电动汽车电池冷却系统的试验研究

Experimental study on battery cooling system of electric vehicle

为将空调系统恰当地应用到电动汽车上,并能够更好地与电池冷却系统匹配,减少其对电池的动力性能和续驶里程的影响,本文搭建空调系统试验平台,对单空调系统(以下用"HVAC"表示)充注量、HVAC和chiller(电池热交换器的简称)组成的双蒸发器系统充注量以及压缩机转速进行试验分析,确定空调系统制冷剂的最佳充注量,选出匹配的压缩机转速。结果表明:单chiller系统运行时,压缩机在较低转速下工作即可满足防冻液侧换热能力的要求;双蒸发器系统运行时,chiller换热比随压缩机转速的增加而增加,且chiller的换热能力始终比HVAC系统中蒸发器换热能力大,可以通过调节热力膨胀阀控制chiller的制冷剂流量,改变系统流量分配,提升HVAC中蒸发器的换热量。

In order to apply the air-conditioning system to the electric vehicle properly,match with the battery cooling system,and reduce the influence of air-conditioning system on the dynamic performance of battery and the travel distance,the test platform of the air-conditioning system is set up. The experimental analysis on the refrigerant charge of single HVAC system,and the refrigerant charge and compressor speed of dual evaporators system composed of HVAC chiller is conducted. The optimal refrigerant charge of the air-conditioning system is obtained,as well as the matched compressor speed. The result shows that when the single chiller system operates,the compressor can meet the requirements of heat transfer at the antifreeze side even under lower speed; when the dual evaporators system operates,the chiller＇s heat transfer ratio increases with the compressor speed increasing,and the heat transfer ability of chiller is better than that of the evaporator in the HVAC all the time. The chiller＇s refrigerant flow could be controlled by the thermal expansion valve,which changes the flow distribution in the system,so as to improve the heat transfer capacity of evaporator in the HVAC.