摘要:转矩波动是内置式永磁同步电机的主要缺点之一,而凸极转矩在转矩波动中占有一定比例。首先给出了包含凸极转矩的内置式永磁同步电机的转矩波动计算公式;其次,通过有限元法计算了内置式永磁同步电机不同转子结构情况下空载反电动势谐波畸变率(THD)与电机电磁转矩波动的关系,揭示两者不成比例;最后利用保存磁导率法和傅里叶分解法将永磁转矩与磁阻转矩进行分离并进行了对比,得出两者在电磁转矩中所占的比例,同时计算了纹波转矩和凸极转矩的波动情况,得到永磁转矩产生的纹波转矩与EMF的THD有关,而磁阻转矩产生的凸极转矩与EMF的THD无关,为降低内置式永磁同步电机转矩波动提供了理论依据。 关键词:转矩波动;凸极转矩;反电动势谐波畸变率;内置式永磁同步电机
Abstract: Torque ripple is one of the main disadvantages of the interior permanent magnet synchronous motor. The salientpole torque plays a certain proportion in the torque ripple. Firstly, the calculation formula of torque ripple for interior permanent magnet synchronous motor including salientpole torque was presented. Secondly, according to the finite element method, the relationship between the harmonic distortion rate (THD) of the noload back electromotive force and torque ripple of the interior permanent magnet synchronous motor with different rotor structure was calculated. There is no proportional relationship between the two. Finally, the permanent magnet torque and the reluctance torque were separated by the method of keeping the magnetic permeability, the proportion of the two in electromagnetic torque was obtained. At the same time, the fluctuation of the permanent magnet torque and reluctance torque were calculated. The ripple torque generated by the permanent magnet torque is related to the THD of EMF, the salientpole torque generated by the reluctance torque is independent of THD of EMF. The theoretical basis was provided for reducing the torque ripple of the interior permanent magnet synchronous motor. Key words: torque ripple; salientpole torque; EMFTHD; interior PMSM
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