电动汽车冷却系统设计及电机最优冷却温度控制

Motor cooling system design and optimal cooling temperature control of electric vehicle

根据各部件的温度特点设计电动汽车冷却回路,分析无刷永磁同步电机的发热原理;基于各零部件等效热容得到热量从产生到散发转移的理论公式。以总电耗最低为评价指标寻找某一环境温度下的最佳冷却水温度,据此开发出电动车最优冷却水温度控制策略。与水泵定排量控制相比,最优冷却水温度控制策略对应的整车效率由60.5%提高到66.1%。

The cooling circuits of Electric-vehicles （EVs） are designed according to the temperature characteristics of all parts. The heating principle of the brushless permanent magnet synchronous electric motor is analyzed. The theoretical heat transfer equation from generation to dissipation is derived based on the equivalent heat capacity of the parts. The minimum power consumption is taken as the evaluation index to search for the optimum cooling temperature under certain environment temperature. Based on this the optimum cooling temperature control strategy is built. Compared with pump fixed-displacement control, the vehicle efficiency with the proposed optimum cooling temperature control strategy is improved from 60. 5% to 66.1%.