Optimal Operation of Energy Storage System in a Hybrid Microgrid Considering Load Uncertainty

In this paper, the optimal operation of the energy storage system in a hybrid microgrid with respect to load uncertainty is examined. An energy storage system such as a battery or other energy storage technologies used in hybrid microgrids with multiple distributed generations (DGs) is considered. Optimal utilization of the storage system is to select the optimum location, determine the optimum capacity and optimal charging and discharging planning. The optimal operation of the storage system used in the hybrid microgrid is challenging due to uncertainties in various system parameters. The optimization problem in this paper is a nonlinear and non-convex problem, therefore ordinary problem solving methods such as linear programming are inapplicable. On the other hand, uncertainty of load, weather conditions and energy storage system can have a significant impact on the problem of optimal operation of the storage system. Moreover, a new optimization algorithm named stochastic quasi-gradient method (SQGM) is utilized in order to optimize the nonlinear and non-convex objective function under load uncertainty. Simulation results on a typical hybrid microgrid confirm the effectiveness of the proposed algorithm.