Direct Torque Control of Three Phase Induction Motor Using Fuzzy Logic Rajendra

Induction motor drives using field oriented control (FOC) for torque and flux control have been used in high performance industrial applications instead of dc motors for many years. In FOC, torque and flux of an induction motor can be controlled independently by decoupling the stator current into its orthogonal components. The FOC method has achieved a quick torque response. But in order to achieve expected performance from FOC, exact identification of parameters is required. A new torque and flux control scheme called the direct torque control (DTC) has been introduced for induction motors. In DTC the torque and flux of an induction motor can be controlled directly by applying a suitable voltage vector to the stator of an induction motor. However, convectional DTC result in large torque and flux ripples. In this paper, a controller based on fuzzy logic is designed to improve the performance of DTC and reduce the torque and flux ripple.