Distributed Voltage and Frequency Control of Islanded AC Microgrids

This paper proposes a novel secondary voltage and frequency control system for islanded AC microgrids. The main properties of the proposed controller arc that: 1) It tracks the frequency and the voltage magnitude references in finite-time. 2) The control is insensitive to the communication network changes and to plug-and-play operations. 3) The control is effective regardless of the nature of the distributed generators (DGs) and the loads. 4) The distributed nature of the controller obviates the complex communication network needed for centralized control systems and the inherent communication delays, and boost the microgrid's reliability as it no longer controlled by one centralized controller. A novel distributed sliding-mode technique was developed in this paper to design the proposed control system. A case study is carried to highlight the robustness of the distributed controller regarding voltage and frequency references tracking, communication network changes and plug-and-play operations.