The photovoltaic industry is present everywhere in the world, but there is a clear concentration in the industrialized countries. As part of their energy strategy and given their dependence on the outside for the energy supply, industrialized countries give priority to the development of renewable energies and sustainable development, including photovoltaic (PV) energy. This work aims to facilitate the approach of this fascinating and promising technology: it concerns the coupling of PV systems to the utility grid from the control/synchronization point of view. For this purpose, this work presents the modeling and control of a three-phase inverter for grid-connected PV system, an improved digital PI current control algorithm is used to remain the current injected into the grid sinusoidal and a performance synchronous reference frame Phase-Locked Loop (dqPLL) is used as the synchronization technique.