Experimental validation of differential flatness-based control applied to stand alone using photovoltaic/fuel cell/battery hybrid power sources

This paper proposes an experimental study of a control strategy for a voltage regulated DC hybrid power source employing photovoltaic (PV) panels as the main source, fuel cell (FC) emulator as the auxiliary power source and lead-acid batteries for the reason of storage and to ensure the right balance between the distributed generation system and the load. This approach is based on the DC link voltage regulation; wherever the energy generated is managed through this nonlinear approach based on the differential flatness property. In addition, the entire description of the state's trajectories can be obtained using this control technique, in which improvement of the dynamic response, stability and robustness of the proposed PV-FC hybrid system by decreasing the static error in the output regulated voltage all has been taken into account in this work. The experimental results show that the proposed control based on the flatness theory is able to manage well the power flow in a hybrid system with photovoltaic, fuel cell and lead-acid batteries.