针对家用高压清洗机风冷串激电机定子绕组温升过高的问题，以一台HC8840F单相风冷串激电机为研究对象，建立电机全域三维流固耦合传热模型。在此基础上，使用流固耦合传热计算方法模拟获得串激电机内部流场及温度场，并搭建试验平台，通过不同工况下样机定子绕组的温升试验验证串激电机三维流固耦合传热模型的合理性。在模型验证的基础上，分析了风冷系统流场和温度场的分布规律，为结构优化设计指导方向。此外，从降耗设计的角度出发，研究了风冷系统中后端离心风轮对电机内流场与温度场的影响。仿真结果表明，内部导风轮的设置改善了气流流动，能使定子绕组平均温升降低了3.3 ℃。

The air-cooled universal motor used in the household high pressure washer has a problem of overheating in the stator winding. A three-dimensional fluid-solid coupling heat transfer model of the motor is built using an example of an HC8840F air-cooled single-phase series motor. On this foundation, the internal flow field and the temperature field of the series motor are simulated using the fluid-solid coupling heat transfer calculation method. To confirm the validity of the three-dimensional fluid-solid coupling heat transfer model of the universal motor, the stator winding of the motor is subjected to temperature rise test under various working conditions. On this basis, the guidelines for the design of structural optimization are provided. From the perspective of consumption reduction design, the impact of rear fan on the internal flow field and the temperature field of the motor is analysed. The findings demonstrate that the internal fan alters the airflow and make the average temperature of the stator winding decrease by 3.3 ℃.