永磁同步电机转子永磁体内涡流损耗密度的计算

针对钕铁硼永磁材料提出了一个计算永磁同步电机转子永磁体内涡流损耗密度的公式.通过三维电磁场有限元方法，求解了电机内的磁场并计算出了永磁体内的涡流损耗，验证了公式的正确性.在分析计算中考虑了电机复杂三维结构的特点，同时根据对称性，取电机的一个极范围作为分析的简化模型.为了能很好地分析和画出精确的涡流波形，对每一个周期取100个时间子步作瞬态分析，并且在划分有限元单元时考虑了磁场的透入深度.最后根据计算结果的比较得出影响永磁体内涡流损耗的因素.

Calculation of eddy current loss density distribution in permanent magnet of PMSM

For NdFeB material,a formula is proposed to calculate eddy current loss density distribution in the permanent magnet of PMSM.The magnetic field of motor and the eddy current loss in PM are both solved based on FEM for three-dimensional electric magnetic field.One pole of motor is chosen as the simplified analyzing model according to symmetry with the complicated three-dimensional feature of PMSM.Every cycle is divided into 100 time steps to make instantaneous analysis so that desirable analysis and precise waveform of eddy current can be acquired.Also,skin depth of magnetic field is taken into account when finite elements are divided.As a result,the influencing factor of eddy current loss is obtained according to the calculation and the formula is verified.