Control of PV-FC-Battery-SC hybrid system for standalone DC load

This paper presents a hybrid system comprise of Photovoltaic (PV), Battery, Supercapacitor (SC), Fuel Cell (FC) to meet isolated DC load demand. The PV is the primary energy source, whereas battery and SC both are considered for their different power density to supply transient and steady load respectively. To increase the reliability of the system the fourth source FC has been chosen to keep the battery fully charged. All sources are connected to DC bus by different DC-DC converters. A power flow control strategy adapts their variable DC voltage to Bus voltage by means of these converters. In this work, FC is chosen to work for a limited period. This will avoid the over sizing of the FC and limit the operational cost of the system. The whole energy management principle has been validated in MATLAB/SIMUINK with variable load demand and solar radiation profile.