Current-Fed Flyback Push-Pull DC-DC Converter Based on Three-Phase Transformer

Three-phase current-fed flyback push-pull dc-dc converter is proposed in this paper, which is a new circuit topology putting into practice based on current-fed flyback push-pull dc-dc converter. Structure is simplified; cost is cut down; efficiency and reliability are improved all by the high frequency three-phase transformer technique that carries out functions of flyback transformer as well as push-pull transformer at the same time. Three-phase transformer can be separated into relatively independent functions of flyback transformer and push-pull transformer with the reluctance produced by the magnetic gap in the central phase; the flyback transformer produces only common-mode flux in the magnetic circuit of push-pull transformer and does not influence its output signal; the magnetic flux in push-pull transformer is blocked by the magnetic gap and can only flow through the outer magnetic loop. Investigational device is designed; static and dynamic characteristics are observed and test results are verified by the experimentation.