Two-Stage Robust Operation of Battery Energy Storage and Direct Load Control in A Microgrid

Battery energy storage systems (BESSs) in microgrids can efficiently store surplus renewable energy and release it during peak-load periods, achieving an energy time shifting function. However, the renewable power generation such as wind and photovoltaic (PV) is uncertainly varying. To this end, direct load control (DLC) can be applied to dynamically control load consumption to track the varying renewable power generation, keeping microgrid operating constraints. Considering advantages of the BESSs and the DLC, this paper proposes a two-stage coordination framework. In the first stage, the BESS charging and discharging are scheduled one day ahead to shift energy over a day. Then, in the second stage, the DLC is implemented in short operation periods to track uncertainty realization to keep the operating constraints. To robustly coordinate these two stages under uncertainties, a two-stage robust optimization method is utilized to solve the operation optimization problem. By doing so, the operating cost can be minimized and the microgrid operating constraints can be guaranteed under the uncertainties, achieving a two-stage robust operation method of the BESS scheduling and the DLC. Simulation results verify high solution robustness of the proposed two-stage robust operation method against uncertainty realization.