A soft switching flyback current-fed push pull Dc-Dc Converter with active clamp circuit

In this paper, an active clamp circuit is applied to a flyback current-fed push pull converter to limit the voltage stress across the switch due to transformer leakage inductance. In addition, this clamp circuit provides soft switching condition for all switches. This allows the designer to increase the switching frequency in order to reduce the converter size. The proposed converter operates under zero voltage switching in both buck and boost modes and increases efficiency and reliability. Implementation of control circuit is very simple since the converter is PWM controlled and the auxiliary switches turn on complimentary with main switches. The converter operating modes are analyzed and in order to verify the converter operation, simulation and experimental results are presented.