A LCL-resonant isolated multiport DC-DC converter for power management of multiple renewable energy sources

This paper proposes a new LCL-resonant, isolated, multiport, DC-DC converter for power management of multiple renewable energy sources. The proposed converter has the advantages of simple topology and using minimum number of power switches since it only uses one controllable switch in each port to which a source is connected. The proposed converter contains a LCL-resonant circuit to make the main switch work under zero-current switching (ZCS) and zero-voltage switching (ZVS) conditions. Compared to the corresponding hard-switching converter, the proposed converter has a lower voltage stress across the main switch and higher efficiency. The proposed converter is capable of simultaneous maximum power point tracking (MPPT) for multiple renewable energy sources, which can be of different types, capacities and voltages. Experimental results are provided to validate the proposed converter for MPPT control of a solar system consisting of three different photovoltaic (PV) panels.