A Simplified Dc-Bias Injection Method with Mirror Transformer for Magnetic Material Characterization

This paper presents a simplified dc-bias injection circuit using a mirror transformer as a part of an automated data acquisition system for the characterization of soft magnetic materials for power electronics applications. Modified from the existing three-winding method for minimizing the reflected voltage on the dc-bias injection circuitry, the proposed two-winding method offers improved accuracy with reduced equipment complexity and capability. It enables rapid and fully automated material characterization across wide frequency, flux density, excitation waveform, temperature, and dc-bias ranges.