الفهرس 
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Abstract
Wind-speed estimation, wind turbine modeling and wind turbine control are investigated in this thesis.A real case study has been adopted to forecast the wind-speed blowing on Egypt’s north-western coast. Three effective time series stochastic wind models for Egypt’s north-western coast are proposed and optimized using ANFIS and Kalman Filter (KF).
A study of the power and torque coefficients, as well as, the turbine output power and output torque profiles in 2D and 3D (change in pitch angle of the turbine blades could be an added dimension; visualized as multiple consequent surfaces) have been presented.
Fuzzy logic systems have been investigated and new interval type-2 fuzzy logic control schemes for control grid side converter (GSC) is developed. Robust and good results are achieved considering uncertainty and nonlinearity of wind speed. Finally, results for doubly-fed induction generator DFIG active and reactive powers control using DTC-PWM controller are proposed and simulated.
Direct Torque Control is a control technique used in AC drive systems to obtain high performance torque control. The conventional DTC drive contains a pair of hysteresis comparators, a flux and torque estimator and a voltage vector selection table. The torque and flux are controlled simultaneously by applying suitable voltage vectors, and by limiting these quantities within their hysteresis bands, de-coupled control of torque and flux can be achieved. However, as with other hysteresis-bases systems, DTC drives utilizing hysteresis comparators suffer from high torque ripple and variable switching frequency. The most common solution to this problem is to use the space vector depends on the reference torque and flux. The reference voltage vector is then realized using a voltage vector modulator. DTC-PWM has been proposed and applied to the Rotor side converter of DFIG. The simulations were carried out using MATLAB/SIMULINK simulation package.