Advanced model of laminated magnetic cores for two-dimensional field analysis

A numerical model for the analysis of laminated ferromagnetic cores of electromechanical devices is presented. The model is based on the finite-element solution of the two-dimensional (2-D) electromagnetic field problem in the lamination plane; a dynamical relation between local magnetic flux density and magnetic field strength is obtained by solving for the one-dimensional (1-D) eddy-current field developed in the lamination depth. The hysteresis of the magnetic material is accounted for by the Preisach approach. The model is first validated by comparison with an alternative held formulation available for axis-symmetric structures; finally, an application to a more complex 2-D laminated core is presented and the numerical results are confirmed by comparison with measured waveforms of electrical and magnetic quantities.