电动汽车轮毂电机磁—热双向耦合研究

Magnetic-thermal bidirectional coupling of in-wheel motor for electric vehicle

针对电动汽车轮毂电机热负荷大、温升显著等问题,对轮毂电机的电磁场和温度场进行了仿真研究。首先,建立了表贴式外转子轮毂电机的几何模型;基于电磁场有限元模型和等效热网络模型,采用电磁—热双向耦合,实现了两物理场间损耗与温度数据的交换,准确计算出了电机损耗和温升数值;通过损耗和机壳的温升试验值,验证了电磁—热双向耦合仿真结果的合理性;采用该方法参数化分析了轮毂电机的结构。研究结果表明:气隙长度增加,定子铁心和绕组温度均随之上升;随着定子槽深度的增加,定子铁芯的温度呈先上升后下降的趋势。

Aiming at the problems such as large thermal load and significant temperature rise of electric vehicle in-wheel motor, the electromagnetic field and temperature field of the in-wheel motor was simulated.Firstly, a geometric model of the external rotor in-wheel motor was established.Based on the finite element model of electromagnetic field and the equivalent thermal network model, the magnetic- thermal bidirectional coupling was used to realize the exchange of two physical fields loss and temperature data, and finally accurately calculated the motor loss and temperature rise.The simulation results of the magnetic-thermal bidirectional coupling were verified by the loss and temperature rise test.Finally, the method was used to parameterize and analyze the in-wheel motor structure.The results show that the temperature of stator core and winding increases with the increase of air-gap length.As the depth of stator groove increases, the stator core temperature increases first and then decreases.