Example study of the dissipation factor change according to the oil filtering in large oil-filled transformer

유입변압기 오일필터링에 따른 유전정접 변화사례 고찰

This paper is purpose to understand the dissipation factor properties of the oil-filled large transformer according to the oil filtering. In order to know the insulation characteristic change by insulating oil filtering, we carried out the insulation diagnostic test for the same transformer before oil filtering and after. The insulation diagnosis tests are consist of the megger, the polarization index, the AC current test, the dissipation factor test and the partial discharge test, Especially we took notice of dissipation factor change, we analyzed and made a comparison of the two cases test result.