Design and implementation of boost-zeta module-integrated converter for PV power applications

The Future Renewable Electric Energy Delivery and Management (FREEDM) Systems Center was recognized with the mission to improve the fundamental and permitting technologies essential for model ever-changing power grid infrastructure, the FREEDM System. Aiming to reduce this system costs and improve its reliability and modularity, this paper proposes an improvement in the FREEDM topology. It consists in the removal of the DC-DC battery charger (DESD) converters and replaces them by the direct connection of a single battery bank to the DC bus. This way, only Distributed Renewable Energy Resources (DRER) converters are employed with a single battery bank ensuring that quite a lot of hardware is saved. Nevertheless, to maintain the battery charging regulation, the DRER converters, besides the maximum power point tracking (MPPT), must also to run the battery charging method and to provide adequate charging conditions to the single back-up system. To achieve such characteristics a novel single-switch DC/DC converter is presented and analyzed. This converter provides high voltage gain and low output current ripple required for the new DRER functionalities, which is responsible for the MPPT of the PV module and also the Constant Current, Constant Voltage (CCCV) charging method of battery pack. Experimental and Simulation results are presented for the purpose of operating the converter and also the operation of the system.