Secondary Control for Microgrids Using Potential Functions : Modeling Issues

The power system of the future is an intelligent grid capable of a number of functionalities. These functionalities will enable the power system to exhibit behaviours that enhance the reliability and security of the power system. This modern power system is called the smart grid. In order to ensure proper operation of the smart grid, it is important that its constituent parts operate satisfactorily. An integral part of the smart grid is a microgrid. Therefore, it is necessary that a control strategy for the microgrid in both grid-connected and islanded modes be devised. In this paper, a method for secondary control of microgrids is proposed to ensure their long-term stable operation under various load conditions and different configurations. In this method, a potential function is defined for each controllable entity of the microgrid, and a central controller devises the set of set points that optimize the overall operation of the microgrid.