Small-Signal Modeling and Stability Analysis of Delay-Dependent Cyber-Physical Microgrid System Under Hybrid Secondary Control

This paper studies stability issues in islanded delay-dependent cyber-physical microgrid systems (CPMGSs) with the distributed hierarchical control framework. Firstly, a distributed consensus algorithm and decentralized point of common coupling voltage estimation-based hybrid secondary control is proposed for the distinctive capability of PCC voltage restoration, as well as power sharing and frequency restoration. Besides a novel linearized small-signal modeling method is developed for the frequency-domain stability analysis with low computational complexity, based on which the time-delayed state-space model (SSM) of the CPMGS is derived. Lastly, the time-domain simulations carried out in Matlab and systematical eigenvalue analysis in frequency-domain stability verify the effectiveness of the proposed control method and the accuracy of the SSM.