Modeling Magnetic Power Losses in Electrical Steel Sheets in Respect of Arbitrary Alternating Induction Waveforms: Theoretical Considerations and Model Synthesis

We describe a numerical approach to determine the magnetic power losses caused by alternating magnetizations in thin electrical steel sheets. This paper deals with the evaluation of different loss models which are suitable for postprocessing strategies and distinguishes between analytical equations and numerical procedures. We include improved approximations of the hysteretic and excess loss behavior of ferromagnetic materials into the 1-D partial differential equation that governs the field distribution in thin sheets. The focus of application of the developed loss model lies on nonsinusoidal magnetizations covering high induction values to at least 1.9 T in case of nonoriented steels and a wide frequency range from 25 Hz to at least 2 kHz. We modified existing descriptions of the field contributions due to hysteresis and excess loss to circumvent the limitation to low inductions of the original formulations. Our approach is experimentally verified by testing a variety of nonsinusoidal waveforms which cover considerable minor hysteresis loops and a wide span of induction and frequency values.