Improving stability for independent power control of wind-turbine Doubly Fed Induction Generator with SFOC and DPC during grid unbalance

This paper presents modified SFOC of Doubly Fed Induction Generator (DFIG) in wind turbines during grid unbalance for improved stability by using Notch filter to eliminate second order harmonic components. Comparison of the proposed controller with DPC using Notch filters for improvement during grid voltage unbalance is also included. The system consists of an induction generator with slip ring and power electronic converters at both rotor and grid sides. The modifications are applied to rotor side converter for active and reactive power controls of wind turbine. The turbine, generator and control units are also described. The investigation is based on MATLAB/SIMULINK. Simulation results show improved stability of active and reactive powers delivered by DFIG.