Control strategy for photovoltaic-wind Hybrid System using Sliding Mode Control and Linear Parameter Varying feedback

Abstract

Photovoltaic-wind Hybrid Power System (HPS) presents an interesting solution in Renewable Energies development. However, in order to maximize energy production, associate control strategy must manage Maximum Power Point Tracking (MPPT) for each source as efficiently as possible. This paper proposes an original control strategy for a stand-alone photovoltaic-wind HPS with batteries storage, also applicable to grid-connected systems. An individual Multi-Inputs Multi-Outputs (MIMO) controller is applied to each power source. The photovoltaic generator is thus managed by Sliding Mode Control (SMC), including an internal MPPT algorithm, whereas the wind generator employs a Linear Parameter Varying (LPV) state feedback control, designed by Linear Matricial Inequalities (LMI), and combined with a MPPT algorithm. Perturbations between sources output currents, and control strategy performances, have been verified in simulations: such a control is able to follow quickly each generator's Maximum Power Point despite their coupling.