针对表贴式永磁电机存在的齿槽转矩问题,提出运用单磁极加长的方法来降低电机齿槽转矩。运用解析法推导出电机单磁极加长后齿槽转矩解析表达式,通过傅里叶分析,得到对电机齿槽转矩具有重要影响的变量B_r(vz)。引入磁极加长系数η,研究如何选取η的数值削弱齿槽转矩。通过有限元仿真验证了所提方法的有效性。结果表明:通过合理选取磁极加长系数,将与齿槽转矩关键谐波分量有关的B_r(vz)削减为零可有效降低电机齿槽转矩。

For the problem of cogging torque existing in surfacemounted permanent magnet (SPM) motor, a method of single magnetic pole lengthening was proposed to reduce the cogging torque. The analytical expression of the cogging torque was derived by the analytic method when the single magnetic pole of the motor was lengthened and the variable B_r(vz) which had an important influence on the cogging torque was obtained through Fourier analysis. The magnetic pole lengthening factor η was introduced and the way to choose the value of η to reduce the cogging torque was studied. The availability of the method was validated by finite element simulation. It was found that the cogging torque of SPM motor could be effectively reduced when the B_r(vz) related to the key harmonic components of the cogging torque was reduce to zero by reasonably selecting the magnetic pole lengthening factor.

TM 351

国家科技支撑计划课题(2015BAG03B00)