Modeling and control of a gird connected PV generation system

This paper presents the analysis, modelling and control model of the electric part of a grid connected photovoltaic generation system. The model contains a detailed representation of the main components of the system that are the solar array, and the grid side multilevel neutral point clamped (NPC) voltage source inverter (VSI). In order to extract the maximum amount of from the photovoltaic generator, we propose an intelligent control method for the maximum power point tracking (MPPT) of a photovoltaic system under variable temperature and insulation conditions. This method uses a fuzzy logic controller. As part of our work, we will focus on voltage inverter at three levels to NPC structure. The latter can increase the voltage supplied to the load (network) through their topology. Thus, they can generate more voltage sinusoidal possible and improve the total harmonic distortion through the high voltage levels provided by the structure of this new converter. The grid interface inverter transfers the energy drawn from the PV module into the grid by keeping common dc voltage constant. The PQ control approach (Direct Power Control) has been presented for the multilevel inverter. The simulation results under Matlab/Simulink show the control performance and dynamic behaviour of grid connected photovoltaic system.