Distributed Secondary Voltage Control of Microgrids with Nonuniform Time-Varying Delays

In this paper, we propose a distributed secondary voltage control for microgrids. First, the communication network of the distributed generators (DGs) in a microgrid is modeled by a fixed directed graph with nonuniform time-varying delays. Next, the nonlinear dynamics of the DGs is transformed to a second-order linear system through an input-output linearization technique. A distributed controller is proposed for each generator to ensure its voltage magnitude to converge to a reference voltage. Moreover, the stability of the closed-loop system is analyzed with a Lyapunov-Razumikhin function method. Finally, some simulation results are given to verify our results.