扇区集中式改进型不等齿多相永磁同步电机分析

为了降低电动汽车用表贴式永磁同步电机(surface mounted permanent magnet synchronous motor,SPMSM)的相间互感,提高其容错性能,提出一种可模块化设计的采用改进不等齿宽定子的扇区集中式分数槽集中绕组(fractional slot concentrated winding,FSCW)定子拓扑结构。在此基础上,推导了这种新拓扑结构仅由定子绕组产生的气隙磁密频谱的可行极槽组合,并对其可选的极槽组合方案进行分析。有限元分析(FEA)证明了这种新型拓扑结构可以有效地减小相间互感,提高输出转矩。通过建立采用这种新型拓扑结构的每相2线圈、每相3线圈、每相4线圈的六相SPMSM模型,比较反电动势(electromotive force,EMF)、转矩脉动、损耗和隔磁性能,得出了每相2、3、4组线圈的扇区集中式改进型不等齿FSCW电机的特性。结果表明,每相偶数组线圈和极数较少的极槽配合方案的转矩波动更低,隔磁性能更好,另外,每相线圈数越多电机的永磁体涡流损耗越低,但定子铁芯损耗越高。

Sector Centralized Fractional Slot Concentrated Winding with Improved Unequal Teeth Width Topology Permanent Magnet Synchronous Motor

To reduce inter-phase mutual-inductance and improve performance of surface mounted permanent magnet motors (SPMSM) for electric vehicle (EV), a novel sector centralized fractional slot concentrated winding (FSCW) with improved unequal teeth width stator topology, which offers potentials of modular design and fault tolerant capability is proposed. Then feasible slot/pole combinations got by spectrum of air gap flux density only produced by stator windings of this new topology are elicited and analyzed for scheme selection. The finite element analysis (FEA) proves that this novel topology can reduce inter-phase mutual-inductance and increase output torque effectively. And this paper goes a step further, two coils per phase, three coils per phase and three phase coils per phase six-phase PMSMs with the novel topology are modeled. Characteristics of the three kinds of PMSMs are obtained through comparing back electromotive force (EMF), torque ripple, losses and flux isolation performance. The results show that the torque fluctuation is lower and the magnetic isolation performance is better in the matching scheme of even array coils and pole grooves with fewer poles per phase. In addition, the more coils per phase, the lower eddy current loss of permanent magnet, but the higher core loss of stator.