P级TA饱和对数字式比率制动特性差动保护的影响  

Impaction of P-type CT saturation on digital ratio-restrained differential protection

作　　者：浦南桢[1] 翟学锋[1] 袁宇波[2] 陆于平[2] 

机构地区：[1]江苏省电力调度通信中心,江苏南京210024 [2]东南大学电气工程系,江苏南京210096

出　　处：《电力自动化设备》2003年第4期76-80,共5页Electric Power Automation Equipment

摘　　要：长期以来,比率制动曲线的比率制动部分历来都和电流互感器(TA)的抗饱和能力联系在一起。认为只要有了比率制动特性,差动保护就不会误动,但事实并非如此。长期统计表明有些原因不明的误动或多或少地和TA的暂态饱和有关。通过对非TPY级TA饱和的变压器区外故障动模数据分析,得出比率制动特性差动保护在P级TA暂态饱和情况下可能会误动的结论。同时,还详细阐述了选择合理的出口判据次数、数字滤波算法、数据窗的长度能提高差动保护抗TA暂态饱和能力的影响。For a long time ,the ratio-restrained characteristic is assumed to avoid CT saturation and the differential protection with ratio-restrained characteristic is considered able to function properly.The statistical data indicate that some unknown malfunctions of differentia l protection may be caused by CT saturation.Through the dynamic simulation analysis of non-TPY-type CT saturation at out-area fault,it is concluded that the differental protection with ratio-restrained characteristic may function improperly under P-type CT transient saturation.The influence of trip judgment times,digital filter algorithm and data-window width on the ability against CT saturation is discussed.

关 键 词：P级TA饱和 差动保护 电力系统 电网 继电保护 数字式比率制动特性 数字滤波 数据窗 

分 类 号：TM772[电气工程—电力系统及自动化]