Distributed CPS-Based Secondary Control of Microgrids With Optimal Power Allocation and Limited Communication

In this paper, we investigate distributed secondary control of the inverter-based microgrid with its distributed generations (DGs) being interconnected through limited communication, namely, only quantized data can be transmitted among each pair of DGs at some time instants according to the event-triggered mechanism. We employ a framework of cyber-physical system (CPS) for newly developing the distributed control algorithms, which generate the distributed secondary control signals at the control layer as well as achieve the frequency and voltage restoration, and the optimal allocation of active power concurrently for all DGs at the physical layer. Also, the presented algorithms have the capability of excluding the Zeno behavior. The optimization action merely requires one controller designed for the derivative of active power to fulfill, no redundant control. Additionally, the presented algorithms are extended to the application with time-varying heterogeneous communication delays on the original basis, in which the negative effect of delays is well compensated by applying the Artstein model reduction method. Besides, the sufficient criteria on the control parameters for obtaining the aforementioned control and optimization goal are rigidly derived with the aid of the tools of nonsmooth analysis, Gronwall's inequality, and Lyapunov stability. Finally, several case studies and their results are presented to verify the effectiveness and superiority of the presented algorithms.