微型电动汽车热泵空调系统设计与试验研究

Design and performance experimental research of micro-electric vehicle heat pump air-conditioning system

为了提高某微型电动汽车有效续航里程,对其原有空调系统及换热器进行了改进设计与研究,新热泵空调系统采用4个电磁阀对其冷暖模式进行切换,通过焓差室对换热器和系统的性能进行了测试。首先比较了两种不同流程布置室外微通道换热器的换热能力;进而分别将原空调系统换热器和所设计换热器应用于该热泵空调系统,试验研究了压缩机转速和环境温度对两系统制热/制冷性能的影响。结果表明,2流程换热器压降较小、换热能力较强,优于3流程换热器。在制冷模式下两系统性能相近,而在制热模式下新换热器系统与原换热器系统相比其COP最大提升约75%,制热量最大提升约160%,出风温度最大增加约8.2℃,且能满足微型电动汽车在冬季工况和夏季工况下的热需求。

In order to improve the effective cruising mileage of a micro-electric vehicle,improved design and research was conducted on its original air conditioning system and heat exchanger.The new heat pump air-conditioning system uses four solenoid valves to convert its cooling and heating modes,and the performance of the heat exchanger and system was tested through the enthalpy difference room.First,the heat exchange capacity of outdoor micro-channel heat exchangers arranged for two different processes was compared.Furthermore,the original air-conditioning system heat exchanger and the designed heat exchanger were respectively applied to the heat pump air-conditioning system,and the effects of compressor speed and ambient temperature on the heating/cooling performance of the two systems were experimentally studied.The results show that the heat exchange capacities and pressure drop of the 2nd process are better compared with 3rd process.The performance of the designed heat pump system is similar to that of the heat pump system using the original heat exchanger under the cooling mode.In the heating mode,the corresponding COP is increased by about 75%,heat capacity is increased by about 160%,and air outlet temperature is increased by about 8.2℃maximally.The designed heat pump air-conditioning system and heat exchangers can meet the heat demand of micro-electric vehicle under different working conditions.