الفهرس 
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Abstract
Direct Torque, and Flux Control (DTFC) of Switched Reluctance Motor (SRM) fed by a voltage source inverter is the simplest control strategy that does not need long computation time, can be implemented without mechanical speed sensors and is not sensitive to motor parameter variations which means parameter identification process is not needed. In principle, the motor terminal voltages and currents are sampled and used to estimate the motor flux linkage and electromagnetic torque. By virtue of observing the flux linkage vector position and the instantaneous errors in stator flux linkage, and torque magnitudes, a space voltage vector is selected to restrict the torque and the flux errors within their respective flux, and torque hysteresis bands. In this thesis a Fuzzy Logic (FL) speed controller is presented for adjustable speed DTFC based SRMs driven using voltage source inverter. Simulation results confirm the superiority of the presented controller in fast speed tracking capability over wide speed control range without affecting system stability. The speed control of SRMD by means of the Artificial Intelligence (AI) based FL technique using Space Voltage Pulse Width Modulation (SVPWM) concept has been investigated in this thesis. According to reference speed trajectory the FL controller has shown good performance. The settling time of the torque, and speed matched with the desired values that were taken during the simulations. XX By the method presented in this thesis, the efficiency, performance, robustness, and reliability of SRMD increases. There is no steady state error in speed control is acceptable and there is no any overshoot. In the research the conventional DTFC, the selected space voltage vector is applied for the whole switching period regardless of the magnitude of the torque error. Moreover, high torque ripples due to the selected space voltage vector DTFC always generate the optimum stator space voltage vector not the exact one required to obtain the desired electromagnetic torque and stator flux linkage. In conventional DTFC, the proportional plus integral (PI) controller when used as a speed controller needs its parameters to be retuned every time the speed set point is changed because the SRM is highly nonlinear behavior. Experimental work presents building of SRM beginning from stator and rotor laminations cutting and preparation using laser cutting machine then assembled by hydraulic compressor with suitable shaft, finally front, and back end cover assembly. Measuring and evaluating flux linkage, and inductance characteristics. That makes SRM ready to control and operate as a part of switched reluctance motor speed drive SRMD.