Impacts of Operating Points on the Stability of Microgrids Consisting of Gird Forming Inverters

Grid-forming inverters (GFMIs) have been more popular because of its ability to control both the voltage and frequency in better way than grid-following inverters. This capability is critical in future grids with high renewable resources penetration, as it ensures reliable operation, prevents blackouts, and supports the transition to a cleaner energy future. However, with the change of generation level of inverters, the operating points of the system may also change, whose impacts on the stability of grids with GFMIs are still not clearly understood. To fill the gap, a single-GFMI-infinite-bus system and a multi GFMI microgrid system with different operating points are investigated in this paper. The eigenvalue analysis for both system is conducted. Time-domain simulations are also performed.