摘要
电压切换回路中刀闸辅助接点异常是使得线路或变压器保护不能采到母线电压而误动的主要原因。本文通过分析一起因刀闸常闭辅助接点粘连引起保护误动的事件,总结了现有电压切换回路存在问题,并提出了现有改进方案存在的隐患。本文提出了可避免保护失压的三种方案,并对其中可彻底消除隐患的微机化改造方案设计了具体的实现逻辑。
Protection＇s misoperation will be caused when line and transformer protection in normal operation cannot collect the bus voltage. It is one of the main reason that the abnormal auxiliary contact of disconnecting links in voltage switching circuit. This essay summarizes what causes the abnormality in voltage switching circuit by analyzing a case of line protection misoperation because the auxiliary contact is adhesive which is normally closed. For these causes, the hidden danger of improvement project now available has been raised. Then there are three improvement projects can effectively avoid the risk of protection＇s voltage-loss has been designed and put forward, one of which can eliminate the danger is microcomputer-based voltage switching circuit and its specific realization logics are designed.
出处
《电气技术》
2016年第1期90-93,共4页
Electrical Engineering
关键词
电压切换
二次异常并列
辅助接点
voltage switching
abnormal paralleling of secondary circuit
auxiliary contact
