组合磁极削弱永磁同步电动机转矩脉动方法研究

Research of modular pole on the reduction of torque ripple of permanent magnet synchronous motor

针对永磁同步电动机的转矩脉动削弱问题,研究了组合永磁磁极的转矩脉动削弱方法。组合磁极由两种性能不同的永磁材料组成,通过合理选择永磁材料与极弧宽度组合,可削弱气隙磁密和反电动势谐波,进而削弱转矩脉动。采用解析法计算组合磁极产生的气隙磁密和反电动势,研究组合磁极的极弧宽度变化对反电动势的谐波的影响,以总谐波失真最小为标准,得到极弧宽度组合。有限元计算结果表明,采用极弧宽度组合时,反电动势谐波和永磁电机的转矩脉动都得到了很好地削弱。

In order to reduce the torque ripple of permanent magnet synchronous motor （ PMSM ）, the method of modular pole is studied in this paper. The air-gap flux density and phase back EMF with mod- ular pole were calculated with analytical method. Based on the analytical expression, the effect of pole- arc width of modular pole on the harmonics of back EMF was studied. The total harmonic distortion （THD） was taken as a standard, and the optimal pole-arc combination was obtained. The calculated re- suits of finite element method （FEM） verify that the harmonics of back EMF and torque ripple can be re- duced with modular pole.