Long-term high-temperature operation degrades the performance of insulating components

which exacerbates winding displacement under short-circuit forces and weakens short-circuit withstand capability.However

existing verification methods often fail to systematically account for the coupled influence of temperature.To address this gap

this paper first derives calculation methods for leakage magnetic fields

short-circuit currents

forces

and axial winding displacements under varying temperature conditions.Subsequently

the elastic modulus of insulating components(spacers and stays)and the magnetic characteristic curves of silicon steel sheets are experimentally measured at different temperatures.Based on these data

a two-dimensional finite element model of a 750 kV main transformer is established to simulate leakage magnetic fields

forces

and winding displacement at different temperatures.The results show that the elastic modulus of insulating components decreases significantly with increasing temperature.The magnetic induction of silicon steel sheets slightly decreases at high temperature.In addition

winding displacement increases markedly with temperature.This study summarizes the variation law of winding displacement with temperature under short-circuit current

providing a scientific basis for short-circuit withstand verification of long-term operating transformers and contributing to the improvement of existing verification frameworks.