Differential Flatness-Based Control of a Stand-Alone Solar-PV Energy Generating System

This paper presents an energy management approach for a microgrid based on the use of a hybrid storage system. The studied system comprises a PV solar source, Ultra Capacitors (UC) and a battery pack, designed for supplying a residential load via a common DC bus. The UCs are used to cope high frequency variation of the load, such as in transient state, while the batteries are in charge of slow load /source variation. Nonlinear flatness-based controllers are used to stabilize the electrostatic stored energy the UCs that allows to control the DC bus voltage indirectly. The proposed control system has a good performance to face correctly the source/load variation. The whole system, is first modeled. The simulations by using Matlab are then carried out which confirm the good performances of the proposed energy management and associated control system.