基于变压器负序电信号的匝间故障检测方法  

Turn to Turn Fault Detection Method Based on Negative Sequence Electric Signal of Transformer

作　　者：阎怀东 YAN Huaidong(State Grid Jiangsu Electric Power Co.,LTD.m Yancheng Power Supply Branch,Yancheng Jiangsu 224000,China)

机构地区：[1]国网江苏省电力有限公司盐城供电分公司,江苏盐城224000

出　　处：《电子器件》2020年第5期1035-1041,共7页Chinese Journal of Electron Devices

基　　金：盐城供电公司资金集中支付咨询项目(SGJSYC00CWJS1701090)。

摘　　要：变压器绕组匝间绝缘损坏造成线匝短接会引起匝间短路,从而导致绕组变形甚至烧毁,数字继电器能够计算变压器的一次侧和二次侧的负序电流以及二者之间的相位差,通过相位和幅值信息来检测变压器绕组匝间故障。但变压器二次绕组没有电流流过时,负序电流检测算法不足以准确检测匝间故障。为此本文提出了一种基于负序电流和负序电压的故障检测方法,设计了配套的信号继电器,并开发了一套信号检测算法来检测匝间故障,试验研究了过励磁、电流互感器饱和、零故障电阻、变压器励磁、外部故障等工况对检测精确度的影响;对比分析了不同工况对差分电流算法和本文算法的灵敏度的影响。结果表明本文设计的继电器在变压器励磁过程中也能保持较好灵敏度,从而准确检测匝间故障,提出的算法比差分电流算法更加灵敏,能够准确检测匝间故障。The turn to turn short circuit caused by the insulation damage of the transformer winding can cause the turn to turn short circuit,which leads to the winding deformation and even burnout.The digital relay can calculate the negative sequence current and the phase difference between the primary side and the secondary side of the transformer,and detect the turn to turn fault of the transformer winding through the phase and amplitude information.However,when there is no current flowing through the secondary winding of the transformer,the negative sequence current detection algorithm is not enough to accurately detect the turn to turn fault.In this paper,a signal relay based on negative sequence current and negative sequence voltage is designed,and a set of signal detection algorithm is proposed to detect turn to turn fault.The influence of over excitation,current transformer saturation,zero fault resistance,transformer excitation,external fault and other conditions on the detection accuracy is experimentally studied.The difference current algorithm under different conditions and the flexibility and sensitivity of the algorithm in this paper are compared and analyzed.The results show that the relay designed can also maintain a good sensitivity in the process of transformer excitation,so as to accurately detect the turn to turn fault.The proposed algorithm is more sensitive than the difference current algorithm,and can accurately detect the turn to turn fault.

关 键 词：变压器绕组 负序信号 故障检测 数字保护 

分 类 号：U226.5[交通运输工程—道路与铁道工程]