Investigation of PWM controlled, resonant transition converters with asymmetrical duty cycle

Investigations on a specific group, asymmetrical duty cycle controlled power converters, which belong to the class of resonant transition topologies are presented. A detailed analysis following a state-graph strategy is given, revealing three modes of operation, Various design equations are derived representing the equipment for a consolidated design of a 300 V-5 V/60 A DC/DC power converter, switched at 500 kHz. The high measured efficiency of 86% at rated power and up to 89% at half load, resulting from the high turns ratio and low reactive power, proves this switching technique favorable as compared with other soft switching techniques of the last decade by eliminating switching losses without a rise in conduction losses.