Abstract：It is difficult to achieve zero-voltage for the basic phase-shift full-bridge zero-voltage switching converter’s lag leg at light loads, so that the scope of soft-switching is considerably limited. At the same time, rectifier diodes exist seriously voltage overshoot and oscillation. In this paper, the active-clamp snubber circuit is proposed at rectifier diodes in parallel, that it can effectively control the rectifier diodes voltage overshoot and oscillation. The active-clamp snubber circuit loss is relatively small, so as to ensure high efficiency converter. Series saturation inductance in the primary transformer can effectively expand the range of zero-voltage switching of the load using critical characteristics of the saturation current. Theoretical analysis and experimental results show that it is to achieve the lagging leg for using secondary active clamp and saturated inductance of new zero-voltage full-bridge converter.
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2011, Vol. 26 
