Análise e controle de um sistema fotovoltaico conectado à rede elétrica com mitigação de harmônicas e armazenamento de energia

Abstract

This work presents the analysis and control of a single-phase grid-connected photovoltaic system with integrated energy storage and harmonic distortion mitigation. The proposed system consists of a photovoltaic array connected to the direct current (DC) bus through a DC–DC Boost converter, an energy storage system based on batteries associated with a bidirectional Buck–Boost converter, and a Full-Bridge DC–AC inverter responsible for interfacing with the electrical grid. As a strategy to improve power quality, different passive filter topologies, namely L, LC, and LCL, were investigated and compared regarding their effectiveness in reducing harmonic distortions produced by the inverter. The adopted methodology was based on mathematical modeling, controller design, and computational simulation using PSIM software under different operating conditions to evaluate electrical performance, DC bus regulation, and power quality indices. The impacts of filter insertion on the injected current waveform and on the overall system performance were analyzed. The results demonstrated that all evaluated topologies contributed to reducing the Total Harmonic Distortion of current (THDi), achieving values of 3.77% for the L filter, 2.20% for the LC filter, and 1.94% for the LCL filter, highlighting the superior performance of the latter configuration. Additionally, the system achieved a power factor of up to 0.9999 and maintained the DC bus voltage regulated at 400 V, indicating satisfactory control performance and proper integration among photovoltaic generation, energy storage, and grid connection. It is concluded that the combined use of control techniques and passive filtering contributes to improving power quality and enhancing the operational performance of grid-connected photovoltaic systems.