Predicting magnetic losses in HGO steel sheets under distorted induction waveform

We show that the magnetic losses of thin high-permeability grain-oriented Fe-Si sheets can be coherently assessed under sinusoidal and non-sinusoidal induction waveform by the analytical formulations provided by the Statistical Theory of Losses. Results are provided regarding the energy loss measured in 0,18 mm thick commercial sheets under sinusoidal induction and its change, for given peak polarization value J_p, with the distortion introduced by a third harmonic of defined amplitude J_p3 and phase j₃ relationships with respect to the fundamental component. It is shown that accurate prediction of the 50 Hz losses at J_p = 1.7 T for distortion generated by third harmonic peak polarization ratio J_p3/J_p1 = 0.1, 0.2, with j₃ ranging between 0° and 180° can be made by the sole knowledge of the sinusoidal losses.