Comparisons of high frequency magnetic core losses under two different driving conditions: A sinusoidal voltage and a square-wave voltage

It is observed that for the same peak flux density and the same operating frequency, the core loss induced by a square-wave voltage drive is less than the loss induced by a sinusoidal voltage drive, which is contrary to what one would normally anticipate. To the best of the author's knowledge, there Is no theory that predicts the loss difference observed.