Impacts of Grid Structure on PLL-Synchronization Stability of Converter-Integrated Power Systems

Small-signal instability of grid-connected power converters may arise when the use phase-locked loops (PLLs) to synchronize with a weak grid, i.e., operating in grid-following mode. Commonly, this stability problem (referred as PLL-synchronization paper) was studied by employing single-converter system connected an infinite bus, which, however, omits impacts grid structure and interactions among multiple converters. Motivated this, we investigate how affects multi-converter systems. Moreover, provide guidelines on improve systems PLL-retuning, proper placement converters, or enhancing some connections network. Finally, validate our findings simulation results based 39-bus test system.