A novel pulsewidth control scheme for fixed-frequency zero-voltage-switching DC-to-DC PWM bridge converter

A new gating pulse scheme is proposed for the control of DC-to-DC pulsewidth-modulated (PWM) bridge converter that provides zero-voltage switching (ZVS) for all the switches for a wide variation in load and input voltage. This new complementary fixed-edge gating control scheme is compared to the traditional phase shift control scheme. Modes of operation are presented and analyzed. Based on the analysis, design procedure and design curves are obtained. An optimum design is given and a design example is presented. Results obtained from PSPICE simulation for the converter designed are given to verify the performance of the proposed converter for varying load as well as line voltage. Detailed results obtained from a 500 W experimental converter are given to verify the advantages of the proposed gating scheme.