Loss decomposition under two-dimensional flux loci in nonoriented steel sheets

Energy losses have been investigated as a function of magnetizing frequency (DC - 200 Hz) and peak polarization value (0.25 T- 1.7 T) in non-oriented Fe-Si laminations under controlled alternating, elliptical, and circular flux loci. It is shown that, exploiting the concept of loss decomposition and the ensuing interpretative framework provided by the statistical theory of losses, a phenomenological approach to the energy loss prediction under two-dimensional fluxes can be formulated. The treatment conspicuously relies on the analysis of the excess loss component and its frequency dependence, which is observed to follow to a good approximation a law of the type W exc ∝ f 1/2, whatever the flux loci. It is concluded that the behavior of the energy loss under elliptical flux can be predicted to a good approximation as a function of frequency, peak polarization, and degree of ellipticity by preemptive experimental determination of the energy loss under alternating field and circular polarization at selected frequencies.