Comparative Study on Triple 3-Phase PMA-SynRM with Distributed Winding and Concentrated Winding
Wang Bo1, Xu Wenhan1, Zha Chencheng1, Liu Chaohui2, Cheng Ming1, Hua Wei1
1. School of Electrical Engineering Southeast University Nanjing 210096 China; 2. Powertrain Department National New Energy Vehicle Technology Innovation Center (NEVC) Beijing 100176 China
Abstract:PM Assisted Synchronous Reluctance Machine (PMA-SynRM) receives increased interest in industry applications. It reduces the PM usage and offsets the torque reduction by employing reluctance torque, achieving comparable performance with a lower cost. This type of machine features low PM flux linkage, suitable for fault-tolerant applications. The machine drive performance and fault-tolerant ability are closely related to their windings. Therefore, this paper compares two fault-tolerant motor topologies with multiple 3-phase distributed winding and multiple 3-phase concentrated winding. First, the two motors are designed under the same technical specifications and operate at the rated point with 24 N·m torque at 2 000 r/min. For each design sample, simulation calculations are conducted in Flux, and the relevant data is imported into Hyper Study. Then, Hyper Study uses a genetic algorithm to calculate the relevant parameters of the next iteration until the two motors’ final optimization parameters are achieved. Secondly, 2D finite element simulation models of the distributed and centralized winding motors are established using Flux finite element simulation software. The two motors are simulated and analyzed, and the back electromotive force, MTPA curve, output torque, fault behavior, and fault tolerance capability under different fault modes are compared. The results show that the efficiency of the concentrated winding motor is 1.1% higher than that of the distributed winding motor. The concentrated winding motor has a lower proportion of reluctance torque, and its output torque is 1.2 N·m higher than that of the distributed winding motor under open circuit conditions but lower under short circuit conditions. Under inter-turn short circuit, after taking the terminal short circuit (TSC) protection action, the short circuit current of the centralized winding motor is only 80% of that of the distributed winding motor, indicating that the centralized winding motor has more robust fault tolerance performance. Finally, by processing the prototype and building an experimental platform, different load currents are applied to the two motors under healthy operation conditions and fault modes. It is found that the output characteristics and fault tolerance characteristics of the two motors are consistent with the FE simulation results. The experimental results verified the accuracy of the simulation model. The following conclusions can be drawn: (1) Distributed winding motors rely more on reluctance torque, while centralized winding motors rely more on permanent magnet torque. The centralized winding motor has higher efficiency due to much lower end windings, smaller torque ripple, and better performance. (2) Under open circuit conditions, two motors can achieve fault operation through the remaining healthy three-phase windings, and the concentrated winding motor exhibits higher output torque capacity. (3) Under short circuit fault conditions, both motors could effectively suppress the short circuit current after TSC, but the distributed winding motor has higher output torque. (4) Under inter-turn short circuit fault, after adopting TSC protection action, the inter turn short circuit currents of both motors are significantly weakened, and the fault current of the concentrated winding motor is smaller. The fault tolerance performance of the concentrated winding motor is better than that of the distributed winding motor under the inter-turn short circuit. The two multiple 3-phase PMA-SynRMs are good candidates for safety-critical applications. The distributed winding machine is suitable for a relatively high-speed range, while the concentrated winding machine is more suitable for medium and low-speed ranges.
[1] 孙玉华, 赵文祥, 吉敬华, 等. 高转矩性能多相组永磁电机及其关键技术综述[J]. 电工技术学报, 2023, 38(6): 1403-1420. Sun Yuhua, Zhao Wenxiang, Ji Jinghua, et al.Over- view of multi-star multi-phase permanent magnet machines with high torque performance and its key technologies[J]. Transactions of China Electro- technical Society, 2023, 38(6): 1403-1420. [2] 刘国海, 高猛虎, 周华伟, 等. 五相永磁同步电机磁链改进型容错直接转矩控制[J]. 中国电机工程学报, 2019, 39(2): 359-365, 633. Liu Guohai, Gao Menghu, Zhou Huawei, et al.Flux- modification-based fault-tolerant DTC for five-phase PMSM[J]. Proceedings of the CSEE, 2019, 39(2): 359-365, 633. [3] Zhu Z Q, Chu W Q, Guan Y.Quantitative comparison of electromagnetic performance of electrical machines for HEVs/EVs[J]. CES Transactions on Electrical Machines and Systems, 2017, 1(1): 37-47. [4] Wang Bo, Wang Jiabin, Griffo A, et al.Effective turn fault mitigation by creating zero sequence current path for a triple redundant 3×3-phase PMA SynRM[J]. IEEE Transactions on Power Electronics, 2019, 34(11): 11080-11089. [5] Spargo C M, Mecrow B C, Widmer J D, et al.Application of fractional-slot concentrated windings to synchronous reluctance motors[J]. IEEE Transa- ctions on Industry Applications, 2015, 51(2): 1446-1455. [6] Spargo C M, Mecrow B C, Widmer J D.A seminu- merical finite-element postprocessing torque ripple analysis technique for synchronous electric machines utilizing the air-gap maxwell stress tensor[J]. IEEE Transactions on Magnetics, 2014, 50(5): 1-9. [7] Chen Xiao, Wang Jiabin.Magnetomotive force harmonic reduction techniques for fractional-slot non- overlapping winding configurations in permanent- magnet synchronous machines[J]. Chinese Journal of Electrical Engineering, 2017, 3(2): 102-113. [8] Chen Xiao, Wang Jiabin, Patel V I, et al.A nine- phase 18-slot 14-pole interior permanent magnet machine with low space harmonics for electric vehicle applications[J]. IEEE Transactions on Energy Con- version, 2016, 31(3): 860-871. [9] Wang Bo, Wang Jiabin, Griffo A, et al.Experimental assessments of a triple redundant nine-phase fault- tolerant PMA SynRM drive[J]. IEEE Transactions on Industrial Electronics, 2019, 66(1): 772-783. [10] Wang Bo, Hu Jiapeng, Wang Guanghui, et al.A novel stator turn fault detection technique by using equivalent high frequency impedance[J]. IEEE Access, 2020, 8: 130540-130550. [11] Chen Liang, Chen Xiao, Wang Jiabin, et al.A computationally efficient multi-physics optimization technique for permanent magnet machines in electric vehicle traction applications[C]//2015 IEEE Inter- national Electric Machines & Drives Conference (IEMDC), Coeur d'Alene, ID, USA, 2016: 1644-1650. [12] 符荣, 窦满峰. 电动汽车驱动用内置式永磁同步电机直交轴电感参数计算与实验研究[J]. 电工技术学报, 2014, 29(11): 30-37. Fu Rong, Dou Manfeng.D-axis and Q-axis inductance calculation and experimental research on interior permanent magnet synchronous motors for EV[J]. Transactions of China Electrotechnical Society, 2014, 29(11): 30-37. [13] 寇宝泉, 葛庆稳, 张浩泉, 等. 双边错位高速永磁直线同步电机的设计与分析[J]. 电工技术学报, 2021, 36(6): 1149-1158. Kou Baoquan, Ge Qingwen, Zhang Haoquan, et al.Design and analysis of double-sided dislocated high speed permanent magnet linear synchronous motors[J]. Transactions of China Electrotechnical Society, 2021, 36(6): 1149-1158. [14] 王瑾, 李岩, 于占洋, 等. 永磁同步磁阻电动机全负载区域功率因数特性分析[J]. 电工技术学报, 2021, 36(增刊2): 451-459. Wang Jin, Li Yan, Yu Zhanyang, et al.Analysis of power factor characteristics of permanent magnet synchronous reluctance motor in whole load range[J]. Transactions of China Electrotechnical Society, 2021, 36(S2): 451-459. [15] 魏艺涵, 罗响, 朱莉, 等. 基于比例谐振控制器的高凸极率永磁同步电机电流谐波抑制策略研究[J]. 中国电机工程学报, 2021, 41(7): 2526-2538. Wei Yihan, Luo Xiang, Zhu Li, et al.Research on current harmonic suppression strategy of high saliency ratio permanent magnet synchronous motor based on proportional resonance controller[J]. Pro- ceedings of the CSEE, 2021, 41(7): 2526-2538. [16] 鲍晓华, 明帅, 陈国玮, 等. 变频驱动下双斜槽转子感应电机径向电磁力特性分析[J]. 电工技术学报, 2023, 38(10): 2613-2624. Bao Xiaohua, Ming Shuai, Chen Guowei, et al.Analysis of radial electromagnetic force characteri- stics of inverter drive double skewed rotor induction motor[J]. Transactions of China Electrotechnical Society, 2023, 38(10): 2613-2624. [17] Wang Bo, Wang Jiabin, Griffo A, et al.Investigation into fault-tolerant capability of a triple redundant PMA SynRM drive[J]. IEEE Transactions on Power Electronics, 2019, 34(2): 1611-1621. [18] Shi Yanwen, Wang Jiabin, Wang Bo.Electromagnetic- thermal coupled simulation under various fault con- ditions of a triple redundant 9-phase PMASynRM[J]. IEEE Transactions on Industry Applications, 2020, 56(1): 128-137.