Predictive Direct Power Control of Grid-Connected PV Systems

Abstract

This paper presents an effective grid-injected power control method for photovoltaic (PV) systems based on the theory of model predictive control (MPC). Future values of the grid-injected active and reactive power can be predicted by using the discrete-time model of a grid-connected two-level voltage-source three-phase inverter. The grid-injected active and reactive power can be conveniently controlled by minimising a defined cost function of active and reactive power reference for optimally selecting the switching states of the inverter. The main advantage of this control method is that it does not require the use of any current controllers or modulators. The simulation results obtained using MATLAB/Simulink verify the effectiveness of the proposed method.