Distributed Optimal Coordination of Microgrid Systems over Unbalanced Digraph

Abstract

This paper is concerned with the distributed optimal coordination problems of microgrid systems over unbalanced digraph where the microgrid systems aim to schedule the active power outputs of the systems to meet the generation-load balance and minimize the total operating cost. However, the communication topology with an unbalanced digraph causes the imbalance of information transmission among agents. This impedes the optimal coordination for microgrid systems. To overcome this problem, by estimating the left eigenvector of the graph Laplacian matrix, a novel integrated distributed control strategy is proposed, which consists of the distributed optimal reference generator and the tracking controller. By applying this control strategy to the microgrid system, the active power outputs of the systems exponentially converge to the optimal solution of the economic dispatch problem. Finally, the effectiveness of the designed control strategy is verified by a simulation example.