A Review of Coupling and Interaction Studies of Grid-Forming Converters Based on Transient Stability

Grid-forming (GFM) inverters, with their synchronous voltage source characteristics, have attracted widespread attention in recent years due to their ability to effectively enhance the stability of power-electronic-based new power systems. The document starts by examining the mechanism of system stability established by GFM and analyzes the issues that need to be addressed urgently after GFM is integrated into the system. Grid-forming control establishes multiple coupling channels with the grid connection point to provide voltage and frequency support. However, the frequency coupling also brings about many interaction issues. The document divides the coupling interaction issues into "internal coupling" and "external interaction" issues based on whether the control structure modification is considered, and evaluates the research path for them.