UR T35/T60变压器差动保护误动分析  

Analysis on mal-operation of UR T35/T60 transformer differential protection

作　　者：方愉冬[1] 杨涛 吴春娣 

机构地区：[1]浙江电力调度通信中心,浙江杭州310007 [2]浙江电力试验研究院,浙江杭州310004 [3]镇海发电厂,宁波镇海315208

出　　处：《电力系统保护与控制》2009年第14期118-121,共4页Power System Protection and Control

摘　　要：针对某电厂T35/T60变压器差动保护误动,对保护数据波形和整定值进行了分析。根据波形特征理论分析,排除了和应涌流引起差动保护误动的可能,指出系穿越性励磁涌流的非周期分量导致CT暂态饱和,从而引起采用"2-out-of-3"谐波制动方式的差动保护误动。最后针对误动事故,提出了T35/T60保护二次谐波制动方式选择和差动动作曲线整定上应采取的措施。The paper analyzes fault data and protection setting during a mal-operation of UR T35/T60 transformer differential protection relay. Based on theoretical analysis of waveform character, possibility of sympathetic inrush resulting in mal-operation is ruled out, and conclusion is drawn that mal-operation was caused by differential protection＇s ＂2-out-of-3＂ 2nd harmonic restraint mode and TA transient saturation due to through-by inrush current. The corresponding solution of real-operation is proposed on T35iT60 relay percent differential operating characteristic setting and 2nd harmonic restraint choice.

关 键 词：主变差动保护 励磁涌流 CT暂态饱和 误动 

分 类 号：TM772[电气工程—电力系统及自动化]