Relation between frequency dependence of eddy current loss and switching characteristics of square-loop core

It is shown that the reversal time versus excess applied field curve of a square-loop core is equivalent to the relationship between eddy current loss per cycle and frequency at Bm= Bs. The theoretical expressions for eddy current loss are introduced on the basis of the equations of domain wall motion and the relation of the number of domain walls to the applied field intensity which were obtained in connection with studies of the mechanism of magnetization reversal. Predicted values based on these expressions for 50% Ni-Fe tape core agree well with the observed losses at a frequency range in excess of 30 Hz.