Modeling and Stability Analysis for Networked Hierarchical Control of Islanded Microgrid

The microgrids (MGs) are key elements for integrating distributed energy resources as well as distributed energy-storage systems. In this paper, a network-based hierarchical control scheme is proposed for the enhancement of frequency, voltage quality in MGs. The primary control includes the droop method and the virtual impedance loops, in order to share active and reactive power. The secondary control restores the frequency and amplitude deviations produced by the primary control. And the tertiary control regulates the power flow between the grid and the Microgrid. Also, a distributed networked control system is used in order to implement a distributed secondary control (DSC) thus avoiding the use of a microGrid central control (MGCC). The frequency and voltage of the MGs not only ensures reactive proposed approach, but also able to restore power sharing. The modeling and stability analyses of the hierarchical control system are derived. Real-time simulation results from hierarchical-controlled MGs are provided to show the feasibility of the proposed approach.