A Comparative Large-Signal Stability Analysis of Grid-Following and Grid-Forming Converter

This paper presents a comparative large-signal stability analysis of grid-following (GFL) and grid-forming (GFM) converters under significant grid disturbances. A comprehensive framework is established using geometric method, Lyapunov method, and time-domain simulations to evaluate various synchronization mechanisms, including voltage-based, power-based, and virtual-oscillator-based approaches. The results indicate that the Lyapunov method yields a more conservative basin of attraction (BOA), particularly for GFL converters, due to their distinct damping behavior compared to GFM counterparts. Moreover, a time-limited reverse integration method is developed to meet grid code requirements on current recovery time, while enabling sensitivity analysis across a wide parameter range for robust converter design.