220kV主变压器油中氢气含量异常分析与处理

Analysis and Treatment of Abnormal Hydrogen Content in 220 kV Main Transformer Oil

针对内蒙古某光伏电站的1起220 kV主变压器油中氢气含量超标故障,结合故障现象、测试数据,通过油色谱三比值法确定故障类型为局部放电。经过测试分析及原因排查,确定故障原因为主变压器内部受潮引起氢气析出。将主变压器停运,进行72 h真空滤油脱气及真空干燥,静置48 h重新投入运行,氢气体积分数稳定在23×10-6左右,异常情况得到解决。

In view of an abnormal hydrogen content event in 220 kV main transformer oil of a photovoltaic power station in Inner Mongolia,the causes are analyzed in depth combined with the event phenomenon,test records and the principle of oil chromatography three-ratio method.Through test analysis and cause checking,it is determined that the failure reason is hydrogen precipitation caused by moisture in the main transformer.Make the main transformer shut down to carry out the vacuum filter oil degassing and vacuum drying for 72 hours.The unit returns to service after 48 hours′standing.And the hydrogen volume fraction is stabilized at 23×10-6.The abnormal problem is solved.