Non-Linear Eddy Current Loss and Thermal Analysis on Transformer Cover

Abstract

High current conductors of transformers cause to produce losses and thermal problems in theirtank cover. Finite Difference (FD) Method (FDM) magnetic analysis is used to find out an exactestimation of the magnetic field and the losses near the bushings in the transient solution,considering the non-linear magnetic permeability of the cover plate, because FDM is moreflexible to deal with the nonlinear constitutive law and easy-to-be implemented especially in thecase of simple geometry. Finite Element Method (FEM) thermal analysis is used to determinethe plate temperature based on magnetic FD analysis, taking account non-linear heat fluxboundary condition. A calibration procedure is used between the analyses to ensure the precisionof assumptions. The reliability of the technique, confirmed by experimental and FEM results.