A Zero-Voltage-Transition Auxiliary Network for Central Capacitor Partial Power Processing DC/DC Converter

This paper proposes a zero-voltage-transition (ZVT) auxiliary network for the central capacitor partial power processing (CCPPP) DC/DC converter, which can be used to boost two or more input sources. Compared to the commercial dual-boost converter, the CCPPP topology announces higher efficiency and lower cost by reducing both voltage and current stresses of semiconductors without extra devices. The proposed ZVT auxiliary network further enhances the operational efficiency by means of providing zero-voltage-switching (ZVS) to main transistors and main diodes, also all the auxiliary diodes operate at soft-switching. These unique features make this ZVT integrated CCPPP converter equipped for the front-end DC/DC stage of distributed photovoltaic (PV) inverter. This paper presents an introduction of partial power processing concept and the detailed operational principle of the proposed ZVT network. In addition, the design procedure is elaborated. Finally, the proposed circuit is verified through a 1700W/360V experimental prototype.