Abstract：In this paper, a new rectifier topology is proposed. It is used in an interleaved active-clamp forward converter with series-parallel auto regulated secondary windings. With the proposed topology the secondary side of the two interleaving channels works in series when the input voltage is low and the steady state conversion gain of the converter can be improved. The maximum duty cycle can be extended to be larger than 0.5. The steady state of secondary side windings are determined by duty cycle of the converter. Accordingly, the current stress of primary side can be reduced by using interleaving structure. And the voltage stresses of secondary side are reduced by the proposed rectifier as well as the current ripple in the output filter inductor. A 240W prototype is built up to verify the theoretical analysis.
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2010, Vol. 25 
