Distributed Secondary Control for AC Microgrids With Dynamic Performance Enhancement

In this paper, a novel distributed secondary control strategy for microgrids (MGs) has been developed, which focuses on both the steady-state and dynamic performance of the system. The proposed controller achieves accurate secondary frequency and voltage regulation in the steady state, along with proportional active and reactive power sharing among distributed generators (DGs). Additionally, it actively suppresses the overshoots and ensures enhanced dynamic performance when the system is disturbed. Compared to the conventional methods, the proposed control does not require precise knowledge of the system parameters and could be applied to a wide range of grid topologies without additional communication need. The Lyapunov stability of the controller has been proved, and its performance has been extensively analyzed in both steady and dynamic states. A Controller-Hardware-In-the-Loop (C-HIL) testbed has been developed, and the effectiveness of the proposed control strategy has been validated on an islanded MG with four DGs.