Arquitetura de controle para limitação de exportação de potência em inversores fotovoltaicos utilizando automação aberta em microrredes

Abstract

This work presents the development and experimental validation of an active power control architecture for photovoltaic microgrids, aiming to implement Grid Zero (zero export) operation in grid-tied inverters. The initial motivation is based on the need to adapt photovoltaic systems in facilities with maximum energy export limits due to the saturation of the local electrical infrastructure capacity, a characteristic scenario of the IFG Itumbiara Campus. To solve this problem, a control loop was developed based on an open-source automation architecture orchestrated in Docker containers: Node-RED acted as a communication gateway (converting Modbus TCP to MQTT), while Home Assistant executed the control logic and the operation interface. Tests performed on the microgrid, composed of Fronius and Victron inverters, demonstrated that the system was able to raise the self-consumption rate to levels above 94%, eliminating the continuous export of energy. The results validate the proposed architecture as a low-cost and replicable solution for efficient energy management under injection constraints.