Bancada para ensaios de sistemas fotovoltaicos conectados à rede elétrica monofásica empregando emulador eletrônico fotovoltaico

Abstract

This work presents the analysis, development and implementation of a workbench for testing and study of photovoltaic (PV) systems, which is distributed in four stages of power conversion. The input stage consists of a single-phase rectifier, which drains sinusoidal current from the electrical network in order to provide a continuous voltage for the first DC-bus. In the second stage, a DC-DC converter (Buck) is used, which is controlled to emulate and reproduce the characteristic curves of a specified PV module. The third stage features a Boost DC-DC converter, which has the function of performing the Maximum Power Point Tracking (MPPT), as well as to supply energy to the fourth stage (second DC-bus). Finally, all the energy available on the second DC-bus is injected into the mains by means of a single-phase inverter. In this way, the photovoltaic bench allows the study and analysis of the four power stages used, in addition to allowing the analysis of different MPPT algorithms. The mathematical modeling of each power stage, as well as the design of controller gains are also presented. By means of simulation results and experimental tests the presented system performance is evaluated, analyzing the static (steady-state) and dynamic behaviors of each power stage, in order to validate the study.