Small-Signal Stability Analysis of Islanded Microgrid with Grid-Forming and Grid-Following Inverter-Based Resources

Given the potential environmental impact of conventional fossil fuels and the advances in grid-interactive power electronics, microgrids with inverter-based resources (IBRs) are increasingly important in modern power grids. It is crucial to develop an understanding of the fundamental dynamic stability characteristics of a 100% IBRs microgrid. To achieve this goal, a generic small-signal microgrid model with detailed control schemes for both Grid-Forming (GFM) and Grid-Following (GFL) IBRs has been developed. Using eigenvalue analysis techniques, the key oscillation modes affecting microgrid stability have been determined. Additionally, the participation factor method was employed to examine the influence of the crucial control parameters. The results can offer theoretical support for capacity planning, parameter design, and controller optimization of the two types of inverters within a microgrid. The ultimate objective is to enhance small disturbance synchronization stability in the microgrid system.