Small-Signal State-Space Model for Analyzing Interactions of Voltage Source Converters in AC Networks

This paper presents an approach to overcome limitations in existing small-signal state-space models for grid-connected voltage source converters (VSCs). While prior models effectively analyze single converters in grid-following control mode, they fall short in capturing the dynamic interactions among multiple converters operating in different dq frames. Thus, this paper introduces a generalized small-signal state-space model for VSCs used as wind turbines’ grid-side converters (WT-GSCs). This model addresses dynamic interactions influenced by phase-locked loops (PLLs). The proposed methodology eliminates the need to linearize complex equations and demonstrates potential applicability in various VSC configurations beyond the specific focus on wind turbine converters.