Decentralized Real-Time State Estimation in European-Type LV Grids: An Implementation Using Edge Computing

The pervasive use of advanced communication technologies in industrial facilities puts them in an excellent position to pioneer the active management of distribution grids. As these grids become increasingly complex, only a decentralized state estimator with a swift responsiveness can allow for a proper flexibility management, and thus, for an adequate use of distributed generation and energy storage systems. Addressing the lack of current solutions tailored for 4-wire unbalanced LV grids, i.e., European type, this proposal presents the implementation of an edge computing device, aimed at the terminal transformer level, which can perform distribution state estimation at a low cost. The state estimator, optimized to run on the edge device, solves the state estimation problem using the modified augmented weighted least squares method. Additionally, this work introduces a grid emulator designed to mimic the distribution grid, providing field measurements, and facilitating communication with the edge device via Modbus TCP/IP, for evaluation purposes. To validate the effectiveness of this implementation, a comprehensive set of tests was conducted using the model and data of a real LV grid in Spain. The results showcase not only good accuracy but also a remarkably fast execution time. These facts affirm the suitability of this cost-effective embedded solution for achieving real-time estimation, making it highly useful for higher-layer applications.