The paper presents the complete modeling and control strategy of variable speed wind turbine system (WTS) driven brushless doubly fed induction generators (BDFIG). A back-to-back converter is employed for the power conversion exchanged between BDFIG and grid. The wind turbine is operated on the maximum power point tracking (MPPT) mode its maximum efficiency. Direct power control (DPC) based on selecting of the appropriate CW stator voltage vectors and the errors of the active and reactive power, the control strategy of CW stator side converter (MSC) combines the technique of MPPT and direct power control. In the control system of the grid side converter (GSC) the direct power control based an improved switching table (IST-DPC) with notch filter has been used to maintain a constant DC-Link voltage and the reactive power is set to zero and better current quality compared with the conventional switching table .in addition, the behaviors of BDFIG under unbalanced grid voltage conditions are studied and a power compensation scheme is developed to improve the power quality. Simulations results using MATLAB/SIMULINK are presented and discussed on a 7.5 KW BDFIG wind generation system demonstrate the effectiveness of the proposed control.

Full text: IJEIR_2307_FINAL.pdf