一起环氧树脂浇注电流互感器故障情况及处理分析  

Analysis and Handling of a Fault Case of Epoxy-casted Current Transformer

作　　者：柏树青 BAI Shuqing(Guangdong Power Grid Company Shaoguan Power Supply Bureau,Shaoguan 512000,China)

机构地区：[1]广东电网公司韶关供电局,广东韶关512000

出　　处：《电工技术》2024年第19期151-155,共5页Electric Engineering

摘　　要：通过对某站一起环氧树脂浇注电流互感器内部故障引起的设备故障进行分析,得出事故原因为电流互感器制造工艺控制不良及密封结构不良。故障发展过程为:35 kV回河线A相发生线路接地故障,BC相升高至线电压,在线电压作用下,302开关CT C相发生接地短路,导致内部高温高热气体混合碳化后粉尘从CT内部喷出,引发302开关BC相接地短路故障。因故障CT靠近主变侧,CT接地故障无法切除,CT故障进一步扩大,最终引起主变差动保护动作跳闸。据此对该型号(LQZF8-35W)电流互感器在制造工艺、交接验收、试验、技术规范书方面提出改进建议,以提高电流互感器运行的安全可靠性。Based on the analysis of the equipment failure caused by an internal fault of an epoxy-casted current transformer in a substation,the causes of the accident were found to be poor control of the current transformer manufacturing process and poor sealing structure.The development process of the fault is as follows:A phase of 35 kV return line encounters grounding fault,BC phase rises to line voltage,under the action of on-line voltage,302 switch CT C phase occurs grounding short circuit,the short-circuit causes the high-temperature and high-heat gas mixed with carbonized dust to spurt out from the inside of the CT,causing the 302 switch BC phase-to-ground short-circuit fault.Because the fault CT is close to the main transformer side,the CT grounding fault can not be removed,and the CT fault expands further,which finally causes the main transformer differential protection trip.Based on this,some suggestions are given for LQZF8-35W current transformers from the perspectives of manufacturing process,acceptance,test and technical specification,so as to improve equipment safety and reliability.

关 键 词：电流互感器 环氧树脂 浇注 

分 类 号：TM452[电气工程—电器]