Parametrização de circuitos elétricos equivalentes com algoritmo twiddle para rastreamento de máxima potência no aproveitamento fotovoltaico de energia

Abstract

Given the growing relevance of energy production based on renewable sources with a lower environmental impact, this work aims to develop and validate models for the optimization of photovoltaic systems, addressing everything from the modeling of generators to the control of converters DC-DC and DC-AC used in the integration of these systems into final consumption. The study begins with the modeling and parameterization of photovoltaic generators, where equivalent electrical circuits are presented, with an emphasis on the single-diode model with series and parallel resistances, to accurately simulate the behavior of photovoltaic cells, modules, and arrays under different operating conditions. Next, techniques for Maximum Power Point Tracking (MPPT) are introduced and discussed, with the main function of ensuring that photovoltaic systems operate at maximum efficiency, considering the environmental conditions to which they are subjected. Using DC-DC converters, such as the boost converter, the implementation and analysis of results based on the “Perturb and Observe” method were addressed, highlighting the development of a current PI controller coupled with an MPPT algorithm to ensure greater system robustness. The simulations performed for these configurations demonstrated the potential efficiency in optimizing energy extraction from photovoltaic arrays. Finally, the work addresses the use of inverters in DC-AC energy conversion, which is crucial for the integration of photovoltaic systems into loads powered by alternating current. Among the topologies discussed in the literature, the inverter based on the three-state switching cell (3SSC) was adopted, whose characteristics facilitate the filtering of harmonic distortions and consequently improve the quality of the generated energy. The simulation results demonstrated significant success in photovoltaic energy utilization with a five-level alternating voltage, without relevant power dissipation in unwanted harmonic components.