Two-switch flyback-forward PWM DC-DC converter with reduced switch voltage stress

This paper introduces a two-switch flyback-forward pulse-width modulated (PWM) DC-DC converter along with the steady-state analysis, simplified design procedure, and experimental verification. The proposed converter topology is the result of integrating the secondary sides of the two-switch flyback and the two-switch forward converters in an anti-parallel connection, while retaining the two-main switches and the clamping diodes on a single winding primary side. The hybrid two-switch flyback-forward converter shares the semiconductor devices on the primary side and the magnetic component on the secondary side resulting in a low volume DC-DC converter with reduced switch voltage stress. Simulation and experimental results are given for a 10-V/30-W, 100 kHz laboratory prototype to verify the theoretical analysis.