电动汽车空调系统中的电子膨胀阀性能研究

Performance Research of Electronic Expansion Valve in Electric Vehicle Air Conditioning System

为了对比研究电子膨胀阀与H型热力膨胀阀对电动汽车空调性能的影响,课题组搭建了电动汽车空调性能试验台。在制冷工况下对采用2种膨胀阀的空调系统进行了变工况、变压缩机转速试验。结果表明:在不同的工况下,采用电子膨胀阀能使空调系统获得更低的出风温度,且在高温工况下,电子膨胀阀有更佳的调节性能;对过热度的控制方面,采用电子膨胀阀过热度稳定更快且波动范围小;系统采用电子膨胀阀时制冷量更大,且环境温度越高对制冷量影响越显著;变压缩机转速下,采用电子膨胀阀的系统制冷量和能效比CCOP均高于采用H型热力膨胀阀的系统,且在低转速时效果更加显著。电子膨胀阀结合变转速压缩机,能够提高系统制冷量和能效比CCOP,使系统更加高效运转。

In order to compare the influence of the electronic expansion valve and the H-type thermal expansion valve on the air conditioning performance of electric vehicles,a test bench for the air conditioning performance of electric vehicles was built.Under refrigeration conditions,the air conditioning system with different expansion valves was tested under variable conditions and variable compressor speed.The result shows that under different working conditions,the use of electronic expansion valve can enable the air conditioning system to obtain lower air output temperature,and under high temperature conditions,the electronic expansion valve shows better regulation performance;for the control of the superheat degree,the superheat degree of the system using electronic expansion valves stabilizes faster with small fluctuation range;when the system uses an electronic expansion valve,the cooling capacity is larger,and the effect on the cooling capacity is more significant with the higher ambient temperature;at variable compressor speed,the system cooling capacity and coefficient of performance(CCOP)of the system using electronic expansion valve are both higher than that using H-type thermal expansion valve,and the effect is more significant at low speed.The combination of electronic expansion valve and variable speed compressor can improve the cooling capacity and CCOP of the system,and make the system operate more efficiently.