Effect of optocoupler feedback dynamics on peak current mode controlled active clamp forward converter

Forward converter has been used in low and medium power applications due to the cost effectiveness, simplicity, wide input and output variation. Many reset techniques are developed to reset the transformer magnetizing current and increase the duty cycle range of the switch. Active clamp reset technique has the advantage of both increased operating duty cycle and zero voltage switching resulting in increased efficiency. Since it is an isolated converter, optocoupler feedback has been used to isolate input and output. Due to the design simplicity it is being widely used in telecommunications and military applications over magnetic feedback. This paper presents the comparative study of type-II controller realization with Operational Amplifier and optocoupler isolation for 48W peak current mode controlled active clamp forward converter with self-driven synchronous rectification. The effect of optocoupler dynamics is investigated for the closed loop active clamp forward converter with the PSPICE simulation.