Effective electromagnetic field analysis using finite element method for high frequency transformers with litz-wire

This work presents an effective electromagnetic field analysis using the finite element method for high frequency transformers with litz-wire. The Joule loss for the litz-wire can be accurately determined by considering both the skin effect and proximity effect. Efficient transformers can be designed by investigating both the impedance characteristics and the heat generation. We show the analysis results of the Joule loss, the iron loss and the temperature in the transformer. The validity of the results has been confirmed by experiments.