الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
In recent years, many studies have been carried out to develop solutions for the induction motor control, in order to achieve precise and quick torque response. The direct torque control (DTC) technique has been recognized as viable solution to achieve these requirements. It requires less sensors and does not depend heavily on motor parameters variation.
This thesis presents the implementation of direct torque control (DTC) of a 3-phase induction motor, and illustrates the features of this control technique. A model of the induction motor, inverter and DTC hysteresis controllers is constructed for digital simulation,
A complete comparison for drive performance, with and without initial stator flux, is performed using Matlab-Simulink package. The effect of parameter variation on the system performance is also studied.
One of the drawbacks of the conventional DTC is the relatively large torque npplt esKcially in the low speed region The variation of the switching frequency according to the amplitude of torque, flux hysteresis band and the motor speed is another drawback. A comprehensive comparison of two high performance ripple reduction algorithms of direct torque control (DTC) of an induction motor is presented. One method uses a torque slope calculation controller, the other uses a duty-cycle controller. To verify the feasibility of the two schemes, numerical simulation and comparison with conventional DTC are carried out.