Distributed cooperative control strategy for islanded microgrids

Abstract

In this paper, a distributed cooperative control strategy for islanded microgrids (MGs) is proposed, to minimize the total generation cost of distributed generators (DGs), and maintain the state of charge (SoC) balancing of battery energy storage systems (BESSs). First, a consensus-based economic dispatch (ED) strategy is proposed, to achieve the minimum total generation cost of DGs, while the aggregated power output of DGs meets the power dispatch command from the supervisory control system. Further, an SoC-based droop control strategy is developed for BESSs, to maintain the SoC balancing and power balance in the islanded MG simultaneously. Compared with the centralized control schemes, the proposed cooperative control strategy is fully distributed such that it simply requires local information exchange without the necessity of a central controller. More importantly, the proposed cooperative control strategy is able to achieve multiple control objectives in a unified framework. Finally, the simulation results in an islanded MG with renewable energy and time-varying load demands are presented, to demonstrate the effectiveness of the proposed distributed cooperative control strategy.