启动给水泵时机组误跳闸的故障分析

Analysis of unit protection misoperation when starting feed water pump

针对启动1号给水泵时,1号发电机-变压器组差动保护有时会误动的情况,经过分析和计算,确认1号高压厂用变压器高压侧电流互感器C相二次出线IC441与ICN441接反,是造成差动保护误动的直接原因,经验证无误后,恢复了IC441与ICN441的正确接线,消除了主设备的主保护长期遗留下的事故隐患。

When start up No.1feed water pump ,the differential relay protection of No.1generator-trans-former set may happen misoperation.By analysis and calculation,it is confirmed that the secondary out puts I C441 and I CN441 on phase C of the current transformer at high voltage side of No.1high voltage transformer are reversedly connected.After in spection and verification,the mistake is corrected.