Identification of Trouble of Transformer by Frequency Response Analysis

Frequency Response Analysis (FRA) is capable of detecting troubles of transformers, such as deformation of winding, displacement of winding and deformation of iron core, by detecting change of transfer function. However, interpretation of the change with reference to the trouble is not clear. In this paper, an identification method of the troubles are proposed based on investigation using a model transformer. Furthermore, proposed method is applied to a real transformer to identify trouble caused by short-circuit tests. The identification agrees with the result of dismantling investigation.