Quantitative analysis and comparison of offline and online methods used to detect the core multi-point grounding fault

Multipoint grounding of transformer core is one of the common faults of transformer. In this paper, a transformer was detected by the electrical performance tests and gas chromatography experiment. Based on this failure, the finite element analysis was carried out to quantify the effects of various parameters on the fault. Finally, this paper summarized the basic theory of quantitative analysis and comparison of offline and online detection methods and proposed how to use different detection methods when detecting the core multipoint grounding fault.