@inproceedings{HongHyunKangetal., author = {Hong, Jongman and Hyun, Doosoo and Kang, Tae-june and Lee, Sang Bin and Kral, Christian and Haumer, Anton}, title = {Detection and classification of rotor demagnetization and eccentricity faults for PM synchronous motors}, series = {2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011) : Energy conversion innovation for a clean energy future ; Phoenix, Arizona, USA, 17.-22.09.2011}, booktitle = {2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011) : Energy conversion innovation for a clean energy future ; Phoenix, Arizona, USA, 17.-22.09.2011}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4577-0542-7}, issn = {2329-3721}, doi = {10.1109/ECCE.2011.6064103}, pages = {2512 -- 2519}, abstract = {Condition monitoring of rotor problems such as demagnetization and eccentricity in permanent magnet synchronous motors (PMSM) is essential for guaranteeing high motor performance, efficiency, and reliability. However, there are many limitations to the off-line and on-line methods currently used for PMSM rotor quality assessment. In this paper, an inverter-embedded technique for automated detection and classification of PMSM rotor faults is proposed as an alternative. The main concept is to use the inverter to perform a test whenever the motor is stopped, to detect rotor faults independent of operating conditions or load torque oscillations, which is not possible with motor current signature analysis (MCSA). The d-axis is excited with a dc+ac signal, and the variation in the inductance pattern due to the change in the degree of magnetic saturation caused by demagnetization or eccentricity is observed for fault detection. An experimental study on a 7.5kW PMSM verifies that demagnetization and eccentricity can be detected and classified independent of the load with high sensitivity.}, language = {en} } @inproceedings{HongLeeKraletal., author = {Hong, Jongman and Lee, Sang Bin and Kral, Christian and Haumer, Anton}, title = {Detection of airgap eccentricity for permanent magnet synchronous motors based on the d-axis inductance}, series = {8th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics \& Drives (SDEMPED), 2011 // 05. - 08.09.2011, Bologna, Italy}, booktitle = {8th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics \& Drives (SDEMPED), 2011 // 05. - 08.09.2011, Bologna, Italy}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4244-9301-2}, doi = {10.1109/DEMPED.2011.6063651}, pages = {378 -- 384}, abstract = {The majority of the work performed for detecting eccentricity faults for permanent magnet synchronous motors (PMSM) focus on motor current signature analysis (MCSA), as it provides continuous on-line monitoring with existing current sensors. However, MCSA cannot be applied under nonstationary conditions and cannot distinguish faults with load torque oscillations, which are limitations for many PMSM drive applications. In this paper, it is shown that the d-axis inductance, L d , decreases with increase in the severity of eccentricity due to the change in the degree of magnetic saturation, and it is proposed as a new fault indicator. The inverter can be used to perform a standstill test automatically whenever the motor is stopped, to measure L d for eccentricity testing independent of load variations or oscillations, which is not possible with MCSA. An FE and experimental study on a 10hp PMSM verifies that eccentricity can be detected independent of the load with high sensitivity and reliability.}, language = {en} } @inproceedings{HaumerKral, author = {Haumer, Anton and Kral, Christian}, title = {Modeling a Mains connected PWM Converter with Voltage-Oriented Control}, series = {Proceedings of the 8th International Modelica Conference, Technical Univeristy, Dresden, Germany, 20.-22.03.2011}, booktitle = {Proceedings of the 8th International Modelica Conference, Technical Univeristy, Dresden, Germany, 20.-22.03.2011}, publisher = {Link{\"o}ping University Electronic Press}, doi = {10.3384/ecp11063388}, pages = {388 -- 397}, abstract = {The majority of industrial controlled induction machine drives are connected to the mains via a diode bridge. However; if reduction of harmonic currents and / or regenerative operation is desired; replacing the diode bridge by an active front-end (AFE) is required. This paper describes two models of an AFE: a power balance model disregarding switching effects; and an ideal switching model of a pulse width modulation (PWM) converter. Both models are controlled utilizing space phasors in a voltage oriented reference frame. Voltage oriented control (VOC) of the mains converter can be compared with field oriented control (FOC) of a machine converter. Design and parametrization of the main parts—synchronization with mains voltage; current controller and DC voltage controller—are described in detail. Additionally; simulation results proving the implementation and demonstrating possible investigations as well as an outlook on further enhancements are presented.}, language = {en} } @inproceedings{JungreuthmayerBaumlWinteretal., author = {Jungreuthmayer, C. and Bauml, T. and Winter, O. and Ganchev, M. and Kapeller, H. and Haumer, Anton and Kral, Christian}, title = {Heat and fluid flow analysis of an internal permanent magnet synchronous machine by means of computational fluid dynamics}, series = {2011 IEEE International Electric Machines \& Drives Conference (IEMDC 2011) ; Niagara Falls, Ontario, Canada, 15 - 18 May 2011}, booktitle = {2011 IEEE International Electric Machines \& Drives Conference (IEMDC 2011) ; Niagara Falls, Ontario, Canada, 15 - 18 May 2011}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4577-0060-6}, doi = {10.1109/IEMDC.2011.5994651}, pages = {515 -- 520}, abstract = {This paper presents a comprehensive computational fluid (CFD) model of a radial flux permanent magnet synchronous machine with interior magnets. In the CFD model the water jacket cooling and a simplified model of the topology of the distributed stator winding are considered. The heat sources of the CFD model are determined from a finite element analysis of the machine. The numerically determined temperature distributions of the machine are compared with measurement results from sensors located both in the stator and rotor. The particular focus of this paper is the analysis of the temperatures and the heat flow in the air gap and from the stator winding head and the rotor to the inner air.}, language = {en} } @inproceedings{HaumerKral, author = {Haumer, Anton and Kral, Christian}, title = {Motor Management of Permanent Magnet Synchronous Machines}, series = {Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany}, booktitle = {Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany}, editor = {Otter, Martin and Zimmer, Dirk}, publisher = {Link{\"o}ping University Electronic Press}, isbn = {978-91-7519-826-2}, issn = {1650-3686}, doi = {10.3384/ecp12076159}, pages = {159 -- 166}, abstract = {Two state-of-the-art machine designs are mainly used in recent electric and hybrid electric vehicles: asynchronous induction machines with squirrel cage which are robust but need a current component to excite the magnetic field; and permanent magnet synchronous machines which rely on somehow more sensible parts but the magnets are able to excite a magnetic field without current. However; if speed gets high enough to reach the field weakening range; for both machine the field oriented control has to prescribe a field current sufficient to reduce the field not to exceed the voltage limits of the stator circuit. Especially for the permanent magnet synchronous machine this paper investigates whether it is possible to determine an optimal field current for every operation point to minimize either total current consumption or losses.}, language = {en} } @incollection{KapellerHaumerKraletal., author = {Kapeller, Hansj{\"o}rg and Haumer, Anton and Kral, Christian and Grabner, Christian}, title = {Different Designs of Large Chipper Drives}, series = {Electronic Engineering and Computing Technology}, booktitle = {Electronic Engineering and Computing Technology}, editor = {Ao, Sio-Iong and Gelman, Len}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-90-481-8775-1}, doi = {10.1007/978-90-481-8776-8_9}, pages = {93 -- 104}, abstract = {This paper presents two simulation models for two variants of a large chipper drive used in a paper mill. If a slip ring induction motor is used, the impact of a rotor circuit rheostat with respect to starting behavior and heavy duty load impulses can be examined. Furthermore a speed controlled squirrel cage induction machine will be investigated. The modeling language for both drives is Modelica. The simulation results for both drives are compared and discussed.}, language = {en} } @inproceedings{KralHaumerBogomolovetal., author = {Kral, Christian and Haumer, Anton and Bogomolov, Maxim and Lomonova, Elena}, title = {Harmonic wave model of a permanent magnet synchronous machine for modeling partial demagnetization under short circuit conditions}, series = {2012 XXth International Conference on Electrical Machines (ICEM 2012) ; Marseille, France, 2 - 5 September 2012}, booktitle = {2012 XXth International Conference on Electrical Machines (ICEM 2012) ; Marseille, France, 2 - 5 September 2012}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-0142-8}, doi = {10.1109/ICElMach.2012.6349880}, pages = {295 -- 301}, abstract = {This paper proposes a multi domain physical model of permanent magnet synchronous machines, considering electrical, magnetic, thermal and mechanical effects. For each component of the model, the main wave as well as lower and higher harmonic wave components of the magnetic flux and the magnetic potential difference may be considered. The permanent magnets are modeled as discrete azimuthal segments in order to consider possible partial demagnetization effects. For each magnet segment a linearized temperature dependent B-H curve is considered. The main advantage of the presented model is that time transient operational behavior of a permanent magnet synchronous machine can be considered under various electrical, magnetic, thermal and mechanical conditions. The electromagnetic condition of surface magnet machine is compared with finite element analysis.}, language = {en} } @inproceedings{KralHaumerLee, author = {Kral, Christian and Haumer, Anton and Lee, Sang Bin}, title = {Robust thermal model for the estimation of rotor cage and stator winding temperatures of induction machines}, series = {2012 XXth International Conference on Electrical Machines ; Marseille, France, 02.- 05.09.2012}, booktitle = {2012 XXth International Conference on Electrical Machines ; Marseille, France, 02.- 05.09.2012}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-0142-8}, doi = {10.1109/ICElMach.2012.6350127}, pages = {1810 -- 1816}, abstract = {In this paper a new model for the estimation of the stator winding and rotor cage temperatures of induction machines is presented. This model can be used in series applications of machines operated under dynamic load conditions where stator and rotor temperature shall be monitored. The proposed model relies on a simplified lumped element thermal equivalent circuit model where the stator core temperature serves as input quantity. The great advantage of this model is that it covers ambient and cooling conditions inherently. This leads to great simplicity and robustness. The parametrization and validation of the model through experimental data is presented. Advantages, drawbacks and possible implementations are discussed.}, language = {en} } @inproceedings{KralHaumerLee, author = {Kral, Christian and Haumer, Anton and Lee, Sang Bin}, title = {Innovative thermal model for the estimation of permanent magnet and stator winding temperatures}, series = {2012 IEEE Energy Conversion Congress and Exposition (ECCE 2012) ; Raleigh, NC, USA 15.09.-20.09.2012}, booktitle = {2012 IEEE Energy Conversion Congress and Exposition (ECCE 2012) ; Raleigh, NC, USA 15.09.-20.09.2012}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-0803-8}, issn = {2329-3721}, doi = {10.1109/ECCE.2012.6342386}, pages = {2704 -- 2711}, abstract = {In this paper an innovative thermal model for the determination of the temperatures of the permanent magnets and stator windings is presented. This model relies on one temperature sensor located in the stator core of the machine. The estimated stator winding and permanent magnet temperatures are determined by a simplified thermal lumped element network model with only two time constants. Due to the structure of the model and the measured stator core temperature the proposed thermal model is very robust. Distortion of the cooling circuit are inherently sensed such that the model can be used for the online prediction of temperatures. Experimental results based on an interior permanent magnet synchronous machine are presented to validate the presented model.}, language = {en} } @inproceedings{KralHaumer, author = {Kral, Christian and Haumer, Anton}, title = {The New FundamentalWave Library for Modeling Rotating Electrical Three Phase Machines}, series = {Proceedings of the 8th International Modelica Conference; March 20th-22nd; Technical Univeristy; Dresden; Germany}, booktitle = {Proceedings of the 8th International Modelica Conference; March 20th-22nd; Technical Univeristy; Dresden; Germany}, publisher = {University Electronic Press}, address = {Link{\"o}ping}, isbn = {978-91-7393-096-3}, issn = {1650-3686}, doi = {10.3384/ecp11063170}, pages = {170 -- 179}, abstract = {This paper introduces the new FundemantalWave library which is included in the Modelica Standard Library 3.2. The presented Modelica package provides models and components of rotating electrical three phase machines. The presented electrical machine models are fully compatible with the original Machines library of the electrical domain but rely on the concept of the magnetic potential and magnetic flux fundamental waves. In this article; the connector concept; the components and electric machine models of the FundemantalWave package will be explained. Additionally; the didactic advantages and the flexibility of the proposed package in with respect to considering more enhanced and sophisticated effects will be discussed.}, language = {en} }