Coordinated control strategy for grid connected DFIG wind system under voltage imbalance

The operational characteristic of doubly fed induction generator under voltage imbalance condition is analysed in this paper. A co-ordinated control strategy employing generator side and grid side converters is presented in this paper. The control strategy calculates the compensation unbalanced voltage which is then incorporated with the reference voltage of generator side and grid side converter in order to restrain the electro magnetic torque pulsation effectively. To validate the effectiveness of the proposed control strategy, the topology is implemented in MATLAB/Simulink for 1.5 kW DFIG grid connected system which is subjected to voltage unbalance. The results obtained shows that the proposed control technique can effectively reduce the torque pulsation and stator reactive power.