Modeling and Stability Analysis of Inverter-based Networked Microgrids

Inverter-based power systems rely heavily on grid-following (GFL) inverters for renewable energy integration, with both GFL and grid-forming (GFM) inverters playing critical roles, especially in islanded mode. This paper analyzes the operational stability of a network of microgrids (MGs) in a 100% inverter-based system undergoing topology reconfiguration via switching. A nonlinear state-space model is developed, incorporating coordinated inverter controls and communication delays. System stability is assessed using a domain of attraction (DoA)-based evaluation scheme, validated through time-domain simulations in MATLAB/Simulink. The scheme further quantifies the impact of GFL grid-support functions and communication delays on large-signal stability.