Hybrid Interval-Robust Adaptive Battery Energy Storage System Dispatch with SoC Interval Management for Unbalanced Microgrids

Battery energy storage systems (BESSs) have been widely deployed in microgrids to deal with uncertain output power of renewable distributed generation (DG) and improve renewable energy utilization efficiency. However, due to the short-term dispatch mode and BESS capacity limitation, current BESS dispatch decisions may not be efficient from a whole-day perspective, leading to an inadequate/excessive state of charge (SoC) for subsequent dispatch. To address this issue, an adaptive BESS dispatch method with SoC interval management is proposed for unbalanced three-phase microgrids, aiming to minimize the operating cost. In a day-ahead stage, an SoC interval is optimized considering the uncertainties of renewable DG, loads and market prices. During the day, the BESS is dispatched inside the SoC interval with a rolling horizon procedure to track uncertainty realization. Accordingly, a hybrid interval-robust optimization method is developed to solve the proposed scheduling problem under the uncertainties and procure the optimal SoC interval. Particularly, a decomposing and alternating solution algorithm is developed to identify the pessimistic case based on robust optimization while the SoC interval is determined on the basis of interval optimization. Simulation results verify high efficiency and solution robustness of the proposed hybrid interval-robust adaptive BESS scheduling method. © 2010-2012 IEEE.