无刷直流电动机瞬态电磁-温度耦合场分析

Transient Coupled Electro-Magnetic Thermal Analysis of a Brushless DC Motor

航空用永磁无刷直流电动机通常具有高转速、小体积、大功率密度的特点,因此该类电机的发热问题较为突出。为了对永磁无刷直流电动机温度场进行准确仿真,必须考虑电机内电磁场与热场的耦合效应。采用二维时步有限元法对一台4极3相30 kW表贴式永磁无刷直流电动机的温度场进行了分析计算。各物理场之间的耦合是通过损耗计算及材料特性随温度变化而实现的。计算结果和实测结果进行了分析比较,验证了模型的有效性。

Permanent magnet brushless DC motors used in aerospace generally feature high-speed,small volume and high power density.This means that the thermal design of those motors is crucial.In order to obtain an accurate thermal field simulation of a permanent magnet brushless DC motor,both electromagnetic and thermal fields are expected to be calculated in a coupled simulation.In this paper,the computation based on FEM method was applied to a four-pole three-phase 30 kW PM brushless DC motor.The coupling of the fields was performed via a detailed loss calculation and the temperature dependence of the permanent magnets and conductive materials.Simulation results were presented,and,to validate the model,the results were compared with experimental data.