Abstract:

The change of the dissolved characteristic gas and its content in the transformer oil reflects the type and the severity of transformer internal fault. The threeratio method and the comprehensive analysis by fault model can basically determine the type and severity of the transformer fault. In the case of the C phase fault in the main transformer of #5 unit of a plant, the transformer is in need of overhaul. After the inspection with hanged hood, the discharge point is found inside the body. After treatment, the transformer is put into operation again and the measures to prevent the transformer fault are put forward. At present, the operation of the transformer is stable and oil chromatography is normal. The result shows that the diagnosis method is feasible and effective.

Key words:

fault model, transformer, comprehensive diagnosis, oil chromatography test, fault type, application