Advanced Control and Management Functionalities for Multi-MicroGrids

Abstract

This paper addresses the extension of the Microgrid concept, following a massive integration of these active cells in power distribution networks, by adopting a coordinated management strategy together with Distributed Generation units directly connected to the Medium Voltage distribution network. In order achieve this, a technical and commercial management scheme must be developed for coordinated control of a distribution system with Multi-Microgrids, which should take into account the specific technical capabilities and characteristics of each type of generating source. In particular, tools for coordinated voltage support and frequency control, as well as for state estimation have been developed for this type of networks. Concerning voltage support, a new methodology exploiting an optimization tool based on a meta-heuristic approach was developed. For state estimation, two approaches were considered: Multi-Microgrid State Estimation and Fuzzy State Estimation. Regarding frequency control, the hierarchical structure of the Multi-Microgrid is exploited to deal with the transition to islanded operation and load following in islanded operation. All these tools have proved to be efficient in managing the Multi-Microgrid system in normal interconnected mode and, in case of the frequency control, in islanded operation.