摘要
为了解决同塔双回线一回断线时健全线零序方向纵联保护误动的问题,提出了基于断线识别的零序纵联保护防误动策略。首先分析了同塔双回线一回断线期间健全线路零序纵联保护的误动机理,进一步提出了同塔双回线断线识别判据,利用健全线路故障前负荷电流和故障后零序电流的幅值及相位特征,区分邻线断线故障和本线接地故障。基于此,构造了零序纵联保护防误动逻辑,当邻线发生断线故障后,会自动闭锁本线两端零序电压补偿策略,从而能够有效防止零序纵联保护误动。最后通过数字仿真验证了所提出方法的有效性和可行性。
To solve the maloperation problem of zero-sequence pilot protection on the healthy line of parallel circuits on the same tower in the case of a broken line on the other circuit,a maloperation prevention strategy for zero-sequence pilot protection is proposed based on broken-line identification.First,the maloperation mechanism of zero-sequence pilot protection on the healthy line is analyzed when a broken-line fault occurs on the other circuit.Then,the broken-line identification criterion for parallel circuits on the same tower is proposed,which uses the amplitude and phase characteristics of load current before fault and zero-sequence current after fault on the healthy line to distinguish the broken-line fault on the adjacent line from the earth fault on the protected line.On this basis,the maloperation prevention logic of zero-sequence pilot protection is constructed:if a broken-line fault occurs on the adjacent line,the zero-sequence voltage compensation strategy will be closed at the two ends of this protected line,preventing the maloperation of zero-sequence pilot protection effectively.Finally,digital simulations verify the effectiveness and feasibility of the proposed method.
作者
姜宪国
周泽昕
杜丁香
李仲青
JIANG Xianguo;ZHOU Zexin;DU Dingxiang;LI Zhongqing(State Key Laboratory of Power Grid Safety and Energy Conservation,China Electric Power Research Institute,Beijing 100192,China)
出处
《电力系统及其自动化学报》
CSCD
北大核心
2018年第11期32-38,共7页
Proceedings of the CSU-EPSA
基金
国家重点研发计划资助项目(2016YFB0900604)
国家电网公司科技资助项目(JB71-15-036)
关键词
同塔双回线
零序纵联保护
断线识别
零序电压补偿
parallel circuits on the same tower
zero-sequence pilot protection
broken-line identification
zero-se-quence voltage compensation
