电流互感器饱和导致主变差动保护误动的分析  

Analysis of Undesired Activation of Main Transformer Differential Protection Induced by Saturation of Current Transformer

作　　者：伏箭文 王臣玺 FU Jianwen;WANG Chenxi(Yunnan Electric Power Technology Co.,Ltd.,Kunming 650217,China)

机构地区：[1]云南电力技术有限责任公司,云南昆明650217

出　　处：《电工技术》2024年第2期167-169,172,共4页Electric Engineering

摘　　要：主变差动主要反映变压器的相间短路故障、绕组匝间短路故障等变压器内部故障,并能快速动作切除故障电流,但如果其各侧CT中任一侧出现严重饱和,就将在主变区外故障时误动作。针对一起CT饱和导致的主变差动误动事件,通过试验、故障波形及CT回路的核查及分析,明确误动原因,提出解决方法,并在此基础上提出针对性建议,以防止类似事件的发生。The main transformer differential protection mainly reflects internal faults such as inter-phase short-circuit faults and winding inter-turn short-circuit faults,and can be quickly activated to remove fault current.However,if there encounters serious saturation by any side of current transformer,external faults will cause undesired activation of main transformer differential protection.This paper reports an event of CT-saturation-induced undesired activation of differential protection in an actual main transformer.It describes the processes of checking and analysis carried out through testing,fault waveform and CT loop,identifies the causes of undesired activation,and proposes solutions and countermeasures.

关 键 词：主变差动 区外故障 CT饱和 

分 类 号：TM452[电气工程—电器]