A fast method for the calculation of foil winding losses

This paper introduces a new two-dimensional (2D) modeling approach for the fast calculation of inductor and transformer foil winding losses. The proposed modeling procedure is derived from the Partial Element Equivalent Circuit (PEEC) method, which is originally a full three-dimensional (3D) electromagnetic solution technique. With the presented modifications, the PEEC method can take into account the influence of an air gap fringing field and core material boundaries as well as skin- and proximity effect. A comparison to 2D Finite Element Method (FEM) simulations shows that the developed PEEC-based approach exhibits similar accuracy but shorter calculation times than the classical FEM modeling techniques typically employed for the calculation of non-uniform current distribution within foil windings. The new modeling approach is experimentally verified by calorimetric loss measurements of a gapped foil winding E-core inductor. Due to the fast calculation speed of the new approach, optimizations of inductive components with foil windings over a wide design space are finally possible.