A novel two-quadrant soft-switching converter with one auxiliary switch for high-power applications

This paper describes a newly proposed two-quadrant soft-switching (SS) converter with only one auxiliary switch suitable for various high-power applications. The proposed converter realizes SS using a simple load-side auxiliary resonant tank that consists of a switching device, a diode, and an inductor. With a novel fixed-timing control scheme, the resonant current varies with the load current to achieve near zero-voltage turn-on and lossless snubber turn-off at all current conditions. There is no need for any sophisticated control algorithms and sensors. Computer simulation and hardware implementation were performed with a 15 kVA converter to validate the proposed converter. A comprehensive evaluation indicates that the SS gains significant benefits over the conventional hard-switching counterpart.