开关死区(失灵)保护优化方案及测试应用

Breaker dead zone(failure) protection optimization scheme and test application

对于传统交流电网,目前的继电保护技术已日臻成熟,但是随着特高压交直流混联电网的形成,交流保护对电网特性变化的适应性亟待提升。本文针对开关失灵或CT死区故障时保护切除故障时间长、可能引发多回直流连续换相失败、导致系统发生的严重后果,介绍了两种开关死区(失灵)保护优化方案,将开关失灵或CT死区故障时切除时间缩短至200ms以内,防止引发电网稳定破坏事故,并搭建了测试系统,对优化后的开关死区(失灵)保护的性能指标进行了详细考核,对系统中发生异常运行工况时开关死区(失灵)保护的动作情况进行了验证测试,从而保证优化后的开关死区(失灵)保护在电力系统中运行的稳定性和可靠性。

The relay protection technology is becoming more and more mature for the traditional AC power grid,but with the formation of UHV AC and DC hybrid power network,the adaptability of AC protection to the characteristics of the power grid needs to be improved.In view of the breaker failure or the CT dead zone fault,the removal of the fault time is long,which may lead to the failure of the multiple DC continuous commutation,resulting in the serious consequences of the system.In this paper,two kinds of breaker dead zone(failure)protection optimization scheme is introduced,which shortens the excision time to less than 200ms when the breaker failure or the CT dead zone fault is broken down to prevent accidents caused by power grid stability damage.And it builds a test system.The performance index of the optimized breaker dead zone(failure)protection is examined in detail,and the action situation of the breaker dead zone(failure)protection in the abnormal operation condition is verified and tested,so as to guarantee the optimized breaker dead zone(failure)protection operation stability and reliability in power system.