为了满足环境保护的需要，紧跟电动汽车发展潮流，在传统燃油车空调系统的基础上开发了一套二氧化碳(CO2)电动汽车空调系统，在标准汽车空调性能实验台上研究了不同运行参数对其性能的影响和CO2电动汽车空调的内在规律.结果表明：所开发的CO2系统在标准工况下与如今仍在普遍使用的传统制冷剂R134a系统性能相当；在研究的所有运行参数中，室外温度对系统性能的影响最大，高温下性能衰减明显，采用电动压缩机可以满足车辆的实际车冷量需求，而现有的CO2电动压缩机排气压力和排气温度的限制致使系统性能在一些恶劣工况下无法达到最优，因此系统性能仍有较大的提升空间；在相同的换热面积内，气冷器出口制冷剂与环境温差每下降 1℃，系统能效比(COP)可以提升2%～5%，同时系统最优高压得到降低，蒸发温度每提升5℃，系统COP可以提升15%左右.
In order to meet the needs of environmental protection and closely follow the development trend of electric vehicles, a CO2 air conditioning system for electric vehicle was developed based on the traditional air conditioning system of vehicle, the effects of different operating parameters on its performance were studied on the standard mobile air conditioning bench in order to see the new rules and provide guidance for the optimization of key components. Results show that the performance of the developed CO2 system can match the traditional refrigerant R134a, which is still commonly used. Among all the operating parameters, it was found that the outdoor temperature has the greatest impact on the system performance, and the performance decay is obvious under high temperature. The electric compressor can meet the cooling capacity needs of a real car, in some harsh conditions, system performance can not be optimal because of the discharge pressure and temperature limits of the existing CO2 electric compressor, so there is much space for system performance improvement by optimizing the compressor. If the temperature difference between the refrigerant and environment at the outlet of gas cooler can drop by 1℃ for the same heat exchange area, the COP of the system can be increased by 2%～5%, the optimal high pressure of the system can be reduced as well, if the evaporation temperature can increase by 5℃, the COP of the system can be increased by 15%.
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