Simulation and Analysis of Dynamic Characteristics of Transformer Winding in Short-Circuit Fault by Finite Element Method

It is of great significance for the stability of power system to research the electromagnetic and mechanical dynamic characteristics of transformer in short-circuit fault by numerical simulation. A 110kV/25000kVA power transformer model is established by the finite element method. In which Ogden model is adopted to conduct simulation analysis on winding spacer for considering its nonlinear mechanical characteristics. Some simulation results are obtained on the basis of modeling. Firstly, the magnitude and distribution of the axial and radial electromagnetic force of windings in short-circuit fault are calculated. Secondly, the dynamic change rule of displacement and stress of high voltage and low voltage windings in short- circuit fault is obtained. Thirdly, the distribution of maximum displacement and maximum stress on each coil disk are calculated. In addition, the difference of mechanical characteristics between HV winding and LV winding is analyzed. The above results can provide reference for transformer design.