Disturbance Observer Based Distributed Consensus Control Strategy of Multi-Agent System with External Disturbance in a Standalone DC Microgrid

This article proposes the secondary voltage control of microgrid on the basis of cooperative control of multi agent system. The distributed cooperative control utilizes disturbance observer technique to synchronize the DC bus voltage. The proposed controller achieves balanced power sharing among the battery energy storage units (BESUs) in the presence of external disturbances in heterogeneous microgrid (MG) network. The dynamics of heterogeneous nodes affected by constant disturbance such as error measurements, sudden load variations and communication link failure between distributed generator units make the network highly heterogeneous. Firstly, a disturbance observer is established to estimate the disturbance generated from the MG system. Secondly, distributed consensus control law is designed to suppress the disturbances acting on the multi-agent system. Furthermore, communication delays are explicitly considered in the analysis. The presented control strategy is compared with the existing mainstream algorithms to check the feasibility of the designed control method. The effectiveness of the proposed control law for isolated DC MG system has been validated by MATLAB/Simulink platform using simulation case studies.