Analysis of electromagnetic-mechanical stresses on the winding of a transformer under inrush currents conditions

The main objective of this paper is to assist in the investigation of electromagnetic forces, structural deformation, stresses, and Safety factor when energizing unloaded transformers. The methodology is based on modeling of a single-phase 50 MVA transformer subjected to inrush currents through finite element method (FEM). In this perspective, the conditions of inrush currents are used to estimate the magnetic field density dispersion in the transformer and to find the values of forces in axial and radial directions. These components are distributed along the energized windings for observing the loads in high- voltage windings. Thus, this article will contributes with the investigations of a structural Analysis on transformers when subjected to inrush current.

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