A soft-switched AC-to-DC converter operating in DCM: analysis, design, simulation and experimental results

摘要

A soft-switched AC-to-DC converter cell operating in DCM is proposed. Operating principle and various operating intervals of the converter are presented and analyzed. Design procedure is illustrated with a design example of a 1 kW AC-to-DC converter cell operating on a 165 to 265 V rms utility-line and switching at 100 kHz. Loss calculations are included. Based on the design example, operation and performance of the converter is verified using SPICE simulations. Detailed experimental results obtained for the designed converter employing warp-speed IGBTs are presented. This converter has low line-current THD and has a measured efficiency of about 95% and will be used as cells of a multi-phase 5 kW converter.