Energy flow control of Wind/PV/Batteries/Supercapacitors autonomous hybrid power sources using the flatness concept

In this paper, an autonomous Wind/Photovoltaic (PV) hybrid power sources using lead-acid batteries and supercapacitors as storage elements is presented. The lead-acid batteries are used to compensate the power demand which PV and wind generators can't provide. Supercapacitors are employed to relieve the batteries of repeated charging and discharging ensuring longer hybrid source lifetime. The system is designed to supply a residential load. The exchanged power among different components is managed using a nonlinear control based on the flatness concept. Simulation results are presented and discussed for different wind speeds and solar illuminations.