TY - CHAP A1 - Eberhart, Philip A1 - Chung, Tek Shan A1 - Haumer, Anton A1 - Kral, Christian T1 - Open Source Library for the Simulation of Wind Power Plants T2 - Proceedings of the 11th International Modelica Conference, Versailles, France, September 21-23, 2015 N2 - This paper presents the new open source Modelica libraryWindPowerPlants. For the economic assessment of either a wind power plant or an entire wind park, the accurate prediction of the energy output is essential. Such prediction is usually performed by means of calculations based on statistical wind data. The proposed WindPowerPlants library is capable of assessing the energy output both for statistical and real wind data based on time domain simulations. In the presented version of the library wind turbine models are modeled with pitch control. The generator models have variable speed and an optional connector to the mains. The entire library is based on power balance conditions and losses are fully neglected. Yet, the library can be extended towards more detailed models considering different types of losses. The structure and components of the library are presented. Simulations examples are shown and compared with reference data. The applicability of the proposed WindPowerPlants library is demonstrated and possible enhancements are discussed. KW - variable speed KW - pitch control KW - Wind power pants KW - energy KW - statistical wind data KW - power Y1 - 2015 U6 - https://doi.org/10.3384/ecp15118929 SP - 929 EP - 936 CY - Linköping ER - TY - JOUR A1 - Kral, Christian A1 - Haumer, Anton A1 - Lee, Sang Bin T1 - A Practical Thermal Model for the Estimation of Permanent Magnet and Stator Winding Temperatures JF - IEEE Transactions on Power Electronics N2 - A thermal model for the determination of the temperatures of interior permanent magnets and stator windings is presented in this paper. The innovation of the model relies on one temperature sensor being located in the stator core of the machine. Such sensor is simple to implement in many applications such as traction or EV, where reliability is critical. The estimated stator winding and permanent magnet temperatures are determined by a simplified thermal lumped element network model with only two time constants. It is shown that the proposed thermal model is very robust due to the structure of the model and the measured stator core temperature. The distortion of the temperature estimates caused by the cooling circuit is inherently accounted for such that the model can be used for robust online prediction of temperatures. Experimental results based on a forced water-cooled interior permanent magnet synchronous machine setup are presented to validate the effectiveness of the presented model. KW - cooling KW - lumped element thermal equivalent circuit model KW - magnetic cores KW - permanent magnet machines KW - permanent magnet synchronous machine KW - stators KW - synchronous machines KW - temperature estimation KW - variable speed KW - dynamic load Y1 - 2014 U6 - https://doi.org/10.1109/TPEL.2013.2253128 SN - 1941-0107 SN - 0885-8993 VL - 29 IS - 1 SP - 455 EP - 464 PB - IEEE ER - TY - CHAP A1 - Kral, Christian A1 - Haumer, Anton A1 - Wöhrnschimmel, Reinhard T1 - Extension of the FundamentalWave Library towards Multi Phase Electric Machine Models T2 - Proceedings of the 10th International Modelica Conference, March 10-12, 2014, Lund, Sweden N2 - Abstract Electric machine theory and electric machine simulations models are often limited to three phases. Up to the Modelica Standard Libray (MSL) version 3.2 the provided machine models were limited to three phases. Particularly for large industrial drives and for redundancy reasons in electric vehicles and aircrafts multi phase electric machines are demanded. In the MSL 3.2.1 an extension of the existing FundamentalWave library has been performed to cope with phase numbers greater than or equal to three. The developed machine models are fully incorporating the multi phase electric; magnetic; rotational and thermal domain. In this publication the theoretical background of the machines models; Modelica implementation details; the parametrization of the models and simulation examples are presented. KW - electric Machine models KW - induction machine KW - Modelica Standard Library KW - multi phase KW - synchronous machine KW - synchronous reluctance machine Y1 - 2014 SN - 978-91-7519-380-9 U6 - https://doi.org/10.3384/ecp14096135 SN - 1650-3686 SN - 1650-3740 SP - 135 EP - 143 PB - Linköping University Electronic Press 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 - 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 -