Wide area monitoring and control for voltage assessment in smart grids with distributed generation

In this paper, the application of wide area measurement and control for voltage assessment of hybrid AC/DC smart grid is investigated. The power available from renewable energy assets and storage elements on the microgrids is utilized to maintain system voltage stability. The system under study consists of two DC microgrids coupled to a multi-bus AC system. The supervisory controller of each of the two microgrids continuously communicates with the main controller of the AC grid, sending the available amount of apparent power and receiving power commands. The AC grid is monitored and controlled using a wide area measurement system in which measurements of the different nodes in the system are synchronized to a unified pulse signal. In case of voltage violation at any of the buses, the minimum reactive power needed from each of the micrgrids in order to restore the voltage magnitude to a value that is between the permissible limits is determined in real time by solving an optimization problem. Simulation, as well as experimental, results are included to verify the validity of the proposed wide area control technique.