Ladder Circuit Modeling of Dynamic Hysteretic Property Representing Excess Eddy-Current Loss

Bertotti’s model for excess eddy-current (EC) loss is combined with the dynamic hysteresis model represented by a Cauer circuit and the play model. The excess EC field of the Cauer circuit is represented by nonlinear resistors. A formulation of excess EC field based on nonlinear current conduction is developed for the finite-element EC analysis, which is applied to the physical Cauer circuit. The proposed models improve the ac iron-loss evaluation under sinusoidal excitation of frequencies up to 20 kHz and achieve an accurate <inline-formula> <tex-math notation="LaTeX">$B$ </tex-math></inline-formula>–<inline-formula> <tex-math notation="LaTeX">$H$ </tex-math></inline-formula> loop representation under pulse-width modulation excitations.