一起大型变压器低压侧升高座过热原因分析及处理

Reason Analysis and Solution to Overheating of Ascending Flanged Base at Low Voltage Side of Large Transformer

随着变压器容量的增大,变压器低压侧引线电流高达20~30 k A,大电流产生的漏磁场和涡流损耗导致变压器邻近的金属构件局部过热严重,影响变压器的正常稳定运行。某发电公司5号主变压器自投运以来低压侧升高座法兰盘长期超温,经过对发热原因的分析及试验,提出对法兰盘＂断磁通切槽＂的处理方案,在5C02检修中实行了技改,效果良好。

With increase of transformer capacity,leading current at low voltage side of the transformer reaches to 20-30 kA,leakage magnetic field and eddy current loss caused by large current may result in serious overheating of parts of metal components near to the transformer,which may affect normal and stable operation of the transformer.Flange plate of ascending flanged base at low voltage side of No.5 transformer of some generation company is overheating in a long period.By analyzing reasons for overheating and conducting testing,processing scheme of breaking flux grooving on the flange plate is proposed.Technology improvement in5C02 overhaul proves good effect of this scheme.