Inversores fotovoltaicos multifuncionais: análise da capabilidade durante compensação harmônica

Abstract

Increased attention has been given to distributed energy generation growth provided by renewable sources. Among the dierent possibilities of expansion, one of the sources with great focus in the current scenario is the photo voltaic energy. The electronic power converters perform a key role in these connected to the grid systems. The main objective of a photovoltaic inverter is to inject the photovoltaic power into the ac-grid. Generally, due tovariations in solar irradiance, inverters operate bellow their rated current. Therefore, this current margin can be used to ancillary services, such as harmonic current compensation. Hence, this work evaluates the eects of theseauxiliary services on the operation of the systems. Through mathematical modeling and computational simulation, it was possible to correlate the harmonic current compensation with the appearance of energy oscillations inthe DC bus. Furthermore, a comparisons between four dierent techniques of maximum power point trackers were perform. In addition, the behavior ofan LCL lter connected to the grid during harmonic current synthesis was analyzed. For this study, an algorithm was developed that estimates the limitations imposed by the DC bus in the compensation of harmonic currents due to the voltage drop in the passive elements of the lter. The results showthat although multifunctional inverters signicantly improve the quality of electrical energy, precautions are recommended due to severe changes in the operation of the photovoltaic system.