Accurate Magnetic Core Losses Measurement Under Arbitrary Excitation Waveforms

Precise core loss measurements are essential for magnetic design and the development of efficient and high-power density converters. This letter introduces a novel approach, leveraging the fast Fourier transform (FFT), to couple with the already demonstrated partial cancellation concept adopted for transformer core loss measurements. The proposed method perfectly eliminates the reactive voltage of the transformer under test contrary to the widely used two-winding method, yielding accurate core loss measurements regardless of the type of excitation waveform and design of the reference air core transformer. Experimental validation is performed by testing material N97 under both sinusoidal and rectangular excitations in the frequency range from 100 kHz to 500 kHz.