An active clamped two switch flyback Zeta converter with reduced switch voltage stress

This paper presents an active clamped two-switch flyback Zeta converter. The disadvantage of conventional flyback converters is the ringing caused by the transformer leakage inductance and the main switch parasitic capacitance resonance, resulting in high voltage stress on the switch. In the proposed converter, by using the active clamping technique, The voltage spike on the main switch is absorbed by the clamp capacitor, the voltage stress of the two main switches is clamped to V_in, and the switch operates in zero voltage switching, which can reduce the switching loss and improve the overall effectiveness. The converter proposed in this paper can reduce two diodes on the primary side of the converter compared with the traditional two-switch flyback converter. Finally, the simulation results of the 240W DC/DC prototype are presented to verify the feasibility.