一起主变差动保护动作事故分析和仿真研究  

Analysis and Simulation Research on a Differential Protection Action Accident of Main Transformer

作　　者：应宇鹏 马秀林 林鹏 常俊晓 YING Yupeng;MA Xiulin;LIN Peng;CHANG Junxiao(Taizhou Power Supply Company,State Grid Zhejiang Electric Power Co.,Ltd.,Taizhou Zhejiang 318000,China)

机构地区：[1]国网浙江省电力有限公司台州供电公司,浙江台州318000

出　　处：《湖北电力》2024年第5期106-113,共8页Hubei Electric Power

基　　金：国网浙江省电力有限公司科技项目(项目编号:5211TZ230011)。

摘　　要：对一起主变差动保护动作事故进行分析和仿真研究。通过保护动作分析和录波数据分析,得到主变差动保护动作原因为主变低压侧B相避雷器发生损坏接地后,差动保护区外又出现了C相接地故障,不同点的异名相接地导致主变B相差流增大,达到保护整定值动作。同时,基于Simulink软件搭建电路模型对该类故障进行仿真研究,仿真结果与事故情况相符。本研究可为类似故障的分析和处理提供参考。This paper makes analyses and simulation studies on an accident of differential protection action of main transformer.The analysis of protection action and wave recording data finds that the reason for the differential protection action of the main transformer as follows:After the B-phase lightning arrester on the low-voltage side of the main transformer is damaged and grounded,the C-phase ground fault occurs outside the differential protection area,and the grounding of different phases at different points leads to the increase of the differential current of B-phase,which reaches the protection setting value.At the same time,a circuit model is built based on Simulink software to simulate and study this kind of fault,and the simulation results are consistent with the accident situation.This study can provide reference for the analysis and treatment of similar faults.

关 键 词：主变 差动保护 中性点不接地系统 异名相接地 变压器 电流互感器 

分 类 号：TM77[电气工程—电力系统及自动化]