Power Transformer Condition Assessment Using DGA and FRA

Power transformer condition assessment is a very complex task but also of high priority for power system reliability. Several diagnosis techniques have been published, specifically; insulation system condition assessment (paper and oil) using Dissolve Gas Analysis (DGA), and to assess winding and core condition, using Frequency Response Analysis (FRA). Results of these different techniques represent complementary or corroborative information of the final transformer condition. Therefore, unification of both techniques information helps to assess accurately transformer condition, which is very important in transformers management field and its failure risk estimation. In this paper, a novel method for DGA and FRA results unification is proposed, which is based on fuzzy sets application for failures detection and interpretation.