Magnetic Core Losses under Square-wave Excitation and DC Bias in High Frequency Regime

Abstract

This paper aims to provide more insight into core losses at high frequency (MHz range) with superimposed DC bias. Inductive cancellation method is employed to reduce measurement sensitivity to phase errors. PC200 material was used for frequency range 1 - 3 MHz. Measurement results show higher $B$ field excitation results in ß parameter shift in Steinmetz parameter. At higher frequency, similar behaviour is found in α parameter. DC bias is found to bring significant loss increase. To address the parameter shift and increased losses, several new modifications are proposed. The ßeff and αeff improves the curve fitting accuracy. The Hinc and γ are proposed to account for DC bias impact. These modifications can help core losses prediction for engineers.