Abstract：Active clamped asymmetrical dual switch forward (ACADSF) converter is a preferable candidate standard DC/DC module for high line and wide range input application in low to medium power rating systems. To make the ACADSF be more suitable for practical applications, a novel ACADSF converter is proposed, which, compared with original ACADSF, maintains the advantages that duty cycle can be more than 50% and ZVS transition for all switches under all conditions, while only one auxiliary switch is needed to reset transformer and which improves efficiency and simplifies circuit configuration as well. Therefore, the proposed topology has more strong capability than the original type for high line and wide range input practical industrial applications where high efficiency requirement is tense. The detail operation principles, as well as the design considerations, are presented. A prototype aiming at telecom system of 200～400V input, 54V output, whose highest conversion efficiency is 97%, is built to verify the validity and applicability of this topology.
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2009, Vol. 24 
