Analytical Time-Domain Eddy Current Loss Model for Simple 2-D Conductor Geometries and Arbitrary Exciting Waveforms

This article addresses the limitations of conventional frequency domain eddy current models for loss modeling under non-sinusoidal excitation and especially under a priori unknown and arbitrary exciting waveforms. A novel approach is presented, deriving a time domain eddy current loss model that provides a general solution for arbitrary exciting waveforms and closed-form analytical solutions for certain simple conductor geometries (e.g., round and rectangular). The model separates the spatial and temporal dependencies of the eddy currents, enabling the analysis of transient phenomena and visualisation of dynamic current redistribution. An efficient cumulative integration algorithm is presented for the computation of the time dependency. This makes the method particularly well suited for power electronics, where it can be applied to compute time domain phenomena in the conductors of inductor or transformer windings, either for analysing specific effects or in circuit simulations. Here, the cumulative step-wise algorithm enables very high computational efficiency. The proposed methodology offers a powerful tool for understanding and predicting eddy current behavior with potential extensions to core loss modeling.