A Coordinated Voltage and Frequency Control of Inverter Based Distributed Generation and Distributed Energy Storage System for Autonomous Microgrids

Distributed generation and distributed energy storage systems can be controlled to improve power system stability. This article proposes control strategies for adopting distributed generation units to autonomous microgrids. The proposed distributed generation interface is utilized not only to control the active power flow, but also to provide essential ancillary services, such as voltage regulation and frequency control, to the autonomous microgrid. A coordinated voltage and frequency control of the inverter-based distributed generation and distributed energy storage system is presented. Moreover, a frequency estimation algorithm based on orthogonal filters is adopted for the frequency control loop. One advantage of the proposed control system is its unified structure for the different operating modes. Extensive simulations of the proposed coordinated control of the inverter-based distributed generation and distributed energy storage system are conducted to evaluate the dynamic performance of the proposed microgrid.