Nonlinear Subsynchronous Oscillation Damping Controller for Direct-Drive Wind Farms With VSC-HVDC Systems

Due to the subsynchronous interaction between grid-side converter (GSC) of wind farms and rectifier (REC) voltage source converter-based high-voltage direct current (VSC-HVDC) transmission system, oscillations (SSOs) may occur in direct-drive with VSC-HVDC systems. Considering nonlinearities uncertainties a nonlinear SSO mitigation strategy is proposed this article based on feedback linearization theory sliding mode control (SMC). The used eliminate nonlinearities, SMC adopted improve robustness against disturbances. (FLSMC) takes advantages (FLC) SMC. FLC transforms forms GSC REC into linear through coordinate transformation feedback. that sensitive parameter external disturbances, combined system robustness. An eigenvalue analysis time-domain simulations are carried out, which demonstrates outperforms over traditional proportional–integral for decoupling. Meanwhile, FLSMC shows better disturbances damping control.