基于消弧消谐柜自身故障引发的接地事故分析及改进措施

Analysis of Grounding Accident Caused by the Fault of Arc Extinguishing and Harmonic Elimination Cabinet and its improvement measures

某变电站35 kV不接地系统采用单母分段接线,每段母线配置一面消弧消谐柜,因设计阶段消弧消谐柜电源侧仅配备隔离开关。因未配置断路器,当其自身发生故障时,无法及时有效切除故障点,仅能通过母线全停方式解决问题,造成电力用户被迫停产,产生较大经济损失。尤其单相接地故障,因消弧消谐柜属于全封闭式柜体,接地点查找难度大,大大增加了事故处理时间及难度;又因母线停送电操作复杂,进一步增加了系统接地时间,给系统安全稳定运行造成隐患。针对此问题,提出了消弧消谐自身单相接地故障的查找方法、预防及改进措施。

A substation’s 35 kV ungrounded system used a single bus scheme, each section of the bus was equipped with an arc extinguishing and harmonic elimination cabinet. Because the power side of the cabinet was equipped only with isolation switches instead of circuit breakers during the design phase, when its own fault occurs, the fault point could not be dealt with in time, and the bus had to be full cut in order to solve the problem, resulting in power users were forced to stop production with large economic losses. Especially when it comes to single-phase grounding fault, the cabinet is fully enclosed, the grounding point is difficult to find, and the bus operation is complicated, which increased the difficulty and time of accident processing. In response to this problem, the article proposes finding methods, prevention and improvement measures for the single-phase grounding fault of the cabinet.