{"title":"Identification of design rules for interior PM motors with different cooling systems","authors":"A. Fatemi, D. Ionel, N. Demerdash","doi":"10.1109/IEMDC.2015.7409218","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409218","url":null,"abstract":"The conventional scaling rules for the optimal design of electric machines are best suited for naturally cooled machines with stator winding current densities less than 4A/mm2. In this paper, through a comprehensive sensitivity analysis, first, it is demonstrated that the correlations between some geometric variables and the performance metrics of interior permanent magnet (IPM) motors vary significantly with respect to the stator winding current density. For this purpose, three current densities are selected so as to approximately account for naturally cooled, fan-cooled and liquid-cooled machines. Subsequently, a parameterized IPM motor is optimized at these current densities through a large-scale design optimization algorithm by evaluating a total of 20,000 design candidates. The 100 best designs from each group are then identified and extracted to investigate the scaling rules for the optimal design of such IPM motors with different cooling systems. The outcomes of the study are in correspondence with the conventional design principles for naturally cooled machines. Nevertheless, it is illustrated that these rules vary for fan-cooled and liquid-cooled machines owing to the increased ampere loading, and also heavy saturation of the magnetic core in such machines. A configuration of a 50 hp, 48-slot, 8-pole IPM motor with a single-layer v-type magnet is used as the benchmark of this study.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"602 1","pages":"1228-1234"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77355893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Z. Xu, A. La Rocca, S. Pickering, C. Eastwick, C. Gerada, S. Bozhko
{"title":"Mechanical and thermal design of an aeroengine starter/generator","authors":"Z. Xu, A. La Rocca, S. Pickering, C. Eastwick, C. Gerada, S. Bozhko","doi":"10.1109/IEMDC.2015.7409278","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409278","url":null,"abstract":"The paper describes the mechanical and thermal design of a high speed, high power density synchronous permanent magnet machine for an aero engine starter generator system with a power rating of 150 kW and maximum speed of 32,000 rpm. The electrical machine is designed to minimise the weight and maximise the efficiency so both mechanical and thermal aspects are considered. The cooling strategy adopts an inner stator sleeve for enhanced cooling of the stationary components whilst minimising the windage loss. Finite Element Analysis (FEA) is used for the static structural analyses of critical components of the machine and the dynamic performance of the rotating shaft. Heat transfer phenomena are also investigated by the means of Computational Fluid Dynamics (CFD) and Lumped Parameter Thermal Network (LPTN) for the optimisation of the proposed cooling arrangement and prediction of the machine temperature distribution.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"41 1","pages":"1607-1613"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76207236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Computationally efficient 3D FEM rotor eddy-current loss calculation for permanent magnet synchronous machines","authors":"M. van der Geest, H. Polinder, J. Ferreira","doi":"10.1109/IEMDC.2015.7409208","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409208","url":null,"abstract":"Rotor eddy-current loss calculation by means of 3D finite element analysis is often necessary during later design stages of a new machine, but can still be very time-consuming. This paper proposes two FEM-based methods that potentially require less time to solve than a transient model of the complete machine geometry and are relatively straightforward to implement. Both methods apply an airgap boundary condition obtained from a limited number of solutions of a full 3D model, to a model containing only the rotor geometry. An important property of both methods is that they can account for shielding effects in the rotor. The performance of the methods in terms of accuracy and speed is demonstrated and guidelines for implementation are presented, showing that the rotor losses can be calculated 2-3 faster without loss of accuracy. Finally, using the methods a number of rotor loss trends are confirmed.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"43 1","pages":"1165-1169"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75731567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Seamless grid interaction for a switched doubly-fed machine propulsion drive","authors":"A. Banerjee, S. Leeb, J. Kirtley","doi":"10.1109/IEMDC.2015.7409191","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409191","url":null,"abstract":"Switched doubly-fed machine (DFM) drives can provide shaft speed control over a wide range without the need for a full power converter. Seamless shaft behavior across the complete speed range is achieved using a thyristor-based transfer switch in the stator of the DFM and appropriate control in the rotor converter. The drive must also operate without glitch with respect to the ac source. The seamless grid interaction is critical in applications such as in ship propulsion, where the drive may consume a major share of the generated power. This paper presents a coordinated control of the rotor converter that can ensure seamless operation for the switched-DFM drive with respect to the ac source. A laboratory setup emulating a ship microgrid is used to demonstrate the drive performance under different loading conditions.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"29 1","pages":"1049-1055"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81997408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Dang, J. Mayor, J. Restrepo, S. A. Semidey, R. Harley, T. Habetler
{"title":"High speed SRM control considering the inductance profile of a flux-bridge rotor","authors":"J. Dang, J. Mayor, J. Restrepo, S. A. Semidey, R. Harley, T. Habetler","doi":"10.1109/IEMDC.2015.7409276","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409276","url":null,"abstract":"The closed-loop speed control for a high speed switched reluctance machine (SRM) is studied in this paper. A speed-and-current dual closed-loop control scheme is selected for speeds as high as 50 krpm. The novelty of the proposed control method is inclusion of the inductance profile selection for a flux-bridge rotor. In this paper, the nonlinear SRM is modeled in a linearized form by small signal equations, and then transfer functions are used to calculate the appropriate controller coefficients. The proposed control scheme is designed and its performance is evaluated using Matlab/Simulink.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"9 1","pages":"1593-1599"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86471366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of saturation on rotational flux distribution in hydro generators","authors":"J. C. Akiror, P. Pillay, A. Merkhouf","doi":"10.1109/IEMDC.2015.7409112","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409112","url":null,"abstract":"Uprating of hydro generators requires studies into the potential areas of failure like hotspots within the machine core. Rotational core losses cause localized heating of the core therefore understanding the distribution and behavior of rotational flux in the machine is key. This paper studies the distribution of rotational flux in a hydro generator as the core material is saturated. The percentage of rotational flux in the stator increases as the material is saturated especially for aspect ratios above 0.6. This can affect the loss distribution in the machine. Moreover experimental core loss data of non-sinusoidal flux densities in various parts of the machine at no load and full load operation are also presented.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"3 1","pages":"550-554"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78469555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantifying eddy current effects on a magnetic thrust bearing used in a high speed electrical machine","authors":"Arunvel Kailasan, Radu Curiae","doi":"10.1109/IEMDC.2015.7409229","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409229","url":null,"abstract":"Magnetic bearings are now consistently used in high speed motors owing to their many advantages over traditional bearings. However, the bandwidth of magnetic bearings may be severely limited due to the occurrence of eddy currents which cause power loss and instability in nominal operation. This problem is generally overcome in radial magnetic bearings by laminating the core. This solution is difficult to implement in a thrust magnetic bearing mainly due to high cost associated with complexity of machining and assembly. As a result, the solid thrust stator is fragmented into several pieces, which are mounted onto a common plate. In several applications, it is not possible to add this common plate due to size limitations. To improve the controller response, it is thought that a single slit can be introduced. To quantify this improvement, a Finite element model study was conducted. By extension, the minimum number of slits that need to be introduced to keep eddy currents at a minimum was also studied. This paper studies and compares the eddy current effects in different thrust bearing configurations which include a single slit, double slit, four slit and eight slit thrust magnetic bearing. Finite element analysis techniques are used to model and simulate these different configurations. Based on these results several configurations are being built to validate and test the models.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"7 1","pages":"1299-1304"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87381175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A study on a energy management of EDLC for unbalanced input voltage three level inverter","authors":"Yoshiki Ohno, K. Kondo","doi":"10.1109/IEMDC.2015.7409259","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409259","url":null,"abstract":"There are still several technical problems with batteries for electric vehicles (EVs), such as short life of batteries on board, and less driving distance. An unbalanced input voltage three level inverter have been studied for a traction system for battery and EDLCs (Electric Double Layer Capacitors) hybrid EVs. This system is expected to reduce the loss and mass compared to a system with DC/DC chopper. When applying EDLCs as energy storage device, the energy management is essential through the whole operation of the motor because the energy density of EDLC is not so high and it can be charged only by the regenerative brake. In this paper, a method to manage energy of EDLC is proposed and it is examined by 1kW class experimental system.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"1 1","pages":"1488-1493"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89624839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effects of an electromagnetic shield and armature teeth on the short-circuit performance of a direct drive superconducting generator for 10 MW wind turbines","authors":"Dong Liu, H. Polinder, A. Abrahamsen, J. Ferreira","doi":"10.1109/IEMDC.2015.7409137","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409137","url":null,"abstract":"To reduce the cost of energy of offshore wind energy conversion, large individual wind turbines of 10 MW or higher power levels are drawing more attention and expected to be desirable. Conventional wind generator systems would be rather large and costly if scaled up to 10 MW. Direct drive superconducting generators have been proposed to reduce the generator size, because the electrical machines with superconducting windings are capable of achieving a higher torque density. However, a superconducting machine is likely to produce an excessive torque during a short circuit because of its small reactance. An electromagnetic (EM) shield between the rotor and the stator as well as iron or non-magnetic composite (NMC) armature teeth affects the sub-transient reactance of a superconducting machine so that they play a role in the short-circuit performance of a superconducting wind generator. This paper presents a 10 MW superconducting generator design and studies the effects of material, thickness and position of an EM shield and the effects of NMC and iron armature teeth on the torque and the field current density during a three-phase short circuit at the generator terminal. One result shows that the short circuit torque is not able to be effectively reduced by varying the EM shield and the armature tooth material. The other result shows that the field current density is likely to exceed its critical value during a short circuit although the EM shield material and the armature tooth material take some effect.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"74 1","pages":"709-714"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90593828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A finite control set model predictive direct torque control for the PMSM with MTPA operation and torque ripple minimization","authors":"Qian Liu, K. Hameyer","doi":"10.1109/IEMDC.2015.7409152","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409152","url":null,"abstract":"In this paper, a Lyapunov based finite control set model predictive direct torque control for the permanent magnet synchronous machine (PMSM) is proposed. In the proposed control scheme, the finite control set prediction and the Lyapunov theory are combined to minimize the torque ripple. The 8 voltage vectors of the 2-level converter are utilized as a finite control set for the torque prediction of the PMSM. A cost function considering the torque error, the Maximum Torque per Ampere (MTPA) operation and the current limitation is introduced. Comparing to the conventional finite control set predictive control, the dominant part of the cost function is utilized as a Lyapunov function to estimate the duty cycle of each voltage vector. An optimum voltage can be obtained by the optimum voltage vector from the 8 vectors and their duty cycles. A small sampling frequency and a fixed switching frequency can be realized when compared to the conventional finite set model predictive control. In the end, the simulation and experimental results validate the performance of the proposed control scheme.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"2 1","pages":"804-810"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90642150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}