Double line frequency pulsating power has always been a major issue for single phase inverters and rectifiers. While traditional solution of bulky DC bus capacitor can filter out the inherent double frequency harmonic of single-phase inverters, its physical size and high failure rates are often undesirable, especially for applications that demand small volume and weight and high reliability and efficiency. In this paper a novel soft-switching single-phase AC to DC topology, which absorbs the pulsating power with a small film capacitor, is proposed. This eliminates the need for bulky DC bus capacitor. The proposed topology uses an active auxiliary structure to achieve soft switching for all main switches across the full load range. This lowers the power loss, volume and weight. In this digest simulation results and mathematical analysis are presented to better explain the operation of the system. Preliminary experimental results are also presented. Complete experimental results will be presented in the full paper.
