General Diagnosis Methods For Overheating Faults of Power Transformers

摘要

The incipient faults of power transformer mainly consist of overheating and discharge. In them, overheating faults occupy a large proportion, if not handled in tune, transformer will be damaged. However, the types of overheating faults are varied, and theiraccurate diagnosis is difficult. Practice proves DGA can determine whether there is an overheating fault. It is also proved that the electrical experiments represented by DC resistance and the infrared temperature measurement can determine the cause and position of the faults. Based on these and on the mechanism of all kinds of overheating faults, this paper systematically proposed the general diagnosis method to analyze the property, position, reason of the faults and the proposed method is based on DGA analysis coupled with relevant electrical experiments and infrared measurement. In this paper, the proposed method is applied to practical cases and the results show this method is realistic and effective for typical overheating fault diagnosis of small and medium sized transformers.