极靴式永磁同步电机径向气隙磁密分析

Analysis of Radial Air-gap Magnetic Density of Permanent Magnet Synchronous Motor With Pole-shoe

针对表贴式永磁同步电机空载径向气隙磁密波形正弦性差,加工复杂结构的永磁钢导致电机成本提高的问题,提出一种表贴式矩形永磁钢加装极靴的新型磁极结构。以标量磁位法为基础,建立了加装极靴后的空载径向气隙磁密解析模型,以一台18极54槽外转子永磁电机为例,通过有限元法验证了解析模型的正确性。此外,基于解析模型研究极靴结构参数对径向气隙磁密的影响规律,获得最优参数匹配。结果表明,加装极靴的永磁同步电机径向磁密幅值和波形正弦化程度明显提高。

Aiming at the problem that the surface-mounted permanent magnet synchronous motor has poor si­nusoidal no-load radial air-gap magnetic density waveform,and the processing of complex structure perma­nent magnet steel leads to an increase in the cost of the motor,a new magnetic pole structure with surface-mounted rectangular permanent magnet steel and pole shoes was proposed.Based on the scalar magnetic po­tential method,an analytical model of the no-load radial air gap magnetic density with pole shoe was estab­lished.Taking an 18-poles and 54-slots external rotor permanent magnet motor as an example,the correct­ness of the analytical model was verified by the finite element method.In addition,based on the analytical model,the influence of the pole shoe structure parameters on the radial air gap magnetic density was studied to obtain the optimal parameter matching.The results show that the radial flux density and waveform sinu­soidal degree of the motor with pole shoes are significantly improved.