the batch defects of a 500 kV oil immersed current transformer were investigated. Through the diagnosis test and disassembly analysis
the main reasons for the defects of this type of current transformer are found to be the local wrinkled paper damage caused by the extrusion and friction between the body and the oil conservator. Under the high frequency overvoltage
the local wrinkled paper breaks down to produce acetylene. Finally
the corresponding suggestions and measures are put forward to provide reference for fault diagnosis and operation maintenance of the same type of current transformer.