To analyze the impact of direct-drive wind turbine integration on power system small-signal stability while avoiding complex modeling

this study combines modal energy analysis technology with the eigenvalue method from classical small-signal stability theory

establishing a modal damping energy function for evaluating system dynamic behavior. The low-frequency dynamic phenomena caused by grid integration of direct-drive wind turbines are quantitatively characterized in an energy terms. Firstly

the distribution characteristics of low-frequency oscillation modal damping energy in systems with multiple direct-drive wind turbines integrated into the grid are analytically examined. Subsequently

the modal damping energy of key oscillation links is extracted. Based on modal energy analysis and eigenvalue sensitivity theory

a quantitative stability evaluation framework suitable for direct-drive wind turbine grid-connected systems is established

and the effects of different integration locations of direct-drive wind turbines on power system dynamic oscillation characteristics are investigated. Finally

a small-signal stability regulation strategy for direct-drive wind turbine integration is proposed based on small-signal stability evaluation indices and sensitivity indicators. The reliability and applicability of the proposed method are validated through small-signal stability analysis in both a 3-machine 9-bus system and the New England 10-machine 39-bus system.