimmer, Dirk T1 - Motor Management of Permanent Magnet Synchronous Machines T2 - Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany N2 - 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. KW - Field Oriented Control KW - Optimization of Field Current KW - permanent magnet synchronous machine Y1 - 2012 SN - 978-91-7519-826-2 U6 - https://doi.org/10.3384/ecp12076159 SN - 1650-3686 SN - 1650-3740 SP - 159 EP - 166 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Bogomolov, Maxim A1 - Lomonova, Elena T1 - Harmonic wave model of a permanent magnet synchronous machine for modeling partial demagnetization under short circuit conditions T2 - 2012 XXth International Conference on Electrical Machines (ICEM 2012) ; Marseille, France, 2 - 5 September 2012 N2 - 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. KW - demagnetization KW - harmonic analysis KW - magnetic fields KW - magnetic flux KW - magnetic potential difference KW - permanent magnet synchronous machine KW - reluctance KW - segmentation KW - temperature Y1 - 2012 SN - 978-1-4673-0142-8 U6 - https://doi.org/10.1109/ICElMach.2012.6349880 SP - 295 EP - 301 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Lee, Sang Bin T1 - Robust thermal model for the estimation of rotor cage and stator winding temperatures of induction machines T2 - 2012 XXth International Conference on Electrical Machines ; Marseille, France, 02.- 05.09.2012 N2 - 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. KW - asynchronous machines KW - Cooling KW - dynamic load KW - equivalent circuits KW - lumped element thermal equivalent circuit model KW - Rotors KW - squirrel cage induction machine KW - stators KW - temperature estimation Y1 - 2012 SN - 978-1-4673-0142-8 SN - 978-1-4673-0143-5 SN - 978-1-4673-0141-1 U6 - https://doi.org/10.1109/ICElMach.2012.6350127 SP - 1810 EP - 1816 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Lee, Sang Bin T1 - Innovative thermal model for the estimation of permanent magnet and stator winding temperatures T2 - 2012 IEEE Energy Conversion Congress and Exposition (ECCE 2012) ; Raleigh, NC, USA 15.09.-20.09.2012 N2 - 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. KW - Cooling KW - dynamic load KW - lumped element thermal equivalent circuit model KW - permanent magnet machines KW - permanent magnet synchronous machine KW - stators KW - synchronous machines KW - temperature estimation KW - temperature sensors KW - variable speed Y1 - 2012 SN - 978-1-4673-0803-8 SN - 978-1-4673-0802-1 SN - 978-1-4673-0801-4 U6 - https://doi.org/10.1109/ECCE.2012.6342386 SN - 2329-3721 SN - 2329-3748 SP - 2704 EP - 2711 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Brückl, Oliver A1 - Krpal, Ondrej A1 - Riepl, Markus T1 - Influence of wind and solar energy on the frequency of switching operations of On-Load Tap-Changers (OLTC) BT - Electric Power Engineering T2 - Proceedings of the 13th International Scientific Conference Electric Power Engineering 2012, EPE 2012; Vol. 2 Y1 - 2012 SP - 719 EP - 722 PB - EPE CY - Brno, Czech Republic ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Simulation of ductile crack propagation in high-strength pipeline steel using damage models T2 - 9th International Pipeline Conference 2012 (IPC 2012), Calgary, Canada N2 - 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. Y1 - 2012 U6 - https://doi.org/10.1115/IPC2012-90653 ER - TY - CHAP A1 - Kofiani, Kirki A1 - Nonn, Aida A1 - Wierzbicki, Tomasz A1 - Kalwa, Christoph A1 - Walters, Carey T1 - Experiments and fracture modeling of high-strength pipelines for high and low stress triaxiality T2 - 22nd International Society of Offshore and Polar Engineering 2012 (ISOPE 2012), Rhodes, Greece, June 2012 N2 - 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. Y1 - 2012 ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - Failure modeling of pipeline X100 Material in temperature transition region T2 - 22nd International Society of Offshore and Polar Engineering 2012 (ISOPE 2012), Rhodes, Greece N2 - 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. Y1 - 2012 ER - TY - JOUR A1 - Ostermeier, Daniel A1 - Mottok, Jürgen A1 - Knorr, Christine A1 - Huber, Michael ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - Competence Atlas for Save and Green Road Vehicles in the Electro Mobility Cluster Regensburg JF - Applied Research Conference 2012 (ARC 2012) 25./26. June 2012, Nuremberg Y1 - 2012 SP - 86 EP - 92 ER - TY - CHAP A1 - Mottok, Jürgen T1 - Migration path for secure and economic smart power grid devices with transitional smart metering support T2 - 2nd Applied Research Conference 2012 (ARC 2012), 25./26. June 2012, Nuremberg Y1 - 2012 SP - 64 EP - 70 ER - TY - CHAP A1 - Nick, Matthias A1 - Schorer, Michael A1 - Mottok, Jürgen ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - Feasibility Study of a Build System Performing Automated Builds Based on Model-Based Build Descriptions T2 - 2nd Applied Research Conference 2012 (ARC 2012), 25./26. June 2012, Nuremberg Y1 - 2012 SP - 71 EP - 75 PB - Shaker CY - Aachen ER - TY - RPRT ED - Neuleitner, Nikolaus ED - Steffens, Oliver T1 - Energienutzungsplan für die Gemeinde Sinzing BT - Phase I. Bestandsaufnahme. Ergebnisbericht 1 (12/2011) Y1 - 2011 ER - TY - CHAP A1 - Bäuml, T. A1 - Haumer, Anton A1 - Kapeller, H. A1 - Starzinger, J. A1 - Farzi, P. T1 - Impact of inverter pulse inhibition on the high-voltage supply system of an electric vehicle — A simulative approach T2 - 2011 IEEE Vehicle Power and Propulsion Conference (VPPC 2011) : Powering sustainable transportation ; Chicago, Illinois, USA, 06. - 09.09.2011 N2 - 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. KW - asynchronous machines KW - Connectors KW - electric vehicles KW - Inverters KW - invertors KW - Mathematical model KW - Object oriented modeling KW - permanent magnet machines KW - power engineering computing KW - Rotors KW - synchronous machines KW - Torque KW - Vehicles Y1 - 2011 SN - 978-1-61284-248-6 SN - 978-1-61284-247-9 SN - 978-1-61284-246-2 U6 - https://doi.org/10.1109/VPPC.2011.6043159 SP - 1 EP - 5 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Hong, Jongman A1 - Hyun, Doosoo A1 - Kang, Tae-june A1 - Lee, Sang Bin A1 - Kral, Christian A1 - Haumer, Anton T1 - Detection and classification of rotor demagnetization and eccentricity faults for PM synchronous motors T2 - 2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011) : Energy conversion innovation for a clean energy future ; Phoenix, Arizona, USA, 17.-22.09.2011 N2 - 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. KW - AC Machine KW - Condition Monitoring KW - d-axis Inductance KW - Demagnetization KW - Eccentricity KW - fault diagnosis KW - invertors KW - Magnetic Saturation KW - Permanent Magnet (PM) KW - permanent magnet motors KW - Synchronous Motor (SM) KW - synchronous motors Y1 - 2011 SN - 978-1-4577-0542-7 SN - 978-1-4577-0541-0 SN - 978-1-4577-0540-3 U6 - https://doi.org/10.1109/ECCE.2011.6064103 SN - 2329-3721 SN - 2329-3748 SP - 2512 EP - 2519 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Hong, Jongman A1 - Lee, Sang Bin A1 - Kral, Christian A1 - Haumer, Anton T1 - Detection of airgap eccentricity for permanent magnet synchronous motors based on the d-axis inductance T2 - 8th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics & Drives (SDEMPED), 2011 // 05. - 08.09.2011, Bologna, Italy N2 - 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. KW - Airgap Eccentricity KW - Condition Monitoring KW - Diagnostics KW - fault location KW - inductance KW - load (electric) KW - machine testing KW - Magnetic Saturation KW - Motor Current Signature Analysis (MCSA) KW - permanent magnet motors KW - Permanent Magnet Synchronous Motor KW - synchronous motor protection Y1 - 2011 SN - 978-1-4244-9301-2 SN - 978-1-4244-9303-6 U6 - https://doi.org/10.1109/DEMPED.2011.6063651 SP - 378 EP - 384 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Haumer, Anton A1 - Kral, Christian T1 - Modeling a Mains connected PWM Converter with Voltage-Oriented Control T2 - Proceedings of the 8th International Modelica Conference, Technical Univeristy, Dresden, Germany, 20.-22.03.2011 N2 - 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. KW - Active Front-End KW - PWM Converter KW - Voltage-Oriented Control Y1 - 2011 U6 - https://doi.org/10.3384/ecp11063388 SP - 388 EP - 397 PB - Linköping University Electronic Press ER - TY - CHAP A1 - Jungreuthmayer, C. A1 - Bauml, T. A1 - Winter, O. A1 - Ganchev, M. A1 - Kapeller, H. A1 - Haumer, Anton A1 - Kral, Christian T1 - Heat and fluid flow analysis of an internal permanent magnet synchronous machine by means of computational fluid dynamics T2 - 2011 IEEE International Electric Machines & Drives Conference (IEMDC 2011) ; Niagara Falls, Ontario, Canada, 15 - 18 May 2011 N2 - 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. KW - CFD KW - computational fluid dynamics KW - Cooling KW - finite element analysis KW - interior magnet KW - permanent magnet machines KW - permanent magnet synchronous machine KW - Rotors KW - sensor placement KW - stators KW - synchronous machines KW - temperature KW - temperature distribution KW - thermal analysis Y1 - 2011 SN - 978-1-4577-0060-6 SN - 978-1-4577-0061-3 SN - 978-1-4577-0059-0 U6 - https://doi.org/10.1109/IEMDC.2011.5994651 SP - 515 EP - 520 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton T1 - The New FundamentalWave Library for Modeling Rotating Electrical Three Phase Machines T2 - Proceedings of the 8th International Modelica Conference; March 20th-22nd; Technical Univeristy; Dresden; Germany N2 - 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. KW - fundamental wave KW - Modelica Standard Library MSL KW - Rotating electrical three phase machines KW - time transients Y1 - 2011 SN - 978-91-7393-096-3 U6 - https://doi.org/10.3384/ecp11063170 SN - 1650-3686 SN - 1650-3740 SP - 170 EP - 179 PB - University Electronic Press CY - Linköping ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton ED - Schmidt, Matthias T1 - Object Oriented Modeling of Rotating Electrical Machines T2 - Advances in Computer Science and Engineering Y1 - 2011 SN - 978-953-307-173-2 SN - 978-953-51-5990-2 U6 - https://doi.org/10.5772/15898 SP - 135 EP - 160 PB - IntechOpen ER - TY - CHAP A1 - Nonn, Aida A1 - Kalwa, Christoph T1 - The effect of microstructure, strain hardening and strain rate on the fracture behavior of high strength pipeline steels T2 - 2nd International Conference on Material Modelling (ICMM2), 31th August - 2nd September, 2011 at Mines Paris Tech, France Y1 - 2011 ER - TY - RPRT A1 - Michael Sterner, A1 - Mareike Jentsch, A1 - Uwe Holzhammer, T1 - Energiewirtschaftliche und ökologische Bewertung eines Windgas-Angebotes N2 - In this technical report, (1) the benefits of the new technology for future energy supply are discussed, (2) the climate protection effect of wind gas is discussed, and (3) a reasonable use of wind energy for gas generation is analyzed. In particular, windgas in the heat market is discussed in the utilization cascade of wind energy. The new "power-to-gas" concept opens up completely new possibilities for the integration of renewable energies and for coupling the electricity and gas grids. The Sabatier process, which has been known for 100 years, was first developed for this purpose in 2008 under the leadership of the Center for Solar Energy and Hydrogen Research and Fraunhofer IWES (formerly ISET) with electrolysis to create the "power-to-gas" concept for energy storage. A first pilot plant was built by ZSW Stuttgart on behalf of SolarFuel in 2009. This plant proves the technical feasibility of the new technology. Renewable gas is stored, transported and used as required as control and reserve energy via reconversion, e.g. in combined cycle power plants. In this way, decentrally generated renewable electricity is converted into a CO2 -neutral energy carrier with high energy density. The key advantage of renewable methane is the use of existing infrastructure such as gas grids, gas storage and end-use equipment for the integration of renewable energy. Technologies for natural gas are state of the art and commercially available. Methane also has three times the energy density of hydrogen. T2 - Energy-economic and ecological evaluation of a windgas offer (Power-to-Gas) Y1 - 2011 U6 - https://doi.org/10.13140/RG.2.2.25093.68328 PB - Fraunhofer Institute for Energy Economics and Energy System Technology CY - Kassel ER - TY - JOUR A1 - Kral, Christian A1 - Kapeller, Hansjörg A1 - Gragger, Johannes V. A1 - Haumer, Anton A1 - Kubicek, Bernhard T1 - Phenomenon Rotor Fault-Multiple Electrical Rotor Asymmetries in Induction Machines JF - IEEE Transactions on Power Electronics N2 - 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. KW - asynchronous machines KW - Electrical rotor asymmetries KW - induction machine KW - rotor fault KW - Rotors KW - simulation model KW - skewing Y1 - 2010 U6 - https://doi.org/10.1109/TPEL.2009.2037502 SN - 0885-8993 SN - 1941-0107 VL - 25 IS - 5 SP - 1124 EP - 1134 PB - IEEE ER - TY - CHAP A1 - Kapeller, Hansjörg A1 - Haumer, Anton A1 - Kral, Christian A1 - Grabner, Christian ED - Ao, Sio-Iong ED - Gelman, Len T1 - Different Designs of Large Chipper Drives T2 - Electronic Engineering and Computing Technology N2 - 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. KW - induction motor KW - load impulses KW - slip ring KW - speed control KW - squirrel cage Y1 - 2010 SN - 978-90-481-8775-1 SN - 978-90-481-8776-8 U6 - https://doi.org/10.1007/978-90-481-8776-8_9 SP - 93 EP - 104 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Grabner, Christian ED - Ao, Sio-Iong ED - Gelman, Len T1 - Determination of Consistent Induction Motor Parameters T2 - Electronic Engineering and Computing Technology N2 - 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. KW - consistent parameters KW - iduction motor KW - partial load efficiency Y1 - 2010 SN - 978-90-481-8775-1 SN - 978-90-481-8776-8 U6 - https://doi.org/10.1007/978-90-481-8776-8_7 VL - 60 SP - 71 EP - 80 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Grabner, Christian ED - Ao, Sio-Iong ED - Gelman, Len T1 - Broken Rotor Bars in Squirrel Cage Induction Machines – Modeling and Simulation T2 - Electronic Engineering and Computing Technology N2 - 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. KW - broken rotor bar KW - induction machines KW - Modelica KW - rotor asymmetries KW - squirrel cage Y1 - 2010 SN - 978-90-481-8775-1 SN - 978-90-481-8776-8 U6 - https://doi.org/10.1007/978-90-481-8776-8_8 SP - 81 EP - 91 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Gragger, Johannes V. A1 - Haumer, Anton A1 - Einhorn, Markus T1 - Averaged Model of a Buck Converter for Efficiency Analysis JF - Engineering Letters N2 - In this work a buck converter model for multidomain simulations is proposed and compared with a state-of-the-art buck converter model. In the proposed model no switching events are calculated. By avoiding the computation of the switching events in power electronic models the processing time of multidomain simulations can be decreased significantly. The proposed model calculates any operation point of the buck converter in continuous inductor current conduction mode (CICM) while considering the conduction losses and switching losses. It is possible to utilize the proposed modeling approach also for other dc-to-dc converter topologies. Laboratory test results for the validation of the proposed model are included. Y1 - 2010 UR - https://www.researchgate.net/profile/Markus-Einhorn/publication/41668038_Averaged_Model_of_a_Buck_Converter_for_Efficiency_Analysis/links/55100b490cf21287416cb105/Averaged-Model-of-a-Buck-Converter-for-Efficiency-Analysis.pdf VL - 18 CY - Hong Kong ER -