Design and Analysis of Photovoltaic-Fuel Cell Hybrid Distributed Generation System

This paper proposes a hybrid system consisting of photovoltaic and fuel cell to realize a reliable power supply for a grid connected critical load. The designed system ensures maximum utilization of the photovoltaic array, and necessary utilisation of fuel cell stack thus providing optimum operational costs. Both the sources are operated independently or in conjunction as per requirement. The sources are first connected to a common DC-link through separate DC-DC converters and then to the grid through a common inverter. The inverter power angle is controlled to maintain a constant DC-link voltage to ensure complete power transfer and the inverter modulation index is controlled to maintain the reactive power requirement of load. The inverter control also provides harmonic compensation for any non-linear load connected at the point of common coupling thus maintaining the grid current free of any distortions because of the load.