Fully-dispatchable microgrid: Architecture, implementation and experimental validation

The paper describes a fully-dispatchable microgrid architecture that features i) the adoption of a master/slave power-based control in the central dispatcher to drive distributed power generators and ii) the connection of a suitable power converter equipped with energy storage, called Utility Interface, at the point of common coupling with the mains. Property i) ensures scalability and capability to drive distributed units at low bit rate and without synchronization or knowledge of grid parameters, thus avoiding the use of information that may be difficult to retrieve. Property ii) allows optimum behavior at the utility terminals, by providing compensation of load unbalance, reduction of harmonic injection, fast reaction to load and line transients, and prompt response to utility demands. In addition, the proposed solution allows plug-and-play integration and full utilization of distributed energy resources, balanced power sharing among distributed generators, and stabilization of voltage profiles. After a presentation of the microgrid architecture, the paper describes the implementation of a robust control strategy providing the above functionalities and its validation in a laboratory-scale microgrid prototype.