一起发电厂直流系统接地故障的查找及处理

Search and Process of a DC System Grounding Fault in Power Plant

介绍了一起发电厂输煤110 V直流系统负极接地的故障。通过拉路法查出故障接地点,判断脱硫湿式球磨机B开关及5C皮带机开关控制回路存在接地点。由于是负极两点接地同时存在,对直流系统接地采用拉路法查找带来难度,分析了处理过程,更改拉路法方案,找出故障原因并提出改进措施,为用拉路法查找直流系统短接地提供了参考。

Introduction was made to a power failure of 110V DC system negative electrode grounding in the process of transporting coal in power plant. There existed grounding points in the control circuits of desulfurized wet ball mill B and 5C belt machine switches. Fault grounding points were found by the pulling path method. Because two negative electrode grounding points existed at the same time, it was not easy for the pulling path method to search grounding points in the DC system. This paper analyzed the process carefully and adopted the pulling path method to ifnd the fault reasons, raising some improved measures, which provides references for searching grounding points in the DC system.