Time-Domain Homogenization of Litz-Wire Bundles in FE Calculations

This paper deals with a time-domain homogenization technique for Litz-wire bundles embedded in a finite element (FE) model. An elementary FE model is used to determine dimensionless frequency- and time-domain coefficients regarding the skin and proximity effects in Litz-wire bundles. Thanks to these coefficients, Litz-wire bundles become homogeneous conductors which are easy to integrate into a FE model of a complete device. The method is validated with the reference solution of the 2-D FE transformer model, which is computed by finely discretizing each conductor. The results agree well with the accurate reference solution.status: publishe