兴安直流“5.5”双极相继闭锁事件及保护动作行为分析

2008年5月5日兴安直流系统发生双极相继闭锁事件,通过对现场设备的检查、雷电定位系统信息、相关录波和继电保护动作情况的分析,查明了故障原因是极I直流线路多次遭受雷击后因过电压导致闭锁,与其同杆架设的接地极线路因感应电导致电流不平衡,并随着极I状态的改变而改变保护动作策略,最终导致双极相继闭锁。对事件暴露的问题提出了合理的改进措施。

Analysis of "5.5" Xing'an DC System Two Poles Locking Successively and Actions of Protection Mechanisms

In May 5,2008,an failure of double poles locking successively occurred in Xingan DC system.By examining on-site equipment and analyzing information from lightning positioning system,corresponding wave recorder,and actions of relay protection,it is clear that the cause of the failure is that pole I DC line was locked due to overvoltage after multiple lightning strikes,and faradism with the other ground line on the same pole causes current imbalance.The protection strategy is changed as condition of pole I va...