الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present thesis investigated novel schemes for speed control of the three-phase induction motor. The scheme is based on switching the neutral point of motor stator windings. By using that scheme, the AC supply of a constant voltage magnitude and frequency is modulated in both frequency and effective voltage magnitude. Controlling the speed of three-phase induction motors by modulating the AC supply frequency and voltage using the stator neutral point switching is studied. Morever, an integral-cycle voltage control strategy for three-phase induction motors can be implemented via stator neutral point switching converter. The motor speed can be controlled based on the integral-cycle voltage control as discussed above. Also the thesis designed two additional controllers based on Artifical Intelligent techniques namely the Fuzzy Logic speed cvontroller and Artificial Neural network based time sliced feedback controller.
The closed loop speed control system of integral-cycle voltage modulation of the free-phase induction motor using the Fuzzy Logic cvontroller (FLC) and the stator neutral point switching is investigated. The Artificial Neural Network (Ann) controller for closede loop speed control system of integral-cycle voltage controlled three-phase induction motor is also designed and the motor speed response is evaluated.
The conventional Pulse Width Modulated (PWM) inverter is used for supplying AC power to the three-phase induction motor. The Fuzzy logic controller for closed loop speed control system of a PWM inverter-fed three-phase induction motor is evaluated. The motor speed response is compared with the conventional PWM. Also the Artifical Neural Network (ANN) controller for the closed loop speed control system of PWM inverter-fed three-phase induction motor is designed. The motor speed dynamic response is validated in comparison with the conventional PI control scheme. Moreover, The hybrid Neuro-Fuzzy controller for closed loop speed control system of the three-phase induction motor is developed and validated. All the above speed control techniques have been designed, prototyped analyzed and the results have been obtained by digital simulationb and validated by experimental testing and prototyping.