Subsynchronous Control Interaction Analysis and Trigger-based Damping Control for Doubly Fed Induction Generator-based Wind Turbines

Doubly fed induction generator-based wind turbines are vulnerable to subsynchronous oscillations. Subsynchronous control interaction is a recently emerging subsynchronous oscillation phenomenon, which means the interaction between the rotor-side converter of a doubly fed induction generator-based wind turbine and a fixed series-compensated transmission line. In this article, subsynchronous control interaction is quantitatively analyzed, and an subsynchronous control interaction-triggered condition is created to detect the existence of subsynchronous control interaction. The subsynchronous control interaction-triggered condition is then combined with impedance scanning to effectively identify the induction generator effect and subsynchronous control interaction. Further, a subsynchronous control interaction-triggered damping control strategy is developed to effectively alleviate subsynchronous control interaction. The mitigation ability and the robustness of the presented control strategy are, respectively, verified by time-domain simulation.