A Novel DC Differential Method for High Frequency Core Loss Measurement

Precise measurement of core loss is crucial for the optimal design of magnetic components used in power converters. This paper proposes a novel magnetic core loss measurement method based on the direct current (dc) differential principle. Compared to the conventional dc core loss measurement method, which can only measure the total loss of a magnetic component, the proposed method can extract the core loss from the total loss. This enables the measurement of the inherent loss characteristics of magnetic materials, particularly those with low permeabilities, which usually cannot be measured with the conventional dc core loss measurement method. The proposed method is suitable for measuring core losses under various current waveforms up to MHz frequencies, including triangular, trapezoidal, and sinusoidal waveforms. An automatic testing platform is constructed to verify the proposed method, and the experimental results show high testing accuracy.