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

Year 2019, Volume: 32 Issue: 2, 558 - 570, 01.06.2019

Mohammad Zia Zahedı İres Iskender

Abstract

High current conductors of transformers cause to produce losses and
thermal problems in their tank cover. Finite Difference (FD) Method (FDM)
magnetic analysis is used to find out an exact estimation 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 more
flexible to deal with the nonlinear constitutive law and easy-to-be implemented
especially in the case of simple geometry. Finite Element Method (FEM) thermal
analysis is used to determine the plate temperature based on magnetic FD
analysis, taking account non-linear heat flux boundary condition. A calibration
procedure is used between the analyses to ensure the precision of assumptions.
The reliability of the technique, confirmed by experimental and FEM results.

Keywords

Eddy current loss, Finite Difference method, Finite element simulation, Hot spot temperature, Transformer cover

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