The cooling effect of oil cooling method on electric vehicle motors with hairpin winding is analyzed. A 160 kW motor being developed by a commercial vehicle company is applied. Firstly, the flow field of oil was analyzed. In the crown part, 96% of the oil flowed; in the welded part, 90% of the oil flowed. Secondly, an analysis of the heat transfer in the coil and stator was performed. The welded part of the coil exhibited an average temperature 4% higher than that of the crown part. Finally, the parametric study was conducted to understand the effect of the temperature and flow rate of the oil on the temperature distributions of the motor. As the flow rate increases, the maximum temperature decreases. However, there is not a big difference at more than 0.8 LPM/LPM. The results provide important information for understanding the effect of a motor using oil cooling.

分析了油冷却方法对发夹式绕组电动汽车的冷却效果。使用由商用车公司开发的160 kW电动机。首先，分析了油的流场。在表冠部分，有96％的油流过。在焊接部位，有90％的机油流过。其次，对线圈和定子中的热传递进行了分析。线圈的焊接部分的平均温度比胎冠部分的平均温度高4％。最后，进行了参数研究，以了解油的温度和流速对电机温度分布的影响。随着流量增加，最高温度降低。但是，大于0.8 LPM / LPM并没有太大的区别。