大功率低速直驱永磁电动机动态转矩的时步有限元分析

低速直驱电动机具有极数多、每极每相槽数少的特点,由此产生的谐波对转矩特性影响很大.以36槽30极315 kW的低速永磁同步电动机为例,对其槽极配合和绕组系数进行了理论分析,然后采用时步有限元法对起动过程及稳态进行计算分析,获得考虑谐波影响的转矩特性,进而重点研究气隙大小及转子极靴部位开槽数对电机转矩的影响.结果可为进一步研制低速直驱永磁电机提供理论及技术支持.

Dynamic Torque Calculation on the High-power Low-speed Direct Drive PM Motor Based on Time-step FEM

Since the low-speed direct drive motor has more poles and less number of slots per pole and per phase,the harmonic field has a significant influence on the torque characteristics.Taking a 315 kW low speed permanent magnet(PM) motor with 36 slots 30 poles as an example,the theoretical analysis on the combination of the slots and poles and the winding coefficient are carried out.Then,the dynamic torque characteristics during the starting processes,as well as,the torque in stable state are calculated by means of time-stepping finite element method.Further more,the influences of the air-gap length and the number of slot on rotor pole shoe on the torque are studied especially.The results can provide the theoretical and technological supports for further development of the low-speed direct drive PM motors.