On the analysis of the dynamic energy losses in NGO electrical steels under non-sinusoidal polarization waveforms

This article presents a discussion on the main approaches for the characterization and modeling of the dynamic energy losses for a non-grain-oriented (NGO) electrical steel excited with either sinusoidal or non-sinusoidal magnetic inductions. The experimental analysis is carried out via an Epstein frame, where an efficient feedback algorithm is implemented to control the magnetic-induction waveform. Different approaches are tested to reproduce the dynamic energy losses, including analytic equations and a dynamic hysteresis model, based on the solution of the diffusion equation via a finite-difference time-domain (FDTD) scheme, where the hysteretic constitutive law is modeled according to the Preisach model. Discussion on the accuracy of different approaches in the reproduction of the energy loss components is presented.