Distributed Adaptive Control Scheme for Islanded AC Microgrids With Tolerance to Uncertain Communication Links

This article proposes a fully distributed resilient control scheme for islanded alternating current microgrids to achieve economic operation under uncertain communication links. Based on the well-known hierarchical control structure and consensus algorithm, a distributed resilient economic dispatch algorithm is first designed to determine the optimal generation point, and then, a distributed resilient secondary controller is developed to track the optimal generation point and eliminate the frequency deviation. Different from the robust secondary control schemes, which require the upper bound of uncertainties in dealing with the uncertain communication links and offline design the communication coupling weights through a central controller, the proposed scheme applies adaptive control technology to online design the communication coupling weights based on communication neighbor information, such that the adverse effects of uncertain communication links can be counteracted. Thus, the proposed adaptive scheme is fully distributed in contrast to existing robust schemes. The Lyapunov approach-based theoretical analysis shows that frequency restoration and generation cost minimization can be achieved for the islanded microgrid under some proper assumptions. Finally, the effectiveness of the proposed scheme is verified by several simulation studies in MATLAB/Simulink.