Identification of frequency effect on magnetic hysteresis and modelling with an internal variables model

In this paper, the first magnetisation response experimentally observed on 0.5 mm thick sheets made of a non-oriented silicon-iron alloy is given for different magnetic loading frequencies from 0.05 to 500 Hz. An internal variable magnetic hysteresis model is identified from the quasi-static response (from 0.05 to about 5 Hz.). This model is used for finite element analyses performed to predict the electro-magnetic response of the material at higher frequencies. The comparison between the results of these structural analyses and the experimental results proves that in this case the macroscopic eddy currents are sufficient to explain the total frequency effect on the magnetic hysteresis measurements.