Intelligent Controller for Energy Storage System in Grid-Connected Microgrid

This paper presents the design of a fuzzy logic-based controller to be embedded in a grid-connected microgrid with renewable and energy storage capability. The objectives of the controller is to control the charge and discharge rate of the energy storage system (ESS) to reduce the end-user operating cost through arbitrage operation of the ESS and reducing the power exchange between the main and microgrid. Instead of using a forecasting-based approach, the proposed methodology takes the difference between the available renewable generation and load, state-of-charge of ESS, and electricity market price to determine the charge and discharge rate of the ESS in a rolling horizon. A comparison with other controllers with similar objectives shows that the proposed controller can achieve a lower operating cost and reduce the power exchange between the main and microgrid.