表贴式永磁无刷电机直接解析计算方法

Exact Analytical Method for Surface-Mounted Permanent-Magnet Brushless Motors

采用直接解析法计算表贴式永磁无刷电机空载气隙主磁场、齿槽转矩和反电动势。求解场域划分为气隙、永磁体和槽区域,三个子区域的拉普拉斯方程或泊松方程通过交界条件建立联系,然后采用解析法直接求解。计算中确切计及了实际槽深和槽间距离。开槽气隙主磁场、齿槽转矩和反电动势解析计算波形分别与二维有限元法计算结果和实验波形作比较,比较结果较为一致,证明了本文方法的正确性和有效性。

The exact analytical method is applied to compute air-gap main magnetic field distribution, cogging torque and electromotive force （EMF） in surface-mounted permanent-magnet （PM） motors. The solution regions are divided into air-gap domain, permanent magnet domain and slot domains. The Laplace＇s or Poisson＇s equations of the sub-domains are solved by the exact analytical method and the solutions are obtained using boundary and interface conditions. The actual depth of slot and distance between slots are taken into account in the computation. Air-gap magnetic field distributions, cogging torque and EMF waveform computed with the proposed analytical method are respectively compared with those issued from two-dimensional finite-element analysis and experimental waveforms, the comparison results are consistent and show the correctness and effectiveness of the proposed analytical method.