Active clamped ZVS forward converter with soft-switched synchronous rectifier for high efficiency, low output voltage applications

Acik A., Cadirci I.

IEE PROCEEDINGS-ELECTRIC POWER APPLICATIONS, vol.150, no.2, pp.165-174, 2003 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 150 Issue: 2
  • Publication Date: 2003
  • Doi Number: 10.1049/ip-epa:20030151
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.165-174


The analysis, design, and implementation of an active clamped ZVS forward converter equipped with a soft-switched synchronous rectifier (ACFC-SR), proposed for high-efficiency low output voltage DC-DC converter applications, is presented. The converter efficiency is maximised due to soft switching of the main, active clamp, synchronous rectifier, and freewheeling MOSFET switches. The operating principles of the ACFC-SR are analysed in detail, and the converter performance is compared with that of alternative forward converter schemes employed in low output voltage DC-DC converters, in view of their power conversion efficiency. Experimental results are presented for a 50 W ACFC-SR converter with a DC input voltage of 48 V, an output voltage of 5 V, and operating at a switching frequency of 120 kHz. In general, good agreement is observed between the theoretical and experimental results.