Estudo e aplicação dos controladores Pi, Pi+R, preditivo e repetitivo em um sistema fotovoltaico conectado à rede elétrica monofásica

Abstract

This work presents a comparative study of the PI, PI + Resonant, PI + Repetitive and Predictive controllers, applied to a dual-stage photovoltaic system (PV) connected to a single-phase power grid. The PV system is composed of a cc-cc boost converter cascade with a single-phase full-bridge inverter. The first stage is responsible for tracking the maximum power and for performing the PV array voltage rise. On the other hand, the second stage is used to inject all the active power drained from the PV array in the single-phase power grid. The extraction of the maximum power is realized using the algorithm of Perturb and Observe (P&O), which generates the voltage reference used in the multi-mesh control system applied to the boost converter. The studied controllers in this work are used to control of the current injected into electrical grid, and are compared taking into account their efficiency in the traceability of the reference signal, steady state oscillation and harmonic distortion rate of the injected current. The photovoltaic system was implemented in computer simulation tools and form the obtained results the comparison of the controllers was carried out considering: (i) ideal electrical grid (ii) electrical grid with harmonic voltage distortion.