谢兴景

摘 要：比亚迪秦是混合动力的典型代表。该车装配了双压缩机空调制冷系统，该系统也是高压电池组冷却系统的重要组成部分。由于增加了电动压缩机、电磁膨胀阀、单向阀、高压电池组冷却管路和装置，因此，该车的空调系统制冷异常的故障的概率也会增加，有典型代表性。本文通过分析企业维修案例，结合比亚迪秦双擎轿车的技术特点分析混合动力轿车空调系统制冷异常的故障，对混合动力汽车和纯电动汽车的空调系统的研究具有一定的价值。

关键词：HV混合动力 电动变频缩机 电磁膨胀阀 HV变频器总成 BMS-电磁管理系统

BYD Qin Shuangqing Air Conditioning System Refrigeration Abnormal Failure

Xie Xingjing

Abstract：BYD Qin is a typical representative of hybrid power. The car is equipped with a dual-compressor air-conditioning refrigeration system， which is also an important part of the high-pressure battery pack cooling system. Due to the addition of electric compressors， electromagnetic expansion valves， one-way valves， high-pressure battery pack cooling pipelines and devices， the probability of abnormal refrigeration failures in the car's air-conditioning system will also increase， which is typical. This article analyzes enterprise maintenance cases， combined with the technical characteristics of BYD Qin Shuangqing car to analyze the abnormal refrigeration failure of the hybrid car air-conditioning system， which has a certain value for the research of the air-conditioning system of hybrid electric vehicles and pure electric vehicles.

Key words：HV hybrid power， electric frequency conversion compressor， electromagnetic expansion valve， HV frequency converter assembly， BMS-electromagnetic management system

1 比亚迪秦双擎进厂修复后产生空调故障

故障车辆冷凝器龙门架行驶过程中剐蹭向后溃退挤压了空调压缩机的高压管接头。剐蹭久了，冷凝器与空调高压管最后被磨蹭穿，制冷剂泄露，冷凝水箱也漏水了。

维修技师更换了冷凝水箱的龙门架，更换了冷凝水箱，更换了破损的制冷管路，并给空调制冷系统补充雪种，对空调系统进行抽真空准备加注制冷剂。抽完真空后，加注制冷剂时空调系统就出现了一连串的故障现象。最后该车辆故障排除经历了两个阶段才把空调系统修复。

2 双压缩机空调系统的故障诊断排除过程

2.1 维修第一阶段：诊断排除空调机械压缩机不工作故障

（1）故障现象

更换高低压制冷管和冷凝水箱。抽真空加注制冷剂，真空吸入一瓶350g的制冷剂后，起动发动机启动空调，从低压侧进行加注，发现无法加注，鼓风机工作，空调无冷风。……