PV-STATCOM para o Controle de Tensão em Redes de Distribuição de Baixa Tensão sob influência da geração fotovoltaica

Abstract

The installation of photovoltaic power plants as distributed generation has grown in recent years. However, its large-scale insertion into the secondary distribution network can cause some power quality issues, such as overvoltage and voltage fluctuations beyond acceptable limits. A promising strategy to control these voltage limit violations is by controlling the reactive power supplied or absorbed by photovoltaic inverters, which start to operate as PV-STATCOM. This article presents the performance of a photovoltaic inverter for voltage control in a secondary distribution network based on reactive power dispatch. The inverter has 100 kVA of nominal apparent power and is installed in the Universidade Federal do Paraná (UFPR) Electrical Engineering building, powered by a 350 kVA transformer. The programming and implementation of the reactive power control were carried out using a Programmable Logic Controller (PLC). Two tests were carried out to analyze the voltage and reactive power response of the inverter. In the first test, the PV-STATCOM performed well in controlling the reactive power to reduce and increase voltage at the point of common coupling (PCC) in accordance with established reference voltages. A 5 V voltage variation at the PCC was produced as a result of 25 kvar of absorbed reactive power. In the second test, PV-STATCOM was able to minimize voltage fluctuations resulting from the intermittency of photovoltaic solar generation, limiting the voltage variation at the PCC to a range of approximately 5 V.