Core Loss Model for Nonsinusoidal Excitations Based on Vector Magnetic Circuit Theory

With the development of switching devices towards high frequency, the prediction and calculation of magnetic material losses under high frequency have become increasingly important. Moreover, in modern power electronics, the real excitations across magnetic materials are usually nonsinusoidal. Thus, an analytical magnetic core loss calculation model is proposed based on the vector magnetic circuit theory to calculate the magnetic core loss under non-sinusoidal waveform excitation at high frequencies in this article. By Fourier decomposition, the numerical mapping relationship between magductance and hysteretance under sinusoidal excitations is established. Based on the mechanism of hysteresis loss and eddy current loss, the losses under non-sinusoidal excitations can be directly calculated only based on the parameter values of magductance and hysteretance under sinusoidal excitation. The accuracy and effectiveness of the proposed method has been verified by comparing the predicted and measured data of three different magnetic cores 3E6, N30 and N87.