Design of a 28 V-to-300 V/12 kW Multicell Interleaved Flyback Converter Using Intercell Transformers

Abstract
A low-input voltage high-power realization is presented with the aim to demonstrate the feasibility and the interest of topologies using intercell transformer. They constitute a promising option to interleave converter stages, and therefore, can answer to the specifications considered in this paper. These specifications require a galvanic insulation and the chosen topology is the Intercell Transformer (ICT) flyback converter, previously proposed by the authors. In a first part, the operating principle of the ICT flyback converter is recalled. The second part presents briefly the main features of the intercell transformer design, more precisely described in a previous paper. This part includes a discussion about the choice of the cell number. The last part presents the design and the implementation of the complete flyback converter using eight cells. A preliminary work concerns the choice, the design, and the test of each cell elements, mainly the transformer and the primary switching stage. In the end, the experimental results are presented and discussed. They demonstrate the potential of this original topology that needs only one level of magnetic components. Considering the suitability of the converter interleaving for the high-power-low-voltage applications, the ICT flyback converter constitutes a good candidate in that field.