基于电流极性比较的抗电流互感器饱和新方法  

A Novel Method for Current Transformer Saturation Countermeasure Based on Comparing Two Currents' Polarities

作　　者：陈丽艳[1] 何奔腾[1] 钱国明[2] 张永刚[2] 

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027 [2]国电南京自动化股份有限公司,江苏省南京市211100

出　　处：《电力系统自动化》2009年第8期56-61,共6页Automation of Electric Power Systems

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.

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 

分 类 号：TM773[电气工程—电力系统及自动化]