الفهرس 
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Abstract
Over the past few years, it is a general trend to cut the world’s CO2 emissions in half by 2050. However, electricity demand- a major source of CO2 emissions will double by that date. Of various alternative energy sources, wind energy is one of the most prominent source of renewable energy sources today. The increasing concerns to environmental issues demand the search for more sustainable electrical sources. Wind turbines are possible solution for the environmental friendly energy production as it is said to hit large integration in the near future. The challenge is to achieve system functionality without extensive custom engineering, yet still have high system reliability and generation placement flexibility. Now days, it is a general trend to increase the electricity production using wind energy distributed generation (WEDG) systems. If these systems are not properly controlled, their connection to the utility network can generate problems on the grid side. Therefore, considerations about some technical barriers such as, power generation, safe running and grid synchronization must be done before connecting these systems to the utility network. WEDG systems have to overcome these technical barriers if it should produce a substantial part of the electricity. In the wind energy based power system the objective of the control strategy is to generate and deliver power as economically and reliable as possible while maintaining the voltage and frequency within permissible limits. The WEDG systems are conventionally equipped with both conventional blade pitch controllers (CBPCs) and automatic voltage regulators (AVRs) to improve the system performance. Unfortunately, CBPCs and AVRs may affect stability. Exposed to disturbances, such as wind variations, operating point variations and short circuits, power systems may exhibit unacceptable swing mode oscillations or loose synchronism. To damp and suppress these oscillations blade pitch controllers and Power system stabilizers (PSS) are normally incorporated. Design and application of classical BPC (CBPC) and conventional PSS (CPSS) has been the subject of continuing development for many years. The usual design approach is based on linearized system model with fixed system parameters. Blade pitch controllers and Conventional power system stabilizers are based on linearized machine model and thus tuned at a certain operating point. However, WEDG systems are highly non linear systems. CBPC and CPSS tuned at a certain operating point may not work properly for the actual plants. If the system drifts from the original operating point, the performance of controllers degrades significantly. Alternative control techniques including self-tuning regulators, pole placement, robust control, and pole shifting have been investigated for the design of blade pitch controllers and power system stabilizers. This involves obtaining a frequency response of the systems. There is a problem associated with it when noise is present. To achieve the desired objective, a design of AI-Based Controllers for the wind energy distributed generation based interconnected power system will be proposed in this research work. In recent years, PID control system and fuzzy-logic control have been proposed for power system stabilization problems. Fuzzy logic controllers are nonlinear controllers based on the use of expert knowledge. This knowledge is usually obtained by performing extensive mathematical modeling, analysis, and development of control algorithms for power systems. In this research four controllers with different control techniques are used to stabilize wind energy distributed generation systems. The first controller developed in this research is blade pitch PID controller optimized using particle swarm optimization technique (PSO). Simulation results significantly clarify the effectiveness of the proposed PSO based blade pitch PID controller and its flexibility towards improving the system’s dynamic behavior and enhancing the system’s stability under parameter uncertainties. The second controller is fuzzy-logic power system stabilizer (FLPSS). The controller uses the speed deviation and the deviation in accelerating power of the synchronous machine as the inputs. The reliability of the proposed controller is proved through a comparison of its response to those both of CPSS and another FLPSS with larger rule size. The third controller is variable-structure adaptive fuzzy-logic power system stabilizer (AFPSS). The effectiveness of the proposed controller is investigated through a comparison of its response to those both of CPSS and the second proposed controller. The fourth controller is predictive fuzzy-logic power system stabilizer (PFPSS). To investigate the PFPSS performance, its response is compared to CPSS, FLPSS, and AFPSS. The design procedures for the proposed controllers are used to propose new strategies for the stabilization of the wind energy distributed generation based interconnected power system. Case studies are carried out to evaluate the effect of the proposed controllers on the behaviour of the system. The proposed controllers are added one at a time to the model. The obtained results prove better system performance with the added controllers. Finally, the experimental work for implementing the proposed controllers applied to the wind energy distributed generation based interconnected power system were carried out using hardware in the loop technique (HIL). The obtained results using digital signal processor (DSP) proved that the controllers exhibit an excellent performance.