摘要
提出了一种适用于输电线路差动保护抗电流互感器(TA)饱和的新方法——电流极性比较法。该方法通过将输电线路二次电流和差流相应的瞬时值相乘再积分的方法来比较两电流的极性关系,以此区分内部故障和外部故障时的TA饱和。EMTP仿真计算表明,在输电线路外部故障且TA发生饱和时,电流极性比较法能够可靠地闭锁差动保护;而在内部故障尤其是外部转内部故障且发生TA饱和时,也能使保护快速开放。
A new countermeasure to current transformer （TA） saturation, namely, current polarity comparison method, for differential current protection of transmission line is proposed. It compares the polarity of the saturated current of TA and that of the differential current during internal faults and external faults with a special analysis method. EMTP simulation results show that the proposed method is able to successfully block the differential current protection during external faults even when TA saturates, and also quickly unblock it during internal faults, especially when an evolving fault occurs.
出处
《电力系统自动化》
EI
CSCD
北大核心
2009年第8期56-61,共6页
Automation of Electric Power Systems
关键词
输电线路差动保护
电流互感器饱和
电流极性比较法
转换性故障
line differential protection
current transformers saturation
current polarity comparison method
evolving fault
