A Time-Domain Homogenization Technique for Laminated Iron Cores in 3-D Finite-Element Models

Abstract

The authors present a novel time-domain homogenization technique for laminated iron cores in three-dimensional (3-D) FE models of electromagnetic devices when using the magnetic vector potential formulation. The method is based on a polynomial orthogonal decomposition of the variation of the induction throughout the thickness of the laminations. The nonconstant components, due to skin effect, produce additional degrees of freedom and equations for the homogenized core. Insulating layers of finite width between the laminations (fill factor 1) are taken into account as well. A linear 3-D axisymmetric test case is considered. The results agree well with those obtained with the reference model, in which all laminations are finely discretized and the eddy currents are directly modeled.

Equivalent Permeability of Step-Lap Joints of Transformer Cores: Computational and Experimental Considerations

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“…In recent years, there have been several such attempts described in literature, most employing an analytical 1-D solution along the thickness of the sheet. Multidimensional orthogonal decomposition of the flux distribution has been used [5] both for a linear [6] and a nonlinear model [7]. The normal and tangential fluxes (referred to as "perpendicular" and "parallel" in the references) have been considered with appropriate modifications to the tensor of reluctances and conductances; a diagonal tensor has been used.…”

Algebraically constrained extended edge element method (eXFEM-AC) for resolution of multi-material cells

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Equivalent circuit modeling of dynamic hysteretic property of silicon steel under pulse width modulation excitation

“…Several homogenization methods [1][2][3] have been proposed for the efficient analysis of laminated iron cores while avoiding finite-element division along the stacking directions of the steel sheets. However, accurate evaluation of the eddycurrent field in a steel sheet with nonlinear magnetic properties is not easy without the use of sub-analysis methods, 1,3 including integral computation along the stacking direction.…”

“…However, accurate evaluation of the eddycurrent field in a steel sheet with nonlinear magnetic properties is not easy without the use of sub-analysis methods, 1,3 including integral computation along the stacking direction.…”