Classical review of frequency response analysis of transformer

Frequency response analysis is very powerful method for identification of mechanical deformation in transformer winding. Input voltage gets supplied to one end of transformer winding and response is measured at another end of the winding in this method. The measured response is compared with reference set, and if deviation is found, a deformation is suspected. This paper reviews the basic electric parameter study, effect of electric parameter variation on different region of frequency response analysis, fault analysis and statistical techniques for identification mechanical deviation in transformer.