某变电站变压器直连故障原因分析

针对某变电站2号变66 k V侧C相油气套管部分严重烧蚀的问题,对烧蚀故障部位进行现场检查,确定了故障最初发生位置.通过对该故障间隔样品进行解体检查、关键零部件尺寸检测、不同接触情况下的接触电阻测量验证、分解物化验等试验,得出C相直连筒体内部导体连接部位接触不良发热,长期积累造成导体熔化,金属熔化物朝筒体内壁溅射造成接地故障.

Analysis of the Causes of Transformer Direct Connection Fault in a Variable Power Station

In view of substation for the serious ablative problem of C phase with Change 2 at 66 kV side,through the field inspection in the ablative fault site,the fault initial location is determined. Through the breakdown test,the key parts size test,contact resistance measurement under different contact conditions,decomposition test and so on,it is concluded that C phase direct connection to the inner conductor of the tube is in poor contact with the bad heat,the conductor melted by long-term accumulation. At last the ground failure is caused by the sputtering of metal melt material on the inner wall of the cylinder.