A Single-Phase dc-ac Dual-Active-Bridge Based Resonant Converter For Grid-Connected Photovoltaic (PV) Applications

This paper presents the topology, modelling and control strategy for a single-phase grid-connected converter for photovoltaic (PV) applications based on the series-resonant dual active bridge (DAB). A state space large-signal model is derived for phase-shift based modulations, and a linearized model is presented for control design. A multi-loop control strategy is presented where a current-control loop regulates the current that the converter injects in-phase with the grid voltage, while a slower loop regulates the PV array voltage for MPPT. To verify the model and control strategy, simulation and experimental results are presented