双凸极永磁电机的对称化设计

Symmetric design of doubly salient permanent magnet motors

针对永磁双凸极电机存在各相反电势(EMF)不对称和转矩脉动较大的问题,提出2种分别基于不等槽宽和等槽宽设计的新型双凸极永磁(DSPM)电机.该设计方法可以确保电机各相磁路具有相同的磁阻特性,并通过定子绕组的特殊排布以补偿电机自感的变化.通过实现电机各相磁路对称并削弱自感的波动程度,可以有效消除电机各相EMF的不对称以及最大程度削弱转矩脉动.采用有限元时步法对新型电机处于空载和负载条件下的稳态性能进行了比较分析.仿真和实验结果验证了新型DSPM设计方法的有效性.

This paper presents two design approaches for doubly salient permanent magnet （DSPM） motors based on unequal and equal slot width methods respectively, aiming to eliminate the asymmetry of electromotive force （EMF） between phases and minimize the torque ripple. The key is to propose the design criteria that the reluctance of all magnetic paths is the same, and the stator windings can be purposely connected to compensate the variation of self-inductance. Based on these methods, the magnetic characteristics become symmetric, and the variation of self inductance is suppressed. Thus, the asymmetry of EMF between phases can be eliminated and torque ripple can be minimized. By using the time-stepping finite element method, the proposed DSPM motors are quantitatively compared under both no-load and load conditions. Both simulation and experimental results are given to verify the validity of the proposed machine.