中文摘要：

对广州地铁一号线2930车的DC／AC所发生的严重故障，首先，通过硬件更换排除30A车DC／AC的硬件故障；然后，利用KLIP模块故障报警信号是低电平有效的原理，通过对调KLIP模块诊断反馈线路排除诊断系统的故障；再根据DC／AC内电锍不平衡，推断故障为30A车DC／AC所带的两台空调压缩机负载所引起；最后，通过单独测试两台压缩机，确定故障为30B车2位端空调压缩机的电机三相不平衡而导致，从而排除2930车的DC／AC所发生的严重故障，使2930车重新得以正常运行。

英文摘要：

In this paper the DC/AC serious failure of No.2930 car of line one subway of Guangzhou is analyzed. First of all, exclude hardware fault by exchanging hardware of the DC/AC. Secondly, exelude diagnosis system fault by replace the KLIP module feedback, At last according to the imbalance of dynarnie current we find out the boot fault cause by the imbalance of the air conditioner compressor motor which is one of the load of DC/AC for 30A car. We solve the problem and recover No. 2930 car.