Detection of deformation and displacement of transformer winding by frequency response analysis

Frequency response analysis (FRA) is a diagnosis method to detect troubles of a transformer, which are deformation and displacement of winging and so, by detecting change of a transfer function compared with that measured when the transformer is normal. However, identification of the troubles detected by FRA is not clear. In this paper, firstly, identification method of the troubles is investigated using a model transformer. Secondly, the proposed identification method is applied to identify a trouble of a real transformer caused by short-circuit tests.