Hierarchical control of intelligent microgrids

Worldwide, electrical grids are expected to become smarter in the near future. In this sense, there is an increasing interest in intelligent and flexible microgrids, i.e., able to operate in island or in grid-connected modes. Black start operation, frequency and voltage stability, active and reactive power flow control, active power filter capabilities, and storage energy management are the functionalities expected for these small grids. This way, the energy can be generated and stored near the consumption points, thus increasing the reliability and reducing the losses produced by the large power lines. In this article, the main concepts related to the configuration, control, and energy management of intelligent microgrids are reviewed.