双向MEMS膨胀阀及其在电动大巴热泵系统中的应用

Application of two-way MEMS expansion valve to heat pump system of electric bus

为克服步进电机式的电子膨胀阀在汽车空调上易失步问题,以及热力膨胀阀热惰性不适应变频压缩机的缺点,同时为了满足新能源汽车热泵空调的要求,本文提出一种基于热驱动的双向MEMS膨胀阀,MEMS膨胀阀非步进电机式的驱动方式确保其不会受到汽车振动的影响,同时其线性快速响应速度能够解决热力膨胀阀热惰性的缺点。采用空调的测试标准,利用一台电动大巴热泵系统进行热力膨胀阀和MEMS膨胀阀的对比试验,结果显示,采用MEMS膨胀阀的电动大巴热泵系统能效提升14.7%,同时完成装车试验中行驶200 km无故障的要求。

In order to solve the issue of losing steps of electronic expansion valve which driven by stepper motor used in the vehicle air-conditioning, overcome the non-applicability of thermostatic expansion valve in frequency-conversion compressor because of thermal in-ertia ,and meet the requirement of heat pump system of new energy vehicles, one thermal driven two-way MEMS expansion valve is put forward. The MEMS expansion valve isnt inHuenced by the vehicle vibration because it,s not driven by stepping motor. Besides,the fast liner respond speed can overcome the thermal inertia of thermostatic expansion valve. According to the test standard on air-conditioning, the contrast tests between MEMS ex-pansion valve and thermostatic expansion valve are conducted using the heat pump system of one electric bus. The results show that the energy efficiency of the heat pump system of electric bus using MEMS expansion valve can be improved by 14.7% ; during loading test, the heat pump system of electric bus is trouble-free after driving 200 km.