华电技术 ›› 2012, Vol. 34 ›› Issue (9): 59-61.

• 技术交流 • 上一篇    下一篇

机组无保护动作跳机的原因分析及处理

巩芳杰   

  1. 广东省连州粤连电厂有限公司连州发电厂,广东连州513435
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2012-09-25 发布日期:2012-09-25

Analysis on reason of unit trip without protection device action and treatment measures

GONG Fangjie   

  1. Lianzhou Power Plant of Guangdong Lianzhou Yuelian Power Plant Company Limited, Lianzhou 513435, China
  • Received:1900-01-01 Revised:1900-01-01 Online:2012-09-25 Published:2012-09-25

摘要: 某电厂 #4机组连续2年几乎在同一时段无保护动作却发生机组跳闸。针对这一现象,从故障报告检查、回路检查、图纸设计和模拟故障试验等多方面进行了分析,最终确定机组跳闸原因为:事故照明回路存在缺陷,造成交流电窜入直流回路引起直流系统接地,导致机组出口开关跳闸。对事故照明回路进行了改进,消除定期切换时引起交流电源窜入直流系统的隐患。

关键词: 保护, 跳闸, 事故照明, 直流接地

Abstract: At almost the same time interval of the past two years, the unit No.4 of a power plant tripped while there was no protection device acted. Aiming at the phenomenon, the fault report was checked; the trip circuit was inspected; the design paper was analyzed; and the simulated fault experiment was carried out. The reason of unit trip was determined finally that there was defect in the emergency lighting circuit, which caused the AC power source to intrude into the DC loop during switchover operation in fixed period and made a grounding fault of DC system, and the grounding fault caused the unit outlet switch to trip. The emergency lighting circuit had been improved; and the hidden danger of the AC power source intruding into DC loop was eliminated.

Key words: protection, trip, emergency lighting, ground fault of DC system