考虑保护隐藏故障的系统N-k故障分析

Power System N-k Contingency Analysis in Consideration of Protection Hidden Failure

存在隐藏故障的继电保护会在系统发生N-1故障时,导致保护误动,对连锁故障扩大起着推波助澜的作用。从保护隐藏故障的动作机制出发,计及不同原理的保护装置和线路故障位置,对保护的隐藏故障模式进行分析,确定保护的风险区段,提出一种基于保护隐藏故障模式分析的N-k故障分析方法,将保护的隐藏故障反映到预想事故的选择和故障组合上。算例表明,采用该方法可定量评估电网中继电保护隐藏故障对系统可靠性的影响,发现系统的薄弱环节。

Hidden failure of protection leads to protection misoperation when N-1 contingency occurs in power system, which contributes to the expansion of cascading failure. Based on investigation of hidden failure mechanism, protection hidden failure modes were analyzed and vulnerability zone of protections were identified by consideration of different protective device and different fault location of the first contingency. N-k contingency analysis method based on protection hidden failure modes analysis was proposed, which linked protection hidden failures with contingency screening and false tripping line set identification. A case study shows the effectiveness of the proposed method by assessing effects of relay hidden failures on system reliability.