Analysis, Design, and Simulation of a Dual Active Bridge for PV-based Residential Nanogrids

In this paper, theoretical modeling, design and numerical simulations are presented for a dc-dc dual active bridge (DAB) converter in a Phtovoltaic (PV)-based nanogrid. Different tasks in the nanogrid are performed using the same topology. A case study of a nanogird with three PV modules connected to a regulated dc bus using three DAB converters will be considered. For these DAB converters, the input voltage is controlled based on natural sampling fixed frequency pulse width modulation. The dc bus is regulated by using a grid-connected dc-ac inverter injecting the harvested PV power to the grid while performing active power quality control. The dc bus is also connected to a storage battery through a bidirectional DAB converter operating as a battery charger/discharger. The Numerical simulation results show the validity of the mathematical model and the capability of the DAB converter to perform all the previous tasks in a PV-based nanogrid.