Diagnostics of Transformer Windings Deformation Based on Transfer Function

The deformation of transformer windings after a short circuit was analyzed by studying the criterion for the transfer function. First, the lumped parameter method was used to establish the equivalent circuit of transformer winding, the losses, and mutual inductance was added in it. Second, a single-layer continuous transformer winding was used as an example to calculate the changes in equivalent circuit parameters due to the changes of the structure and geometry size of the transformer winding, when the transformer windings occurred different forms and degrees deformation. Finally, the common axial and radial deformations of transformer winding was studied to calculate the transfer function of the deformed winding, with the degree of winding deformation judged by the mean square root of the spectrum difference, a diagnostic criterion was given to judge the deformation degree.