Abstract: Considering that external rotor in-wheel motors adopted different cooling methods to cause different temperature rise distribution and had different effects on the motor deformation, an external rotor in-wheel motor model was established to analyze the magnetic field of the motor. By using the loss in the motor as a heat source, the coupling analysis of the motor temperature field and temperature stress was carried out, so as to study the temperature rise and deformation distribution of each component of the external rotor in-wheel motor when different cooling methods were used. Based on this, the deformation difference between single motor and in-wheel motor was compared. By comparing the experimental data with the finite element data, the maximum error of the motor component’s temperature is 6.6%, which verified the correctness of the proposed model of the external rotor in-wheel motor. The results show that different cooling methods have different effects on the temperature distribution and the deformation of the motor. The deformation results of the single motor and the in-wheel motor are different under the same cooling condition. This research provides a certain reference value for motor performance, life and safety.

Key words: vehicle engineering; in-wheel motor; cooling method; safety; temperature field; temperature stress

摘要： 考虑到外转子轮毂电机采用不同冷却方式会产生不同的温升分布，并且对电机形变产生不同影响。建立外转子轮毂电机模型进行电机磁场分析，通过将电机中损耗作为热源，进行电机温度场与温度应力耦合分析，研究外转子轮毂电机在采用不同冷却方式时各部件温升以及形变分布情况；在此基础上，对比单电机与轮毂电机的形变差异；通过实验数据与有限元数据对比，电机部件温度最大误差为6.6%，验证了外转子轮毂电机模型建立的正确性。结果表明：不同冷却方式对电机温度分布情况以及电机形变影响不同，单电机与轮毂电机在相同冷却条件下形变结果不同。该研究为电机性能、寿命以及安全性提供一定参考价值。

关键词: 车辆工程；轮毂电机;冷却方式;安全性;温度场;温度应力