Real-time Economic Dispatch and power management in microgrids

An optimal Economic Dispatch is the ability to distribute the demand among the generating units to minimize the total generation cost while meeting the system's equality and inequality constraints. One way of performing economic dispatch on a system is through the use of Day-ahead unit commitment and Day-ahead spot market. However, the day-ahead approach does not guarantee the optimal operation of the grid. Furthermore, this approach does not allow the integration of intermittent renewable energy resources in the optimization process. The deficiencies of the day-ahead technique can be overcome by using a real-time approach and by taking advantage of the real time data flow offered by the smart grid technology such as two-way communication systems. Real-time data provides the optimization process with both the state of the system at all-time and the real-time marketing information. This data is to be processed every minute (60 seconds) in an intelligent way to minimize the cost. In this work, a real-time approach is applied to design an optimal dispatcher and market place architecture for a microgrid system. An obvious benefit of such application is a smarter energy management that enables effective, reliable, and economical scheduling of the available power resources including intermittent renewables and storage systems.;The microgrid under test in this thesis includes different types of resources such as conventional distributed generators (DGs), wind turbines (WT), fuel cells (FC), photovoltaic (PV), and batteries for storage. The proposed algorithm is able to integrate both conventional and renewable energy resources simultaneously in the optimization process of the total operation cost. Real-time measurements on the availability of solar and wind power, fuel cell state, battery storage level and market price on a minute basis provide continuous flow of information to the automated optimizer/scheduler in order to choose the optimal resources.;The results of the simulation show that the proposed approach successfully and economically managed the resources available in the microgrid during 24-hour of typical load and renewable energy change constantly. Moreover, the results show that the real-time exchange of data and market prices with the main-grid allowed an active participation of the microgrid as a whole in the spot market and penetration and dispatch of renewables.