On the design of aggregators for microgrids providing active and reactive power services

Given the spread of distributed generation, new coordination mechanisms are needed to maintain the efficiency and the safe operability of the electricity network. MicroGrids (MGs) are an interesting solution to locally manage generators but they cannot singularly give a significant contribution to sustain the overall grid system. In this paper we proposed a coordination framework for aggregation of interconnected MGs to provide extra ancillary services to the main utility. Through the use of distributed optimization algorithms and equivalent modelling techniques, the proposed optimization approach is computationally efficient despite the large size of the problem, and it ensures that the MGs internal information and management strategies are not externally shared.