Measurement and Modeling ofB–HLoops and Losses of High Silicon Nonoriented Steels

Two time-stepping methods based on the concept of magnetic viscosity have been compared from the viewpoint of their ability to reproduce the dynamic B-H loops and losses in nonoriented electrical steels with high silicon content studied experimentally. The methods are suitable for describing arbitrary magnetization regimes such as waveforms associated with pulsewidth modulation (PWM) voltage excitation. The model differential equations can be conveniently combined with equations of an external electric circuit. The accuracy of the proposed dynamic models is shown using two nonoriented electrical steels as examples. Fitting of the magnetic viscosity parameters for one sinusoidal flux regime enables dynamic hysteresis loops and losses to be predicted with high accuracy over a wide range of frequencies and amplitudes of sinusoidal or nonsinusoidal flux densities