Improved Direct Torque Control of a Doubly Fed Induction Generator in a Wind Energy Conversion System

This paper proposes a control strategy of a wind turbine system driving a doubly fed induction generator (DFIG). This strategy is based on a twelve sectors direct torque control (DTC). Rotor flux and electromagnetic torque are controlled by hysteresis controllers and rotor voltage is determined using a switching table. In addition, the maximum power point tracking (MPPT) control strategy is also proposed to extract the maximum power from the wind turbine generator whatever the wind speed is. Simulation results, in the MATLAB/SIMULINK environment, show the performance and efficiency of the twelve sectors direct toque control (DTC).