MODEL ANALYSIS AND SYSTEM DESIGN OF INTERLEAVING DOUBLE-TRANSISTOR-FORWARD CONVERTER

Based on the operating principle of interleaving double-transistor forward converter, this paper analyzes two operation modes of converter and the reset of transformer magnetizing in different duties. The analysis reveals that the resonance in the reset processing magnetizing will not cause the increase of voltage stress in switching. The small-signal model is set up with average circuit method. The compensator and its parameters of output-voltage-feedback control are analyzed carefully and presented. The experiments of the prototype show that the operation mode of interleaving double-transistor forward converter is quasi-square-waves. Therefore, the conventional constant-frequency PWM control can be applied here and the conclusion is important for simplifying the control strategy. The experiment results coincide with the theoretical analysis and the validity of analysis approach is proved.