الفهرس 
1.3 Components of Wind Energy Conversion System
MODELING AND ANALYSIS OF A WECS INCLUDING A FULLY SUPERCONDUCTING GENERATOROnly 14 pages are availabe for public view
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Abstract
Renewable energy sources offer an alternative power supply that overcomes the disadvantages of conventional energy sources. Renewable energy sources are
environmentally clean, safe, free and available energy sources, and also able to cover the increasingly consumption of energy. Wind Energy Conversion Systems
(WECSs) are one of green energy types that have become more popular due to
environmental concern and the need to reduce greenhouse gas emission. The
doubly fed induction generator, permanent magnet generator and superconducting generator, can be employed in variable speed WECS. With recent progress in technologies of AC superconducting wires, it has become possible developing a fully superconducting generator (FSG). Significant efforts have been made to
develop FSG for usage with WECSs.
In FSG, both field and armature windings are superconducting materials. For this
reason, FSG has less weight than any other generator having the same rated
power. Meanwhile, the size of the blade and the power output of WECS would
both be increased due to the generator weight reduction. This thesis investigates a 2 MW wind turbine, driving an FSG that is connected to
the grid via a back-to-back converters system consisting of two voltage source
converters (rectifier and inverter) coupled by a DC link capacitor. The considered system is simulated in MATLAB/SIMULINK to study its performance under various disturbance and operating conditions. The system under study is equipped with proper control schemes: pitch angle control to limit the generated power within rating; generator-side controller to adjust rotor speed at the desired one to apture the maximum power from the generator and grid-side converter controller to control the power flow and keep the DC-link voltage constant. Proportional
integral (PI) controllers are utilized as conventional controllers to enhance the system stability and to improve its performance under the transient conditions; namely 3-phase short circuit fault, one-circuit outage, and step increase in wind speed. Also, Fuzzy Logic (FL) controllers are designed as a possible alternative to the PI controllers in generator and grid side converters to improve the system
performance. The parameters of each of PI controllers and FL controllers are
optimally selected using PSO technique. The simulation results with both the PI
and FL controllers are introduced in a comparative form under different operating conditions. Simulation results show that the performance of the considered FSG-based WECS is well improved using either of the designed converters’ controllers. Meanwhile, simulation results reveal that the proposed FL control scheme is more effective in enhancing the stability of the FSG-based WECS than the PI controllers.