“…spiral tightening, conductor tilting, radial/hoop buckling, shorted or open turns, loosened clamping structures, axial displacement, core movement, and collapse of the winding end supports [7,8]. Frequency response analysis (FRA) is known as the most reliable non-invasive diagnostic technique currently used to identify incipient winding deformation within power transformers [9,10]. Transformer components such as windings, core and insulation can be presented by equivalent electrical parameters comprising resistors, capacitors, and self / mutual inductances, whose values are altered due to any winding deformation leading to a change in the frequency response of the relevant equivalent circuit.…”