一起绝缘油老化导致变压器绝缘电阻降低案例分析OA

During the routine test in the factory,the insulation resistances of high voltage winding to ground,medium voltage winding to ground and low voltage winding to ground of a 500kV transformer are tested,and the results deviate from those of transformers in the same batch and type,which did not meet the requirements of the national standard. In this paper,starting from the transformer production process,the factors that may lead to the reduction of insulation resistance of the transformer are investigated and verified. Ultimately,the insulating oil aging is determined to be the main factor. According to this result,the insulation oil is replaced and the fault is successfully eliminated.