Improved control scheme of DFIG wind turbine systems under unbalanced grid voltage

This paper proposes an enhanced nonlinear control technique based on a combination of feedback linearization (FBL) and resonant regulator as tracking controllers for the doublyfed induction generator (DFIG) wind turbine system under unbalanced grid voltage. A nonlinear model of DFIG wind turbine system with the rotor-side converter (RSC) is firstly linearized, not by small signal analysis.