Implementation and analysis Of large winding ratio transformers

The paper presents the work that has been carried out trying to improve the behavior and the performances of DC to DC step up converters with high conversion ratio. Especially, it is studied how the design and the realization of the magnetic HF transformer can be improved in order to increase the global efficiency of hard switch isolated DC to DC converters. It is shown that a split in conductors and then in magnetic core can be considered to improve the performances of the converter. Practical realization and implementation are used to validate the approaches considered in this paper. Thermal imaging helps to conclude on the work. Especially, it is shown that new technological approaches, for the passive but also the active devices, lead to better operations. The important results of the work are the presentation of a simple and very effective way to design and to build HF magnetic transformers with high transformation ratios thanks to an original winding technique. The new transformer structure is named SSWT. The second important result coming from this work is that interleaved structures added to technology and design may bring interesting results from electrical and thermal point of views.