| The two-transistor forward converter has many advantages, especially its low voltage stress, each power switches need to block only input voltage, so it is widely used in high voltage input application. The interleaving two-transistor forward converter succeeds to the advantages of the two-transistor forward converter, it has two units working alternately, the power loss of the converter is distributed and the output voltage ripple frequency is twice of the switching frequency. Compared with full-bridge or half-bridge converter, a two-transistor forward converter has no risk of direct break-through in the two transistors of the same leg, it is suitable for high voltage input high power output application.In this paper, the working principle of the interleaving two-transistor forward converter is analyzed in detail, and the waveforms of the switch drain-to-source voltage and transformer magnetizing current are researched in different duty cycle conditions. The simulation model is constructed and the simulation results verify the analysis. The peak current control principle and its realization circuit is researched, the small signal model of the peak current controlled interleaving two-transistor forward converter is constructed and the system transfer functions is presented. Then the system stability is analyzed through frequency simulation with matlab. Finally, a 3KW prototype is build and the design method of the power circuit and control circuit is presented, the experimental results verify the analysis.
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