外部故障切除后变压器差动保护误动分析  

Analysis of maloperation of transformer differential protection after external fault clearance

作　　者：孙世勇[1] 

机构地区：[1]东北电力大学电气工程学院,吉林吉林132012

出　　处：《黑龙江电力》2011年第1期37-39,共3页Heilongjiang Electric Power

摘　　要：针对变压器差动保护在外部故障切除后误动和差流谐波问题,阐述了变压器外部故障切除的电磁全过程,分析了恢复性涌流和CT饱和对差动保护的影响,进行了差流谐波仿真分析,发现误动期间三次谐波含量比二次谐波高的现象。谐波分析和仿真结果表明,恢复性涌流二谐波含量较高,不是误动的根本原因,CT饱和是误动的关键因素。On the basis of maloperation and differential current harmonic of transformer differential protection after external fault clearance,this paper introduces electromagnetic process of external fault clearance,analyzes the influence of recovery inrush and CT saturation on differential protection,conducts simulation analysis of differential current harmonic during which it is discovered that the content of third harmonic is higher than that of secondary harmonic during maloperation.The result of harmonic analysis and simulation shows that the root cause of maloperation is not the relatively high content of recovery inrush but CT saturation.

关 键 词：恢复性涌流 CT饱和 谐波分析 

分 类 号：TM772[电气工程—电力系统及自动化]