Core loss analysis of soft magnetic composite under non-sinusoidal excitation based on finite element models

Abstract

Due to the effect of higher harmonics on magnetic properties under actual complex operating conditions, the accurate calculation of core losses of soft magnetic composites (SMC) is complicated. First, this paper improves the existing SMC model by introducing a correction factor to correct the hysteresis loss coefficient so that the model can consider the local variation characteristics of the magnetic density waveform and then calculate the core loss under different harmonic excitation. Then, the influence of skin effect and inhomogeneous flux density within the ring sample model is analyzed. Finally, to validate the improved model, it is compared with other models in the reference based on experimental measurements, respectively. The results show that the core loss calculated by the improved model is closer to the experimental results under different harmonic excitations. In addition, the applicability of the improved SMC model under triangular and square wave excitations is also verified by the derivation of the equations.