Buckling Strength Analysis of Large Power Transformer Windings Subjected to Electromagnetic Force Under Short Circuit

Abstract

The inner winding of a power transformer is subjected to radial electromagnetic forces under short circuit conditions. When these forces exceed a certain limit, transformer windings buckle. This paper deals with the buckling strength analysis of transformer windings, including the evaluation of the bending stiffness of a winding disk (coil) of multiple turn laminated construction, the effect of supporting spacers on the deformation of a winding and the plastic deformation of a winding caused by circumferential stress.