Harmonic elimination of quasi-sine rotor injected DFIG-based wind power generation systems connected to electric power networks

• Novel harmonic elimination scheme for a group of wind power generation systems.
• Exact harmonic analysis of rotor injected DFIG-based wind power generation systems.
• Presenting a novel control scheme implemented in the rotor (αrβr)(αrβr) reference frame.

In this study, a novel control scheme including a proportional–integral–harmonic resonant (PI–R) controller is presented to eliminate the produced harmonics resulting from the quasi-sine rotor voltage injection in a doubly fed induction generator (DFIG) connected to power electric networks. The control scheme is implemented in the rotor reference frame (αrβr)(αrβr) under quasi-sine rotor injection by performing the well-known six-step switching technique. The contribution of this study is to propose a control scheme that not only keeps a grid-connected DFIG in an acceptable operating margin but also effectively eliminates the harmonic and pulsation components both in the stator and the rotor circuits caused by quasi-sine rotor injection. To validate theoretical results, a DFIG practically used to implement the available wind power plants is simulated using MATLAB/Simulink. The simulated results not only validate the theoretical results but also explicitly verify the excellent performance of the proposed control scheme.