Loss simulation of amorphous transformer core by frequency domain FEM coupled with dynamic hysteresis model considering skin effect

Purpose The purpose of this study is to propose a frequency-domain finite element method (FEM) coupled with a dynamic hysteresis model to improve the simulation accuracy of magnetic fields and iron losses of amorphous transformer cores. Design/methodology/approach The loss separation theory, the inverse Preisach model and the eddy current equations accounting for the skin effect are applied to generate the dynamic hysteresis model. The fixed-point technique is implemented to improve the nonlinear convergence. A filter method with relaxed reluctivity is proposed to avoid the precision loss of the Fourier transform when integrating hysteresis loops into the frequency-domain FEM. Findings The simulation results are validated by comparing them to the measurement results of a voltage-driven amorphous transformer under the excitation with a broadband frequency range. Comparison results of the proposed method and the conventional FEM using magnetization curves are discussed in the simulation of loss and exciting currents. Originality/value A nonlinear frequency-domain FEM coupled with a dynamic hysteresis model considering the skin effect is proposed and applied on the simulation of amorphous core under a broadband frequency range. The issues and possible solutions when integrating hysteresis model into frequency-domain FEM are discussed in detail.