Optimal microgrid scheduling to provide operational flexibility in main grid operation

The penetration of renewable energy sources into power systems has been increasing to mitigate the concerns for the environment, global warming, and rising fuel prices. However, the variability and uncertainty of power output from renewable energy sources raise challenging issues for power system operation, which draws attention to the need for operational flexibility. In this paper, we propose an optimal scheduling method for a microgrid that can provide the flexible ramping capability to the main grid. To investigate the effectiveness of the proposed method, a microgrid, which has an energy storage system and small-scale dispatchable generating units in order to not deploy the involuntary load shedding in an emergency condition, is postulated, and numerical simulations are carried out. We consider the energy storage system and dispatchable units as providers for flexible ramping capability and show that the proposed approach enables highly cost-effective distribution system operation. The simulation results verify that scheduling performance can be improved using the proposed method compared with the conventional scheduling method.