Constant-frequency zero-voltage-switched multi-resonant converters: analysis, design, and experimental results

The multi-resonant-switch concept is modified to provide constant-frequency operation. Complete DC analysis and designs of the constant frequency forward and half-bridge multi-resonant converters are presented. Different implementations for the half-bridge topology are discussed. The performances of a 50 W forward converter and a 100 W, offline, half-bridge converter are also presented. A significant constant improvement of the performance of the constant-frequency zero-voltage-switched multi-resonant converter is expected from the development of MOSFETs with very low on-resistance (synchronous rectifiers).