Stochastic Distributed Frequency and Load Sharing Control for Microgrids With Communication Delays

Abstract

This paper addresses the frequency restoration and accurate load power sharing problem of ac microgrids with massive penetration of distributed generators (DG) under time-delay communication in noisy environments. Existing distributed control methods commonly assume ideal communication among DGs. However, the channels are prone to additive noises and time delays, while each DG obtains noisy and delayed measurements of the states of its neighbors due to environmental noises and communication delays. The proposed distributed cooperative control strategy will achieve frequency restoration and accurate load power sharing among DGs through a sparse communication network subject to time delays and noise disturbances. The theoretical concepts and necessary conditions for stability and robust performance of the proposed distributed cooperative control strategy are outlined by the Lyapunov-Krasovskii functional method and stochastic differential equation theory. Furthermore, the proposed control strategy is implemented through sparse communication networks and thus, satisfies the plug-and-play feature of the future smart grid. Simulation results on an islanded microgrid test system are provided to reveal the effectiveness of the proposed control method to provide accurate proportional power sharing in the MATLAB/SimPowerSystems Toolbox.