轴向磁通轮毂电机热分析及研究

Thermal Analysis and Research of Axial Flux In-wheel Motor

电动汽车用轮毂电机需满足高功率密度和高效率的要求,电机的发热与散热问题直接影响车辆运行的可靠性和稳定性。本文以一台卷绕式非晶合金定子齿无磁轭模块化轴向磁通轮毂电机为分析样机,基于电机电磁损耗理论,建立电机的三维电磁场有限元模型,计算不同工况下电机的电磁损耗。分析定子齿热传导方式,计算各部件等效导热与散热系数,建立电机的三维温度场有限元模型,得出电机温升的幅值与分布。加工样机并搭建实验平台,通过热电偶和红外热像仪测试电机不同位置处的温度,与计算结果相符,验证了有限元模型的有效性。本文所提出样机的热特性满足电动汽车要求,可以为新型轴向磁通轮毂电机热设计提供参考。

The in-wheel motor for electric vehicles needs to meet the requirements of high power density and efficiency.The heating and heat dissipation of the motor has an impact on the reliability and stability of the vehicle operation.In this paper,an yokeless and segmented armature axial flux in-wheel motor with wound amorphous alloy stator tooth is used as an analysis prototype.Based on the theory of electromagnetic loss,a three-dimensional electromagnetic field finite element model of the motor is established.The electromagnetic losses of the motor under different working conditions are calculated.The heat conduction method of the stator teeth is analyzed.The equivalent thermal conductivity and heat dissipation coefficient of each component are calculated,a three-dimensional temperature field finite element model of the motor is established.the amplitude and distribution of the motor temperature rise are obtained.The prototype is manufactured and the experimental platform is built.The temperature at different positions of the motor is measured by thermocouples and infrared cameras,which is consistent with the calculation results.The effectiveness of the finite element model is verified.The thermal characteristics of the prototype proposed in this paper meet the requirements of electric vehicles and can provide a reference for the thermal design of novel axial flux in-wheel motors.