This paper presents a point of common coupling voltage regulation technique by using a photovoltaic power plants generation system for controlling not only the injection active power but also the balance reactive power. The need of this functionality becomes true when some countries propose the use of renewable energy to help the grid when a sag is detected as a new standard. However, the idea is extensible to Smart-Grids where the power balance must be provided by the distributed generation. Active power injection is developed by a reference power point tracking and reactive power regulation by controlling the node voltage, both with dq current control with the different power priority possibilities. The studied topology is based on a single-stage traditional inverter but the control algorithm philosophy is valid for any topology. The whole system has been simulated in order to validate the control algorithm and tune the controller for obtaining the best transient response with zero steady state.