环境温度对电动汽车热泵空调系统性能的影响

针对电动汽车冬天取暖能耗较高,设计了基于蒸气压缩循环的热泵空调试验系统,研究了制热模式下不同的环境温度和压缩机转速对车室内平均温度、高压管路内部工质的温度和压力、系统能效比(COP, Coefficient of Performance)等参数的影响.试验结果表明,当环境温度和压缩机的转速较高时,压缩机出口、车室内换热器出口处工质的温度和压力值较大,车室内平均温度的上升速度越快,达到舒适温度所需的时间越短.在压缩机转速相同时,环境温度越高,系统的COP值越大.

Effects of different ambient temperatures on performance of electric vehicles' heat pump air conditioning

A heat pump air conditioning experimental system for electric vehicles based on the vapor-compression cycle was designed because much energy was consumed for the electric vehicle air conditioning under the heating mode when the ambient temperature was low. The refrigerant temperature and pressure in the high-pressure pipeline, the rate of temperature rising in the cab and the coefficient of performance (COP) for the air conditioning system were studied in the heating mode under different ambient temperatures and different compressor speeds. The test results indicate that, when the ambient temperature and the compressor speeds are higher, the temperature and pressure of the refrigerant at the compressor outlet and the heat exchanger outlet are higher, and the average temperature increases faster and the time reached to the comfort temperature is shorter in the cab. When the ambient temperature is higher in case that the compressor kept the same speed,the COP is greater.