  The Direct Torque Control (DTC) is well known as an effective control
technique for high performance drives in a wide variety of industrial
applications and conventional DTC technique uses two constant reference value:
torque and stator flux. In this paper, fuzzy logic based stator flux
optimization technique for DTC drives that has been proposed. The proposed
fuzzy logic based stator flux optimizer self-regulates the stator flux
reference using induction motor load situation without need of any motor
parameters. Simulation studies have been carried out with Matlab/Simulink to
compare the proposed system behaviors at vary load conditions. Simulation
results show that the performance of the proposed DTC technique has been
improved and especially at low-load conditions torque ripple are greatly
reduced with respect to the conventional DTC.
