电动汽车用高功率密度感应电机的设计与研究

Design and research on high power density induction motor in electric vehicle

针对目前永磁材料价格大幅度上涨,永磁电机和电动汽车动力系统成本增加的问题,给出了一个高功率密度感应电机方案,并介绍了方案的设计过程和感应电机提高功率密度的方法。运用有限元法计算了电机的输出能力、温升和转子强度等关键性能。通过参数化扫描电机的气隙长度和铁心长度,总结了它们对电机性能的影响。计算了电机额定运行时的损耗分布,并设计了机壳水冷回路,通过电磁场和温度场耦合计算,得出了电机的温度分布规律。最后,为了保证电机转子高速运行时的可靠性,计算了转子形变趋势和应力分布,得到了应力随转速的变化规律。结果表明,该电机具有良好的输出性能,并且散热能力好,可以长时间运行。

In this paper,a high power density induction motor scheme is proposed,and the design process of the scheme and the method of improving the power density of induction motor are introduced,with the price of permanent magnet material increasing greatly and the cost of permanent magnet motor and electric vehicle power system increasing.The output performance,temperature and rotor strength of the motor were calculated by the finite element method.The influences of air gap length and core length on the performance of the motor were summarized.The loss distribution of the motor under rated operation was calculated,and the shell water-cooling circuit was designed.The temperature distribution law of the motor was obtained through the coupling calculation of electromagnetic field and temperature field.Finally,in order to ensure the reliability of the motor rotor under high-speed operation,the deformation trend and stress distribution of the rotor were calculated,and the change rule of the stress with the rotation speed was obtained.The results show that the motor has good output performance,good heat dissipation and can run for a long time.