Survey and Comparison of 1D/2D analytical Models of HF Losses in Litz Wire

Litz wire (LW) is essential for reducing HF winding losses in medium frequency transformers and inductors. In order to predict the losses and optimise the parameters of LW, several analytical loss models have been presented. However, a detailed comparison of the models and the accuracy is missing. Therefore, this paper presents a comprehensive comparison of four loss models with respect to general mathematical approach, computational effort, as well as the impact of different parameters on the accuracy of the different models. Guidelines and insights for choosing the most suitable model are also provided.