Dynamic Characteristic Comparisons between Single-Phase and Three-Phase Grid-Forming Converters

The power calculation method based on second-order general integrators (SOGIs) is generally used in single-phase grid-forming (GFM) converters, and is more complex than that of three-phase GFM converters. This distinction might lead to different dynamic characteristics between single-phase and three-phase GFM converters. To address this gap, we establish the state-space models of GFM converters with and without a dedicated damping method based on closed-loop pole allocation. Through analysis of pole distribution, the differences between single-phase and three-phase GFM converters are revealed. Finally, the analytical results are validated by comparing a cluster of 30 sets of 3-kVA single-phase GFM converters and a cluster of 10 sets of 9-kVA three-phase GFM converters in different scenarios using MATLAB/Simulink.