Abstract: Based on an electric vehicle, the active heating function of the e-motor and it’s total vehicle thermal management control system are developed, and in order to know the real situation of performance of the active heating function, the low-temperature direct current (DC) charging and air conditioning (A/C) heating tests are carried out respectively. The verification results show that the e-motor can be used as a heat source to supply heat to the battery and A/C under the condition of parking and driving. The e-motor can output about 2 kW of heat in the condition of parking, and the heating efficiency (heat transferred to coolant ÷ power loss of the e-motor) is only about 70%. When driving at low speed (32 km/h), although the heating capacity of the motor is increased to 2.4 kW, the heating efficiency drops to 64% affected by the heat dissipation of the shell. After the vehicle speed rises to 80 km/h, the average heating power is about 3 kW, and the heating efficiency is affected by factors such as transmission loss, resulting in distortion of calculation results. Due to the low real efficiency of the active heating of the e-motor, the vehicle control system needs to limit the application scenario and the duration of this function, which not only needs to meet the rapid heating demand under a few extremely low-temperature working conditions, but also prevents excessive energy consumption.

Key words: Electric vehicle; Vehicle e-motor; Active heating; Thermal management system

摘要： 基于某款电动汽车开发了电机主动加热功能及整车热管理控制系统，并分别通过低温 快充、空调采暖试验对电机主动加热功能进行性能测试。测试结果表明，电机在停车、行驶 状态下均可作为热源为电池和空调供热，停车状态电机可输出热量约 2 kW，加热效率（冷却 液吸收热量÷电机损耗功率）仅约 70%；低速行车时（32 km/h），虽然电机加热能力提升至 2.4 kW，但受壳体散热影响，加热效率降至 64%；车速提升至 80 km/h，平均加热功率约 3 kW， 加热效率受传动损耗等因素影响导致计算结果失真。由于电机主动加热的真实效率较低，整 车控制系统需限制该功能的应用场景和开启时间，在满足少数、极低温工况下快速升温需求 的前提下，防止系统能耗过高。

关键词: 电动汽车；汽车电机；主动加热；热管理系统