TY - GEN A1 - Sterner, Michael T1 - The role of green H 2 + Power-to-X in the German Energy Transition T2 - First Brazilian-German Green Hydrogen Congress, Brasilia 06.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Wasserstoff KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Die Grenzen des Wasserstoff-Hypes T2 - 1. Mitteldeutscher Wasserstoffkongress, 2. November 2021, Leuna CCE Kulturhaus KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Wasserstoff Y1 - 2021 ER - TY - CHAP A1 - Altmann, Robert A1 - Gebhard, Jürgen A1 - Troeger, Adrian A1 - Winkler, Markus A1 - Töpfer, Georg A1 - Remmele, Edgar A1 - Gaderer, Matthias A1 - Rabl, Hans-Peter ED - Berns, Karsten ED - Dressler, Klaus ED - Kalmar, Ralf ED - Stephan, Nicole ED - Teutsch, Roman ED - Thul, Martin T1 - Engine performance and emission analysis of a NRMM CI engine with common rail injection system operated with diesel fuel and rapeseed oil fuel T2 - Proceedings of the 6th Commercial Vehicle Technology Symposium 2020/2021 N2 - The use of alternative fuels in high-power non-road mobile machinery (NRMM) combustion engines is a possible way to substitute fossil fuel. By using pure vegetable oil fuels, like rapeseed oil fuel (DIN 51605), the greenhouse gases can be reduced effectively. Due to the differences in physical and chemical properties, a modification of the engine control unit calibration is necessary to adapt the working process on the fuel. Without modifications, the engine power output with rapeseed oil fuel is lower than with diesel fuel because of the smaller energy content. By adapting the engine settings, like the injection fuel mass, the power loss can be compensated but it accompanies with a higher fuel consumption. The engine emissions at part load conditions show, that there are benefits in particle emissions by using rapeseed oil at similar NOx emissions. Therefore, a design of experiment setup was initiated on a selected engine operation point to determine the effects of further parameters, like rail pressure, manifold pressure and injection pattern, on the process and to see the potential of an optimized calibration. KW - CI engine KW - common rail injection KW - Diesel Engine KW - DoE KW - rapeseed oil Y1 - 2021 SN - 978-3-658-29716-9 U6 - https://doi.org/10.1007/978-3-658-29717-6_16 SP - 231 EP - 242 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Buttner, Johannes A1 - Alonso-Villa, Cristina A1 - Bohigas Boladeras, Pere A1 - Kucera, Markus A1 - Waas, Thomas T1 - The Need for New Software Architectures for Next-generation Vehicle T2 - Proceedings of the 5th International E-Conference on Advances in Engineering, Technology and Management (ICETM 2021) N2 - Assuming that future connected cars with automated driving functions will require even more computing power and communication bandwidth, the current network infrastructure as well as the existing individualized control units are not a profitable option for such vehicles. In addition, changing user expectations demand flexible architectural patterns and upgradeability of software components without the need to visit the workshop. However, the current statically developed and configured ECU architecture does not offer any practicable possibilities for this. For these reasons, the research for a new dynamic and flexible architecture is necessary. This new type of system architecture is expected to meet future requirements in terms of space, cost, performance, energy efficiency and number of required computing units in the vehicle, which will arise as a result of the implementation/inclusion of new automated driving functionalities, and due to the changes in user expectations. Solutions to this issue can be found in the field of enterprise IT (cluster computing), in which technologies such as Ethernet, container-based virtualization and flexible software architectures have proven themselves to be very efficient for years. Relevant infrastructures, for example from cloud computing providers, have commonly been used in high-performance or high-availability applications. Thus, in the research project A 3F has been investigated which of these concepts and methods can be applied to modern vehicle system architectures. One of the main goals is to assess the synergy potential of the two sectors, information technology and automotive industry, which to date have very different orientations. However, this synergy is expected to grow strongly in the course of the developments mentioned above. In the following pages, the necessary changes related to hardware and software will be discussed briefly und will be compared to concepts and possible solutions from the IT world. Y1 - 2021 UR - https://www.seekdl.org/conferences/paper/details/10605.html SN - 978-1-63248-192-4 SP - 58 EP - 61 ER - TY - CHAP A1 - Mühlbauer, Christian A1 - Rabl, Hans-Peter A1 - Rottengruber, Hermann T1 - Akustische Optimierung von mechatronischen Direkteinspritzsystemen und Analyse der Auswirkungen auf die Robustheit im Systembetrieb T2 - Motor- und Aggregate-Akustik: 11. Magdeburger Symposium, Tagungsband N2 - The tightening of the emission legislation and political and social demands for sustainable mobility are forcing the automotive industry to develop complex, high precision mechatronic drive systems. The increasing precision of mechatronic components generally leads to an increase in structural excitation and thus to a rise in noise. The socalled ticking of the fuel injection system has a rather low sound pressure level compared to the residual engine noise. Nevertheless, the impulsive and high frequency noise character leads to a decline concerning the perception of comfort and sound quality. In order to identify the sound quality of fuel injection systems as a frontloading measure, a system test bench has been developed which represents the structureborne and airborne sound radiation of the stand-alone injection system in a close to series configuration. In this paper, measures for the acoustic optimization of injection systems and their effects on the robustness of the system are discussed. The focus is on engine idling, since at this operating point the ticking of the injectors and the high-pressure pump can be perceived most clearly due to the low masking effects of other noise sources. For this purpose, the injection parameters were measured during full engine operation and transferred to the system test bench. By using a special development control unit, it was possible to modify the parameters, quantify their influence on the acoustic behavior and, based on this, define NVH optimized control strategies. For the robustness evaluation of the NVH optimized control strategies, key functions of the injection system were analyzed under varying boundary conditions in system operation on an injection rate test bench. N2 - Die Verschärfung der Abgasgesetzgebung sowie die politischen und gesellschaftlichen Forderungen an eine nachhaltige Mobilität zwingen die Automobilindustrie zur Entwicklung komplexer, hochpräziser mechatronischer Antriebssysteme. Die zunehmende Präzision der mechatronischen Komponenten führt dabei in der Regel zu einer Zunahme der Strukturanregung und damit zu einer Erhöhung der Störgeräusche. Das so genannte Tickern des Kraftstoffeinspritzsystems hat im Vergleich zum Restmotorgeräusch einen niedrigeren Schalldruckpegel. Dennoch führt der impulshaltige und hochfrequente Geräuschcharakter zu einem Mangel in der Komfort- und Qualitäts- 32 wahrnehmung. Um die Geräuschqualität von raftstoffeinspritzsystemen als Frontloading-Maßnahme zu identifizieren, wurde ein Systemprüfstand entwickelt, der die Körper- und Luftschallabstrahlung des Einspritzsystems in seriennaher Konfiguration abbildet. In diesem Beitrag werden Maßnahmen zur akustischen Optimierung von Einspritzsystemen und deren Auswirkungen auf die Robustheit im Systembetrieb diskutiert. Der Fokus liegt dabei auf dem Motorleerlauf, da an diesem Betriebspunkt das Tickern der Injektoren und der Hochdruckpumpe durch den geringen Maskierungseffekt anderer Geräusche am deutlichsten wahrzunehmen ist. Dazu wurden die Einspritzparameter im Vollmotorbetrieb erfasst und auf den Systemprüfstand transferiert. Durch ein spezielles Entwicklungssteuergerät war es möglich, die Parameter zu modifizieren, deren Einfluss auf das akustische Verhalten zu quantifizieren und darauf aufbauend NVHoptimierte Ansteuerstrategien zu definieren. Zur Robustheitsbewertung der NVHoptimierten Ansteuerstrategien wurden Schlüsselfunktionen des Einspritzsystems unter variierenden Randbedingungen im Systembetrieb analysiert. Y1 - 2021 U6 - https://doi.org/10.25673/36611 VL - 11 SP - 32 EP - 51 PB - Otto-von-Guericke-Universität CY - Magdeburg ER - TY - CHAP A1 - Schneider, Sebastian A1 - Mühlbauer, Christian A1 - Sittl, Christopher A1 - Rottengruber, Hermann A1 - Rabl, Hans-Peter A1 - Wagner, Marcus A1 - Verhey, Jesko L. ED - Rottengruber, Hermann ED - Luft, Tommy ED - Schneider, Sebastian T1 - Tickergeräuschanalyse an einem Otto-DI-Motor mittels empirischer Bewertungsformel T2 - Motor- und Aggregate-Akustik: 11. Magdeburger Symposium, Tagungsband N2 - Beim Kauf eines Pkw wird der akustische Qualitätseindruck eines Fahrzeugantriebstrangs stetig relevanter. Die wahrgenommene Geräuschqualität des Motoraggregates nimmt hierbei eine Schlüsselrolle ein. Aufgrund der Ausprägung einzelner Störgeräusche wird jene Geräuschqualität negativ beeinflusst. Diese als unangenehm empfundenen Geräuschkomponenten gilt es im Rahmen der Fahrzeugentwicklung weiter zu reduzieren, wobei die Identifikation und Bewertung störender Geräuschanteile am Motorgesamtgeräusch Voraussetzungen für eine effektive Akustikoptimierung sind. Vor allem das impulshafte Tickergeräusch wird bei Otto-DI-Motoren als besonders lästig eingestuft, weswegen dieser Beitrag darauf abzielt, die tickernden Geräuschanteile aus dem Gesamtgeräusch zu analysieren und zu bewerten. Hierzu wurde eine empirische Formel entwickelt, welche die tickernden Geräuschanteile in ihrer Intensität in Grenzen einstufen kann. Diese ist rein empfindungsbasiert und besteht aus der Impulshaftigkeit, der Lautheit sowie der Schärfe des Motorgesamtgeräusches. Wie auch bei anderen psychoakustischen Bewertungsskalen wurde die Benotung von 1 (sehr tickernd) bis 10 (nicht tickernd) vorgenommen. Anhand von Hörversuchen mithilfe einer Expertenjury konnte die Tickergeräuschbewertungsformel anschließend verifiziert werden. Hiernach kann präzise ausgesagt werden, in welchen Motorkennfeldbereichen das Tickergeräusch die Angenehmheit des Motorgesamtgeräusches untergräbt. KW - Messtechnik KW - Geräuschentwicklung KW - Psychoakustik KW - Schallentstehung Y1 - 2021 SN - 978-3-948749-02-6 U6 - https://doi.org/10.25673/36611 SP - 65 EP - 86 PB - Otto-von-Guericke-Universität CY - Magdeburg ER - TY - CHAP A1 - Brückl, Oliver A1 - Wildfeuer, M. A1 - Schächinger, J. T1 - Systemdienstleistungen durch Biogasanlagen T2 - Biogas in der Landwirtschaft - Stand und Perspektiven: 7. FNR/KTBL-Onlinetagung 29.-30.09.2021, Darmstadt KW - Biogasanlage Y1 - 2021 SN - 978-3-945088-83-8 SP - 92 EP - 101 CY - Darmstadt ER - TY - CHAP A1 - Jupke, Michael A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael ED - Pinker, Jiří T1 - Bidirectional DC-DC Converter with Digital Droop Parameterization T2 - 26th 2021 International Conference on Applied Electronics (AE): 7-8 Sept. 2021 Pilsen, Czech Republic N2 - The key for decentralized battery systems is a robust and communication-less control strategy for autonomous power sharing of parallel-connected DC-DC converters. Battery systems improve the reliability and quality of power supply in renewable energy systems and enable power supply for off-grid, mobile applications, including islanded grids, home storage, and electric vehicles. In many cases, components with different electrical properties require different voltage levels. An adaptation is consequently essential and is normally implemented in DC grids for the batteries via bidirectional DC-DC converters. The power flow in both directions can thus be ensured. To achieve a power distribution in parallel connected DC-DC converters, a droop control in the form of a virtual internal resistor can be used. This paper presents a novel approach of a DC-DC converter with a digitally parameterizable droop resistor, whose voltage regulation is based on an analog operational amplifier circuit to ensure low delays and robustness. The droop resistor is adjusted with a microcontroller, which offers the possibility to apply a higher-level control for load sharing via an interface. Mathematical correlations are used to clearly define the parameters of the control. Furthermore, the circuit was completely simulated and tested in the hardware setup. The shown results verify the functionality and indicate only minor deviations. Therefore, this circuit is important for future use in distributed battery systems. KW - battery storage plants KW - DC-DC power convertors KW - power convertors KW - distributed power generation KW - microcontrollers KW - voltage regulators KW - voltage control KW - power generation control KW - power grids Y1 - 2021 SN - 978-80-261-0972-3 U6 - https://doi.org/10.23919/AE51540.2021.9542920 SP - 1 EP - 6 PB - Institute of Electrical and Electronics Engineers ER - TY - CHAP A1 - Reindl, Andrea A1 - Singer, Thomas A1 - Meier, Hans A1 - Niemetz, Michael A1 - Park, Sangyoung T1 - Framework to Test DC-DC Converters Developed for a Decentralized Battery Management System T2 - 2021 International Conference on Applied Electronics (AE): 7-8 Sept. 2021, Pilsen, Czech Republic N2 - DC- DC converters control the power flow and thus the power distribution between the components on different voltage levels. They are essential for (dis)charging batteries and influence the safety and stability of the entire battery management system (BMS). Therefore, testing the functionality and the reliability of DC-DC converters is crucial. This is especially true for decentralized battery management systems (DBMS), where multiple nodes communicate to collectively control the system. The used DC-DC converters are modified to parameterize them during operation via microcontroller interfaces. Integrating the communication into the control loop requires an analysis of the control behavior due to additional delays. Therefore, this paper proposes a framework to test DC-DC converters considering the control and communication perspectives. The response time, the control accuracy and stability of these DC-DC converters, e.g., under continuous and abrupt load changes, are measured in automated tests. The dedicated software framework simulates the DBMS and stimulates the hardware components (e.g. electronic loads, data acquisition) via respective interfaces (CAN, RS232). This allows the test of various DC-DC converters with flexibly adaptable load and power generation profiles. An initial application validates the test framework by verifying the aforementioned aspects and thus the applicability of a DC-DC converter within the DBMS. KW - Batteries KW - Battery management system KW - Battery management systems KW - Control systems KW - DC-DC converter KW - DC-DC power converters KW - decentralized control KW - hardware in the loop testing KW - object oriented programming KW - Power system stability KW - Python KW - Stability analysis KW - system testing KW - Time measurement Y1 - 2021 U6 - https://doi.org/10.23919/AE51540.2021.9542882 SP - 1 EP - 6 PB - IEEE ER - TY - CHAP A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael A1 - Park, Sangyoung T1 - Decentralized Battery Management System with Customized Hardware Components T2 - IEEE 19th Student Conference on Research and Development (SCOReD), Sustainable Engineering and Technology towards Industry Revolution: 23-25 Nov. 2021, Kota Kinabalu, Malaysia N2 - With an increasing number of sold electric vehicles (EVs), a large number of used batteries will be at disposal. How to deal with these resources is one of the major challenges in reducing the environmental impact of batteries throughout their entire life cycle. Heterogeneous cell parameters due to the different usage histories are a challenge for second-life use. The effort and cost of remanufacturing required to test and assemble a new battery pack is a further concern. Systems that combine battery packs/modules without full reassembly offer advantages such as cost and reusability. A decentralized battery management system (DBMS) provides a suitable architecture for such systems involving different types of batteries. In this paper, an architecture for a decentralized, battery state-dependent control is shown. The proposed DBMS supports various types of batteries, is scalable and flexibly adaptable for a wide range of applications. Despite the significant advantages, there are increased requirements to meet for the hardware implementation and the applied control strategies. Therefore, the necessary hardware components and their requirements are described and the hardware implementations are provided. KW - battery fitness KW - Battery management system KW - Battery management systems KW - bidirectional power flow KW - Computer architecture KW - Costs KW - DC-DC power converters KW - decentralized control KW - Electric vehicles KW - Hardware KW - load sharing KW - Microprocessors KW - Renewable energy sources KW - second life battery Y1 - 2021 U6 - https://doi.org/10.1109/SCOReD53546.2021.9652737 SP - 350 EP - 355 PB - IEEE ER - TY - CHAP A1 - Schubert, Martin J. W. A1 - Lee, Wai-Kong A1 - Ooi, Boon Yaik T1 - Quantization and Sampling Effects in Fast Digitally Controlled Switch-Mode DC/DC Buck Converters T2 - 2021 IEEE Industrial Electronics and Applications Conference (IEACon): 22.11.2021 - 23.11.2021, Penang, Malaysia N2 - Software-defined control of DC/DC switch mode power converters features unequaled flexibility compared to analog control. For fast switching converters as recently used for low power applications, digital control may cause steady-state oscillations known as limit cycles. This effect based on a quantized duty cycle is compared to other aberrations such as output ripple voltage, which is inherent to any pulse-width modulator. A distinction is made between DC and AC errors. The latter are divided into synchronous and asynchronous output voltage disturbances. Synchronous AC errors are composed of the switching frequency and its harmonics. KW - aberrations due to digitization KW - digital pulse-width modulation (DPWM) KW - low power DC/DC buck conversion KW - output voltage sampling Y1 - 2021 SN - 978-1-7281-9253-6 U6 - https://doi.org/10.1109/IEACon51066.2021.9654272 SP - 56 EP - 61 PB - IEEE ER - TY - CHAP A1 - Croce, Valeria A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav ED - Bien, Jan T1 - Planning post earthquake surveys: assessments and reconstruction of small historical centres T2 - 1st IABSE Online Symposium 2020, Synergy of culture and civil engineering - history and challenges: Wrocław, Poland, 7-9 October 2020, Proceedings N2 - The contribution presents a methodological procedure for the management and planning of interventions after earthquake events in small historic centres. Reference is made to the case study of Castelluccio di Norcia, a village in the Apennine Mountains affected by the seismic sequence that hit Central Italy in 2016. The earthquake risk of the area and the damaging events of 2016 are critically reviewed. The implementation of cognitive analysis and the application of advanced survey techniques involving the use of nmanned Aerial Vehicles (UAVs) for the purposes of emergency management and monitoring of damaged areas are analysed. The outcomes, combined with the direct involvement of the local population, represent a complete and integrated approach allowing the definition of a) possible intervention strategies, b) related decision criteria and c) practical recommendations for the reconstruction and regeneration of Castelluccio, and, in general, of small historic centres damaged by catastrophic events. Y1 - 2021 UR - http://toc.proceedings.com/57946webtoc.pdf SN - 978-1-7138-2387-2 SP - 332 EP - 339 PB - Curran Associates Inc CY - Red Hook, NY ER - TY - CHAP A1 - Hänninen, Risto A1 - Niemetz, Michael A1 - Schoepe, Wilfried T1 - Transition to turbulence in oscillatory superflows T2 - ETC 2013 - 14th European Turbulence Conference 2020: 2 September 2013 - 4 September 2013, Lyon, France N2 - The flow of superfluid helium-4 at very low temperatures around an oscillating microsphere has been studied in detail. At small oscillation amplitudes the drag force is linear in velocity amplitude. Above a critical velocity amplitude vc a transition from potential flow to turbulent flow is signaled by a large and nonlinear drag force that scales as (v2 - v2 c ), where vc is found to be independent of temperature (below 1 K) and of driving force. Interestingly, the critical velocity is found to scale as vc ~ √κω, where κ = h/m ≈ 10−7 m2/s (h is Planck's constant and m is the mass of a helium-4 atom) is the circulation quantum of the superfluid vortices and ω/2π is the oscillation frequency ranging from about 120 Hz to 700 Hz. We also observe slightly above vc that the flow pattern is unstable and switches intermittently between potential flow and turbulence. From time series recorded at constant drive and temperature we have investigated the statistical properties of this switching phenomenon. In this talk the universal law vc ~ √κω will be discussed in detail. It can be derived theoretically in various ways: firstly, from a qualitative but very general argument based on the "superfluid Reynolds number" Rs = vl/κ where v is the flow velocity and l is a characteristic length scale, secondly, and in more detail, from Kopnin's equation of the time dependence of the vortex line density, and, finally, we have obtained this law rigorously by dynamical scaling of the equations of motion of vortex dynamics. Y1 - 2020 UR - http://etc14.ens-lyon.fr/openconf/modules/request.php?module=oc_proceedings&action=view.php&a=Accept&id=17 ER - TY - CHAP A1 - Rieger, Anna A1 - Mühlbauer, Christian A1 - Rabl, Hans-Peter A1 - Weber, Rainer T1 - Dissonanz als Bewertungskriterium multi-tonalen Schalls T2 - Fortschritte der Akustik - DAGA 2020: 46. Deutsche Jahrestagung für Akustik Y1 - 2020 UR - https://www.dega-akustik.de/publikationen/online-proceedings/ SP - 788 EP - 791 PB - Deutsche Gesellschaft für Akustik e.V. ER - TY - CHAP A1 - Mühlbauer, Christian A1 - Rabl, Hans-Peter A1 - Rottengruber, Herrmann ED - Siebenpfeiffer, Wolfgang T1 - Development of a Methodology for Acoustic Analysis and Optimization of Mechatronic Fuel Injection Systems T2 - Automotive Acoustics Conference 2019: Proceedings, 5. Internationale ATZ-Fachtagung Fahrzeugakustik N2 - To identify the sound quality of fuel injection systems as a frontloading measure, a system test bench has been developed that simulates the structure and airborne noise emission. The setup of the system test bench includes an assembly of the acoustical relevant engine parts and an encapsulated drive for the high-pressure pump. A specific control unit enables a high variability for the operation strategy of the injection system. The focus of this study is on the development of a methodology to analyze and optimize the sound quality of gasoline direct injectors in critical operation points by suitable active means. For this, the injection parameters in engine idle have been identified and subsequently transferred to the system test bench. Additionally, the injection parameters have been optimized acoustically and the impacts on the key functions regarding injection rating and shot-to-shot scattering of the injected fuel mass are discussed. Y1 - 2020 SN - 978-3-658-27668-3 U6 - https://doi.org/10.1007/978-3-658-27669-0_15 SP - 211 EP - 225 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Reindl, Andrea A1 - Meier, Hans A1 - Niemetz, Michael ED - Brinkmann, André ED - Karl, Wolfgang ED - Lankes, Stefan ED - Tomforde, Sven ED - Pionteck, Thilo ED - Trinitis, Carsten T1 - Scalable, Decentralized Battery Management System Based on Self-organizing Nodes T2 - Architecture of computing systems - ARCS 2020: 33rd international conference, Aachen, Germany, May 25-28, 2020, proceedings N2 - Due to the transition to renewable energy sources and the increasing share of electric vehicles and smart grids, batteries are gaining in importance. Battery management systems (BMSs) are required for optimal, reliable operation. In this paper, existing BMS topologies are presented and evaluated in terms of reliability, scalability and flexibility. The decentralisation of BMSs and associated advantages are shown. A scalable, reconfigurable BMS based on a distributed architecture of self-organized, locally controlled nodes is proposed. For distributed system control, producers, batteries and consumers each are equipped with a local microcontroller based control unit, which monitors and controls the local parameters with its own computing and communication resources. Features, advantages and challenges to overcome of the proposed approach are described. KW - Availability Decentralized control KW - Battery management systems KW - Controller Area Network KW - distributed management KW - fault tolerant control KW - Multi-microcomputer system KW - Reconfigurable architectures KW - Renewable energy sources KW - Scalability KW - Topology Y1 - 2020 SN - 978-3-030-52793-8 U6 - https://doi.org/10.1007/978-3-030-52794-5_13 VL - 12155 SP - 171 EP - 184 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Anders, M. A1 - Briem, Ulrich A1 - Novak, G. A1 - Steinbach, G. ED - Katterfeld, André ED - Krause, Friedrich ED - Pfeiffer, Dagmar ED - Richter, Klaus T1 - Neue VDI-Richtlinie für die Seiltriebauslegung T2 - 28. Internationale Kranfachtagung 2020 "Kran 4.0: Potenziale der Digitalisierung", 4. und 5. März 2020, Magdeburg Y1 - 2020 SN - 978-3-947068-08-1 SP - 59 EP - 72 PB - LOGiSCH GmbH CY - Magdeburg ER - TY - CHAP A1 - Diamantidis, Dimitris A1 - Sýkora, Miroslav T1 - Reliability Differentiation and Uniform Risk in Standards BT - a Critical Review and a Practical Appraisal: kriticki pregled i prakticna ocjena T2 - Scientific Symposium Future Trends in Civil Engineering, Zagreb,Croatia, 17 October 2029 N2 - Reliability of structures and infrastructures is a major issue in structural engineering. Structural standards have traditionally been mainly concerned with public safety preventing loss of life or injury; this view has been shifting in recent years towards minimisation of economic loss. This contribution discusses the reliability differentiation principle in modern standards. Its aim is to achieve uniform risk levels for the various classes of structures. Codified criteria for reliability differentiation and risk informed decisions inherent in standards and especially in the Eurocodes are critically reviewed. It is shown that the classification of structures based on consequences of failure is an approach that has not been widely implemented in everyday design. Practical rules for the classification and implementation in design are needed and related proposals are presented. T2 - Razlikovanje pouzdanosti i ujednacenost rizika u propisima Y1 - 2020 U6 - https://doi.org/10.5592/CO/FTCE.2019.11 SP - 241 EP - 260 ER - TY - CHAP A1 - Wagner, Marcus A1 - Al-Abadi, Ali A1 - Buchner, Stefan ED - López-Fernández, Xose M., T1 - A Numerical-Based Model to Determine the Resonance of the Steel Cores of Transformers T2 - ARWtr 2022 proceedings : 2022 7th Advanced Research Workshop on Transformers (ARWtr), October (23)24-26, 2022, Baiona, Spain N2 - The laminated steel core of transformers is one of the main sources of the generated sound, as it is excited by different electromagnetic effects during its normal operation. If the core is excited in its eigenfrequencies, the sound generated by a transformer will increase significantly. Therefore, knowledge of the core’s eigenmodes and -frequencies in an early design stage can decrease expenses by avoiding costly modifications that might be required to avoid the sound levels exceeding the specified values after the final factory acceptance test. The current study focuses on developing a core resonance model to determine the eigenmodes and -frequencies of a transformer core. The core’s geometry was simplified to a connected-beam structure and a numerical-based approach was applied. The accuracy of the developed model was validated against finite element method (FEM), using ANSYS on a reference core model. Y1 - 2022 SN - 978-84-09-45157-9 U6 - https://doi.org/https://doi.org/10.23919/ARWtr54586.2022.9959938 SP - 36 EP - 41 PB - IEEE ER - TY - CHAP A1 - Grab, Robin A1 - Rauch, Johannes A1 - Götz, Rebekka A1 - Brückl, Oliver A1 - Eichner, Stefan A1 - Engel, Bernd T1 - Q-Dynamik: Blindleistungsstellgeschwindigkeiten im Verteilnetz T2 - Zukünftige Stromnetze: 27.-28. Januar 2021, 03.-04. Februar 2021, Tagungsunterlagen N2 - Mit der Energiewende geht eine starke Dezentralisierung der Energieeinspeisung einher. So sind im Deutschland des Jahres 2020 rund 31.000 Windenergieanlagen (WEA) in Betrieb, während bei der Solarenergie vor kurzem die zweimillionste Photovoltaik-Anlage (PVA) installiert wurde. Fast alle diese dezentralen Energieressourcen (DER) sind nach den Einspeiserichtlinien der Vergangenheit und der Gegenwart in der Lage, Blindleistung bereitzustellen, um die Spannung im Netz zu regeln und zum Blindleistungsausgleich beizutragen. Weitere potentielle dezentrale Blindleistungsquellen wie Blockheizkraftwerke, Kompensationsanlagen und perspektivisch sogar Verbraucher und Speicher sind im Verteilnetz zu finden. Durch den stetigen Rückbau konventioneller Großkraftwerke, welche dem Übertragungsnetz bisher als Blindleistungsquellen zur Verfügung standen, bedarf es einer Untersuchung mit der Fragestellung, in welchem Maß die neue Erzeugungslandschaft auch in diesem Feld als Ersatz dienen kann. Ein mögliches Hindernis für einen breitangelegten Einsatz von DER zu Zwecken des spannungsebenenübergreifenden Blindleistungsmanagements ist mangelndes Wissen über die Regeldynamik dieser verteilten Blindleistungsquellen. Übertragungs- und Verteilnetzbetreiber, die DER aktiv für Blindleistungsausgleich oder statische Spannungsregelung einsetzen, geben in der Regel ihre Blindleistungsanforderungen in kleineren Stufen mit erheblichen Latenzzeiten zwischen zwei Schritten weiter. Befürchtet wird, dass schnellere Sprünge in der Blindleistungsvorgabe zu instabilen Betriebszuständen oder anderweitigen Fehlfunktionen im Netz führen können. Eine genauere Kenntnis der dynamischen Fähigkeiten vorhandener Blindleistungsquellen sowie der Auswirkungen auf die Netzstabilität und den Netzschutz könnte dazu beitragen, die Geschwindigkeit der Blindleistungsbereitstellung zu optimieren und somit temporäre Spannungsschwankungen und -verluste zu minimieren und die Spannungsstabilität insgesamt zu verbessern. Durch eine entsprechende Regelungs- und Einsatzstrategie kann ein optimales Zusammenspiel der verschiedenen Technologien zur Deckung der Blindleistungsbedarfe für unterschiedliche Zeitbereiche erzielt werden. Hierfür ist eine genaue Kenntnis der Blindleistungsstellgeschwindigkeiten und des dynamischen Regelverhaltens erforderlich. Dieser Beitrag stellt dazu Ergebnisse aus dem Forschungsprojekt „Q-Integral“ vor. Um die relevanten Zeitkonstanten der Blindleistungsbereitstellung vollständig aufzuführen, werden zunächst typische Kommunikationszeiten für die Übermittlung von Sollwerten diskutiert. Anschließend werden Untersuchungen zu theoretischen und praktischen Reaktionszeiten verschiedener Blindleistungsquellen vorgestellt. Dafür werden verschiedene Technologien wie Umrichter für PVA, Batteriespeicher und WEA sowie Synchrongeneratoren, die bei thermischen Kraftwerken die dominierende Technologie sind, betrachtet. Abschließend werden diese Werte mit realen Blindleistungsstellgeschwindigkeiten von ausgedehnten Wind- und Solarkraftwerken verglichen. KW - Blindleistung KW - Blindleistungsmanagement KW - Q-Dynamik KW - Blindleistungsquellen KW - Verteilungsnetz Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58762 SN - 978-3-948176-12-9 SP - 46 EP - 55 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - JOUR A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Achieving Optimal Reactive Power Compensation in Distribution Grids by Using Industrial Compensation Systems JF - Electricity N2 - 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. KW - Blindleistung KW - Blindleistungsmanagement KW - Industriebetriebe KW - Optimal Power Flow KW - Reactive Power Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-59139 N1 - Corresponding author: Johannes Rauch VL - 4 IS - 1 SP - 78 EP - 95 PB - MDPI CY - Basel ER - TY - JOUR A1 - Kahl, Matthias A1 - Krause, Veronika A1 - Hackenberg, Rudolf A1 - Ul Haq, Anwar A1 - Horn, Anton A1 - Jacobsen, Hans-Arno A1 - Kriechbaumer, Thomas A1 - Petzenhauser, Michael A1 - Shamonin (Chamonine), Mikhail A1 - Udalzow, Anton T1 - Measurement system and dataset for in-depth analysis of appliance energy consumption in industrial environment JF - tm - Technisches Messen N2 - 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. KW - appliance monitoring KW - DAQ KW - NILM Y1 - 2019 U6 - https://doi.org/10.1515/teme-2018-0038 VL - 86 IS - 1 SP - 1 EP - 13 PB - De Gruyter ER - TY - CHAP A1 - Wagner, Marcus A1 - Lehrer, Tobias A1 - Franke, Markus A1 - Al-Abadi, Ali A1 - Gamil, Ahmed T1 - A Tank Resonance Model for Power Transformers T2 - ARWtr 2022 proceedings, 2022 7th Advanced Research Workshop on Transformers (ARWtr): October (23)24-26, 2022, Baiona, Spain N2 - 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. Y1 - 2022 U6 - https://doi.org/10.23919/ARWtr54586.2022.9959917 SP - 7 EP - 12 PB - IEEE ER - TY - JOUR A1 - Weber, Karsten A1 - Haug, Sonja T1 - Ist automatisiertes Fahren nachhaltig? BT - Entwicklungstendenzen und Forschungsüberlegungen angesichts geringer Akzeptanz JF - TATuP - Zeitschrift für Technikfolgenabschätzung in Theorie und Praxis N2 - Automatisiertes Fahren stößt derzeit noch auf große Skepsis. Eine disruptive Strategie bei der Einführung (voll-)automatisierten Fahrens könnte daher auf fehlende Akzeptanz treffen. Um dem zu entgehen, laufen evolutionäre 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. KW - driver assistance systems KW - automated driving KW - acceptance KW - sustainability Y1 - 2018 U6 - https://doi.org/10.14512/tatup.27.2.16 VL - 27 IS - 2 SP - 16 EP - 22 PB - Karlsruhe Institute of Technology (KIT) ER - TY - THES A1 - Hartweg, Johanna T1 - Analyse des Einflusses verschiedener Arbeitspunkte auf die wirkleistungsabhängige Spannungssensitivität an einem Mittelspannungsnetzknoten N2 - Im Rahmen dieser Arbeit erfolgt die Untersuchung der wirkleistungsabhängigen Spannungssensitivität an den Knoten eines Mittelspannungsnetzstranges. Hierfür 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 Abhängigkeit von der Spannung des untersuchten Netzknotens. Hierbei steigt die Sensitivität bei fallenden Spannungswerten. Diese können sowohl durch Wirk- und Blindleistungsbelastungen als auch durch eine veränderte Referenzspannung am Umspannwerk bedingt werden. Darüber hinaus liegt eine Beeinflussung durch die Wirkleistungsbelastung und deren Verteilung über den Netzstrang hinweg vor. Je höher die Belastung der Leitung bis zum Knoten der Flexibilität ausfällt sowie je stärker sich die Last hin zu diesem Punkt verlagert, desto höher ist die Sensitivität. Dies gilt ebenfalls für Arbeitspunkte mit gleichbleibender Spannung in den betrachteten Knoten. Des Weiteren wird die Anpassung eines multiplen linearen Regressionsmodells vorgenommen. Dieses ermöglicht eine Abschätzung der Sensitivitätswerte durch die Kenntnis einiger, die Belastungssituation des Netzes bestimmender Parameter. KW - Netzmodell KW - Sensitivitätsanalyse KW - Arbeitspunktabhängigkeit Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-55648 CY - Regensburg ER - TY - RPRT A1 - Gerhards, Christoph A1 - Weber, Urban A1 - Klafka, Peter A1 - Golla, Stefan A1 - Hagedorn, Gregor A1 - Baumann, Franz A1 - Brendel, Heiko A1 - Breyer, Christian A1 - Clausen, Jens A1 - Creutzig, Felix A1 - Daub, Claus-Heinrich A1 - Helgenberger, Sebastian A1 - Hentschel, Karl-Martin A1 - von Hirschhausen, Christian A1 - Jordan, Ulrike A1 - Kemfert, Claudia A1 - Krause, Harald A1 - Linow, Sven A1 - Oei, Pao-Yu A1 - Pehnt, Martin A1 - Pfennig, Andreas A1 - Präger, Fabian A1 - Quaschning, Volker A1 - Schneider, Jens A1 - Spindler, Uli A1 - Stelzer, Volker A1 - Sterner, Michael A1 - Wagener-Lohse, Georg A1 - Weinsziehr, Theresa T1 - Klimaverträgliche Energieversorgung für Deutschland – 16 Orientierungspunkte T2 - Diskussionsbeiträge der Scinetists for Future ; 7 N2 - Als fairer Beitrag Deutschlands zur Einhaltung der globalen 1,5-Grad-Grenze werden 16 Orientierungspunkte für eine klimaverträgliche Energieversorgung vorgestellt. Es wird davon ausgegangen, dass hierfür die deutschen energiebedingten CO2-Emissio­nen in etwa 15 Jahren weitgehend auf Null sinken müssen. Energieeinsparung hilft, den notwendigen Ausbau von regenerativen Erzeugungskapazitäten zu verringern. Der Verkehrssektor kann ebenso wie die Bereiche Prozess- und Gebäudewärme 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 Energieträger 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. Schätzungsweise kann der Elektrizitätsbedarf im Jahr 2030 z.B. durch den Ausbau auf ca. 350 GW PV und ca. 150 GW Windkraft nahe­zu voll­ständig regenerativ gedeckt werden. Damit ließe sich eine zum großen Teil elek­tri­fizierte Mobilität und Wärmeversorgung betreiben und ein Teil des benö­tig­ten "grü­nen" Wasserstoffs in Deutschland bereitstellen. Hierfür ist ein jähr­licher Zu­bau von durchschnittlich ca. 30 GW PV und ca. 9 GW Windkraft nötig. Dies ist ca. sechs- (PV) bzw. dreimal (Wind) so hoch wie bisher vorgesehen und verlangt eine ge­sell­schaft­liche Kraftanstrengung. Ein weiter verzögerter Ausbau müsste mit noch deut­lich größeren gesellschaftlichen Anstrengungen für drastische Energieeinspa­run­gen oder Importe erneuerbarer Energie ausgeglichen werden. Insgesamt könnte dies noch deutlich schwieriger zu realisieren sein, als ein ambitionierter Ausbau. Da der Auf­bau der Kapazitäten mehrere Jahre erfordert, ist es möglich nachzusteuern, z. B. wenn erkennbar wird, dass sich ein ausreichend großer globaler Markt für Importe ent­wi­ckelt. Bis dahin ist es aus Verantwortung gegen­über der Zukunft und im Sinne des Pariser Vertrages empfehlenswert, die hier genannten Ausbauziele zu verfol­gen. Grüner, also aus erneuerbaren Energien hergestellter Wasserstoff und daraus abge­lei­tete Syntheseprodukte sind für die Dekarbonisierung von Industrieprozessen, den Flug- und Schiffsverkehr sowie für die Absicherung der Energieversorgung bei Dun­kel­flauten nötig. Ohne die genannten Ausbauziele für Wind und Solar noch drastisch weiter zu erhöhen, stehen diese Produkte für Straßenverkehr und Wärmeversor­gung jedoch nicht in ausreichenden Mengen zur Verfügung. Techniken zum Aus­gleich zwischen Elektrizitätsangebot und -nachfrage sind verfügbar und sollten recht­zeitig auf- bzw. ausgebaut werden. Hierzu gehören: Stromaustausch mit den Nach­barländern, Flexibilisierung des Verbrauchs und Energiespeicherung. Für deren Inte­gration sowie den Ausbau der Netze sollten zügig verbesserte rechtliche Rah­men­bedingungen geschaffen werden. Die Kosten eines klimaverträglichen Energiesystems sind mittel- bis langfristig nicht hö­her als im derzeitigen System. Gleichzeitig entstehen Arbeitsplätze und Export­chan­cen durch Aufbau, Betrieb und Wartung einer regenerativen Energieversorgung in Deutschland und die energetische Gebäudesanierung. Die politischen Rahmenbe­din­gungen entscheiden, ob eine klimaverträgliche Energieversorgung Deutschlands ge­lingt. T2 - Climate-friendly energy supply for Germany - 16 points of orientation KW - Climate KW - Energy System KW - Renewable Energies Y1 - 2021 U6 - https://doi.org/10.5281/zenodo.4409334 ER - TY - CHAP A1 - Rösel, Birgit T1 - A concept of a mainly digitalized course on control theory including problembased practical units and digital supported exams T2 - HEAd'20: Sixth International Conference on Higher Education Advances, June 2 - June 5 2020, Valencia (Spain) N2 - 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. Y1 - 2020 U6 - https://doi.org/10.4995/HEAd20.2020.11112 ER - TY - CHAP A1 - Goetz, Rebecca A1 - Rauch, Johannes A1 - Brückl, Oliver ED - Schulz, Detlef T1 - Techno-economic analysis of reactive power sources T2 - NEIS 2021, Conference on Sustainable Energy Supply and Energy Storage Systems: Hamburg, 13.-14. September 2021 N2 - 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. Y1 - 2021 UR - https://ieeexplore.ieee.org/document/9698281/ SN - 978-3-8007-5651-3 SP - 286 EP - 291 PB - VDE-Verlag ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Konzeptionierung netzplanerischer Prozessansätze zur Ermittlung von Blindleistungskapazitäten zum Ausgleich des Blindleistungsbedarfs in einer Netzregion T2 - Tagungsband Tagung Zukünftige Stromnetze 26./27. Januar 2022 (online) N2 - Um einen sicheren und zuverlässigen Stromnetzbetrieb zu gewährleisten, muss die Spannung im Grundfall als auch bei ungeplanten Ausfällen in definierten Bereichen gehalten werden. Im Übertragungsnetz wird hierfür bisher Blindleistung hauptsächlich aus Blindleistungskompensationsanlagen und konventionellen Großkraftwerken eingesetzt. Zukünftig wird nach §12h EnWG eine marktgestützte Beschaffung dieser Dienstleistung zur Spannungsregelung vorgeschrieben. Zugleich verändert sich der Blindleistungsbedarf der Netzbetriebsmittel durch die Integration erneuerbarer Energieanlagen und der Elektromobilität sowie durch den Netzausbau bei Übertragungs- und Verteilungsnetzbetreibern. Es bedarf somit angepasster Netzbetriebs- und Netzplanungskonzepte für ein technisch effizientes und wirtschaftlich günstiges Blindleistungsmanagement. Dieser Beitrag beschäftigt sich damit, Prozessansätze und Methodiken für ebendieses in der Netzplanung aufzuzeigen, um erforderliche Blindleistungskapazitäten unter minimalen Gesamtkostenaufwand und unter Berücksichtigung einer effizienten Blindleistungsbedarfsdeckung zu bestimmen. Dabei liegt der Fokus verstärkt in der Bedarfsanalyse. KW - Blindleistung KW - Blindleistungsmanagement KW - Netzplanungsprozesse KW - Spannungshaltung KW - Optimierungsverfahren Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58665 SN - 978-3-948176-16-7 SP - 117 EP - 126 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - CHAP A1 - Schweiberer, Philipp A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Entwicklung eines Regelkonzeptes für einen optimierten Blindleistungsabruf auf Basis von Blindleistungspotentialanalysen bei Industriebetrieben im Mittelspannungsnetz T2 - Tagungsband Tagung Zukünftige Stromnetze 26./27. Januar 2022 (online) N2 - Im Zuge der Energiewende ergibt sich ein Wandel in der Struktur des Elektrizitätsversorgungsnetzes. Die Verschiebung der Erzeugungsleistung von konventionellen Großkraftwerken in höheren Netzebenen hin zu dezentralen erneuerbaren Energieanlagen in niedrigeren Netzebenen resultiert sowohl in bidirektionalen Lastflüssen als auch in schwankenden Einspeisecharakteristiken. Des Weiteren folgen durch den Wegfall von Großkraftwerken als Blindleistungsquellen Leistungsdefizite in der Übertragungsnetzebene, die kompensiert werden müssen. Daraus resultieren Herausforderungen an einen sicheren und zuverlässigen Betrieb der Verteil- und Übertragungsnetze. Neue Konzepte müssen für die Erbringung von Blindleistung entwickelt werden, es soll mehr Blindleistung aus dem Verteilungsnetz zur Verfügung gestellt werden, um die Systemstabilität zu wahren. Im Rahmen des Projektes Q-Integral wird das Thema „Blindleistung“ (Q) ganzheitlich untersucht. Es werden dazu verschiedene Erbringungsoptionen für Blindleistung hinsichtlich technischer und wirtschaftlicher Potentiale untersucht, die in ein funktionales und effizientes Blindleistungsmanagement eingebracht werden. Die Untersuchungsansätze dafür sind sowohl spannungsebenen-übergreifend als auch netzbetreiber-übergreifend. 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 können, untersucht. Ziel ist es, das gesicherte und maximale induktive sowie kapazitive Potential zu bestimmen. Das gesicherte kapazitive Potential kann genutzt werden, um Aussagen darüber zu treffen, wie stark dem Spannungsfall im vorgelagerten Netz zu Starklastzeiten entgegengewirkt werden kann. Anhand des gesicherten induktiven Potentials kann ein Spannungsanstieg während 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 Lastgänge als auch das Schaltverhalten der einzelnen Kompensationsanlagen liegen den Berechnungen zugrunde. Um den Austausch der Blindleistung an der Übergabestelle des Betriebs zum Mittelspannungsnetz netzdienlich einzustellen, bedarf es eines geeigneten Regelkonzepts, das neben den BKAs auch weitere Q-Quellen berücksichtigt. Deshalb wird abschließend ein Regelkonzept vorgestellt, das den technisch-optimierten Blindleistungsabruf unter Berücksichtigung mehrerer Blindleistungsquellen behandelt. KW - Blindleistung KW - Blindleistungsmanagement KW - Blindleistungsquellen KW - Blindleistungspotentiale KW - Industriebetriebe Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58704 SN - 978-3-948176-16-7 SP - 224 EP - 233 PB - Conexio-PSE GmbH CY - Pforzheim ER - TY - CHAP A1 - Rauch, Johannes A1 - Brückl, Oliver T1 - Analysis of the correlation behavior between local available information to the overall reactive power of a medium-voltage grid group T2 - Applied Research Conference - ARC 2017, 7 July 2017 München N2 - 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 für 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. KW - Mittelspannungsnetz KW - Blindleistungsmanagement KW - Blindleistung KW - Integration Erneuerbare Energien KW - Potentialerschließung Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58712 SP - 224 EP - 230 CY - München ER - TY - JOUR A1 - Malz, Sebastian A1 - Krenkel, Walter A1 - Steffens, Oliver T1 - Infrared Reflective Wall Paint in Buildings: Energy Saving Potentials and Thermal Comfort JF - Energy and Buildings N2 - 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. KW - Infrared-reflective KW - Wall paint KW - Coating KW - Existing buildings KW - Radiative asymmetry KW - Energy efficiency Y1 - 2020 U6 - https://doi.org/10.1016/j.enbuild.2020.110212 SN - 0378-7788 VL - 224 IS - October PB - Elsevier ER - TY - RPRT A1 - Sterner, Michael A1 - Schumm, Leon A1 - Rank, Daniel A1 - Hofrichter, Andreas T1 - Intelligente Netzpuffer : Abschlussbericht (24.01.2021) KW - Stromspeicher KW - Batterien KW - Netzpuffer KW - Stromnetz Y1 - 2021 N1 - unveröffentlichter Abschlussbericht ER - TY - JOUR A1 - Schulz, Carsten A1 - Schwarz, Colin T1 - Drivetrain fatigue strength characteristics of model-predictive control for wind turbines JF - Wind Energy N2 - 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. Y1 - 2020 U6 - https://doi.org/10.1002/we.2520 VL - 23 IS - 12 SP - 2137 EP - 2149 PB - Wiley 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 - JOUR A1 - Kral, Christian A1 - Haumer, Anton A1 - Haigis, Matthias A1 - Lang, Hermann A1 - Kapeller, Hansjörg T1 - Comparison of a CFD Analysis and a Thermal Equivalent Circuit Model of a TEFC Induction Machine With Measurements JF - IEEE Transactions on Energy Conversion N2 - 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. KW - asynchronous machines KW - computational fluid dynamics KW - electric sensing devices KW - Fluid flow KW - induction machines KW - numerical analysis KW - simulation KW - temperature Y1 - 2009 U6 - https://doi.org/10.1109/TEC.2009.2025428 SN - 0885-8969 VL - 24 IS - 4 SP - 809 EP - 818 PB - IEEE 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 - Ebner, Arno A1 - Haumer, Anton A1 - Simic, Dragan A1 - Pirker, Franz T1 - Interacting Modelica using a Named Pipe for Hardware-in-the-loop Simulation T2 - Modelica 2006, Conference proceedings / 5th International Modelica Conference : September 4 - 5, 2006, Vienna, Austria N2 - 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. Y1 - 2006 UR - https://modelica.org/events/modelica2006/Proceedings/sessions/Session3b1.pdf SP - 261 EP - 266 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 - 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 - 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 - 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 - 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 - 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 - 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 -