Control of a Photovoltaic System Connected to Grid

Abstract

In this paper, we are interested in the quality of the electrical power supplied by a PV system connected to the grid, in terms of control of the current injected into the grid, as well as the control of the voltage at the point of common coupling. The proposed model introduces current and voltage cascade regulation loops based on conventional controllers type PI, which make it possible to regulate DC link voltage, to stabilize the voltage at the point of common coupling (PCC) on the AC side of the inverter, and to maintain the injected current to the grid in phase with the voltage. In order to demonstrate the feasibility and the effectiveness of the suggested control a simulation using the Matlab/Simulink software has been performed, to confirm that the proposed control model, is able during the permanent and transient operating conditions, of injecting an optimal power to the grid, with a unit power factor, while keeping the stable voltage at the point of common coupling, without exceeding the grid code requirements.