Análise do controle por decaimento (droop control) aplicado em uma MR CA monofásica

Abstract

This work presents a study of a low-voltage islanded Microgrid operating in alternated current. The Microgrid is composed with three generation units and linear loads. Two generation units are dispatchable energy sources which have inverters working as grid-forming converters, it is utilized the droop control strategy for sharing power among the converters and maintain the Microgrid voltage stability. It was implemented a secondary loop control for restoring the voltage level and frequency degraded by the droop control. The grid-forming inverters are composed of Full-bridge voltage source inverters with a LCL output filter controlled as voltage. The third-generation unit is composed with a double-stage photovoltaic system which have four panels' series connected. In the first stage, the boost converter extracts the maximum power available on the photovoltaic array through the P&O method. On the second stage, the inverter work as a grid-feeding converter controlled as current which utilizes an algorithm a phase angle estimation algorithm to synchronize with the voltage at the common coupling point of the MR. It was used the MATLAB/Simulink® environment for designing, modelling and simulating the Microgrid. It was possible verify the droop control performance regarding the power sharing among the grid-forming converters in two situations, firstly it was not applied the loop secondary control, afterwards it was applied the loop secondary control. Besides it was possible to verify the grid-feeding converter on the Microgrid voltage, when it is connected to the Microgrid.