Research on Radial Stability of Large Transformers Windings Under Multiple Short-Circuit Conditions

The radial instability of conductors of windings in large transformers becomes serious under multiple short-circuit conditions. The build-up effect of multiple short-circuit conditions cannot be simulated by the traditional analytical calculation. This paper presents a nonlinear buckling analysis method to compute and analyze the deformation of windings for a short-circuit test model transformer. The initial defect, which is computed based on a multispan elastic-support model, is used as the initial condition of magnetic-mechanical coupling analysis using the finite-element method. To validate the feasibility and applicability of the proposed method, the numerical results in a case study obtained from the proposed method are compared with those of experimental ones.