An Air-Gap Shape Optimization for Fringing Field Eddy Current Loss Reductions in Power Magnetics

This study reduced winding eddy current losses by optimizing the shapes of air gaps in inductors. Finite element method software was used for inductor simulations. A special script was made to implement an optimization algorithm to reach a minimum of an objective function. The objective function consisted of two weighted parts. The first part was the total losses of an inductor, and the second was the average flux density of a central leg's core around a gap. A relationship between these parts was used to determine how deeply the inductor could be saturated to minimize the total loss of the inductor. Simulation results and experimental data were noted, and the total loss and temperature reductions of the inductor were demonstrated.