LAUSR

Core losses of dc-biased Fe-Si-Al and Fe-Ni cores were measured. Changes of shapes and amplitude of ac loops, and permeability were attributed from the incremental permeability derived from dc loops. Core loss decreased with increasing dc field and then increased abruptly regardless of frequency in the cores with high permeability. It seemed that the decrease of the core loss with increasing dc field was attributed from decrease of dc hysteresis loss. Increase of the loss was seemed to be attributed from increase of amplitude of ac field which was also due to decrease of incremental permeability.