Accurate modeling of voltage and current waveforms of nonlinear inductors with finite elements

In this paper, we present a theoretical-experimental comparison of the voltage and current waveforms of an inductor which is included in a buck DC-DC converter at switching frequencies of 40 kHz and 100 kHz. Theoretical waveforms are obtained by combining separate magnetic and electrical modeling procedures. The magnetic modeling is done by Finite Element Analysis (FEA) while the electrical modeling is carried out with a commercial circuit simulator. We study the application of the procedure to an inductor with a ferrite core. It is applied specifically to an RM-shaped core used in power electronics. The comparison between measurements and numerical data obtained from simulations validates the procedure.