Design and Comparative Analysis of Litz and Copper Foil Transformers for High Frequency Applications

This paper presents the comparative analysis of Copper Foil and Litz wound transformers for high frequency applications. The skin and proximity effects due to eddy currents are analyzed for both windings. The design and selection of foil and Litz windings for a high frequency transformer is discussed, and the designed transformers are compared on the basis of their AC resistance factor and leakage inductance. A method to reduce the AC resistance factor and leakage inductance for the two winding techniques is also proposed. The preference of Foil winding design for a high frequency transformer is validated by means of experimental results.