A minimização da severidade de afundamentos de tensão com a injeção de reativos em sistemas fotovoltaicos conectados à rede elétrica

Abstract

Considering the growth of the global market for intermittent renewable energy sources (eg solar and wind) in recent years in Brazil and the World and their integration in electrical power systems, recurrent concerns arise with aspects related to power quality, mainly with the growing demand for distributed generation facilities or large photovoltaic systems. When these systems are installed on a large scale in the distribution system, they can bring benefits to the system as a whole through its ancillary services such as: active and reactive power injection, harmonic control and power factor, causing positive impacts. In this context, the improvement of power electronics in static converters and the use of storage systems have brought interesting options in order to minimize such impacts, offering the possibility of minimizing some disturbances resulting from voltage sags and the generation of undesirable harmonics. Given this scenario, this work aims to analyze the impacts of voltage sags that can be caused by faults, unbalanced loads, varied load profiles and the use of distributed photovoltaic generation to minimize the severity of sags through the injection of active and reactive power through static converters, mainly those used in photovoltaic plants (USF) connected to the power grid. The methodology of this work consisted of bibliographic review on the subject, mathematical modeling and computational simulations using the PSCAD software, in which three circuits were simulated and producing graphs and tables presenting the results for each simulation performed, in order to assess the disturbances and their possible minimization or mitigation.