Semi-Lumped Model for U- and E-Cores for Calculating the Frequency-Dependent Complex Permeance

Ferrite material has non-negligible permeability, permittivity, and conductivity, so that the magnetic behaviour of ferrite cores is frequency dependent. This article presents a method to predict the complex permeance of ferrite E- and U-cores including electromagnetic resonance. The cores are decomposed into elementary segments, for which the Maxwell equations are solved analytically to obtain a network of frequency-dependent permeances or reluctances.