Simple models for dynamic hysteresis which add frequency-dependent losses to static models

The broadening of magnetic hysteresis with increasing frequency of excitation may be represented in an electrical equivalent circuit by placing a resistor in parallel with an inductor whose core is the magnetic material represented by a static hysteresis model. This broadening can be controlled as an arbitrary function of frequency by changing the resistance with frequency. This, in turn, may be accomplished by using a parallel set of linear resistors, each placed in series with a bandpass filter, in place of a single resistor. This technique is illustrated by a simulation of both fast pulse excitations and moderate frequency sinusoidal excitations for 3C81 ferrite material using an equivalent circuit containing just three resistive parallel branches along with the static hysteresis model of Jiles and Atherton.