PV-fed non-isolated resonant converter for DC microgrid applications

In this paper, a novel photovoltaic energy conversion system is presented for microgrid applications. The proposed system is a compact dc-dc converter consisting of a boost-type dual-resonant converter followed by a switching tank converter. This novel photovoltaic energy conversion system offers a robust and reliable operation with high efficiency. A boost-type dual-resonant converter is used as a maximum power point tracker that optimizes the match between the solar module and dc load. In the following, a switched tank converter (1-to-4 step-up configuration) boosts the output voltage of the dual-resonant converter to a higher output voltage for use in a dc microgrid. Comprehensive design steps and static analyses are reported to explain the dynamics of the proposed photovoltaic system. A 200-W laboratory-scale prototype was built to verify the theoretical framework experimentally. The detailed analyses are conducted to examine the system performance under steady-state and transient conditions. Experimental results are presented and discussed to explain the working principle of the proposed photovoltaic system.