Análise de desempenho e viabilidade econômica entre inversores do tipo string e otimizadores de potência instalados em sistemas fotovoltaicos sob diferentes condições de operação

Abstract

Renewable energy technologies provide clean energy obtained from natural resources, such as: the sun, water and wind. The technological development and the increasing competitiveness of solar photovoltaic energy systems have meant that the use of this source has shown considerable growth with the potential to become the most important source of electricity for energy systems in the future. The main challenge for the consolidation of solar photovoltaic energy is to reduce losses in energy conversion and increase its efficiency, in order to make it increasingly competitive in relation to other sources of energy. Power optimizers are modular c.c.-c.c. converters, whose function is to extract the maximum power from each photovoltaic module and optimize the energy conversion of the system. In this way, the optimizers help to mitigate problems related to adverse operating conditions, such as partial shading, in addition to eliminating losses due to mismatch. In this work, the design and modeling of a photovoltaic generation system was carried out using the computational tool Helioscope, where simulations are performed and the losses due to partial shading and electrical incompatibility between the photovoltaic modules are examined. The objective was, thus, to evaluate the impact of the use of power optimizers in systems subjected to shading conditions, compared to systems using the string inverter architecture, and to use this methodology to demonstrate the potential increase in energy production. As a result, in performance simulations, gains in the order of 8.86% to 10% were seen in generation efficiency. With the performance results in mind, an economic feasibility analysis is carried out through the software SAM (System Advisor Model). The results showed, through the analysis of the Levelized Energy Cost, that in the scenarios where there is the presence of shading, the energy cost of the systems that use power optimizers is equivalent to the energy cost of the conventional systems, which use string inverters.