Design and Simulation of a Novel Subsynchronous Control Interaction Damping Controller

Sub-synchronous control interaction (SSCI) is an interaction between a power electronic control system and a series-compensated electrical network. This issue has gained attention due to the recent SSCI phenomena reported in doubly fed induction generator (DFIG)-based wind farms connected to series-compensated lines. To suppress SSCI, this paper proposes the design and implementation of a novel control strategy for optimizing the robust characteristics of converter controller using the active disturbance rejection control (ADRC). In this control framework, the extended state observer is designed for state observation and disturbance estimation. Then, a nonlinear state-error feedback function is constructed to further improve the tracking performance of the system. Simulations and experimental results show that the ADRC performance is better than the traditional proportional integral (PI) controller. The ADRC is able to properly damp the SSCI of DFIG wind turbines by improving the robustness without the need of expensive additional damping devices.