Interleaved three-phase forward converter using integrated transformer

An interleaved three-phase forward converter using an integrated transformer is proposed in this paper. This type of converter has the attractive features of flexible voltage conversion ratio, high output current (due to the parallel connection of outputs), near-zero output-current ripple (due to the output-current-ripple cancellation), fast transient response (due to the small effective output-filtering inductance), and is particularly suitable for high-output-current and low-output-voltage applications such as telecommunication and computer systems. The integrated transformer of the proposed converter consists of three step-down transformers on a single magnetic core. The z-parameter (gyrator) model and the equivalent-circuit model of the integrated transformer are derived. Based on the equivalent-circuit model, the principle of operation of the proposed converter is explained. The analysis and design criteria of the basic circuit, the operation of the regenerative LC snubber circuit, the simulation, and experimental verification are also described.