الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
This study explores the recent grid code polices that recommend regulations for the penetrated wind farms operation in the power system. This is conducted with concentration on the requirements regarding the faulty cases. The DFIG based wind turbines, as the most dominant distinctive configuration, is the topology under study. This is due to the DFIG control capability through its partial scale converters. Staying connected to the grid and riding through the fault is now required by all grid codes. Several DFIG protection schemes are employed for satisfying this regulation. The crowbar conventional practical method is investigated. As a way for depending on the existing resources, the DFIG converters, the role of modifying the control during the fault for improving the FRT capability is investigated. Therefore, the wind turbine generator immunity could be increased to be capable of supporting the grid through the fault without extra complex arrangements. The theoretical verification of the presented work is accomplished by Matlab program. An experimental setup is built with the facilitated equipments in the laboratory including the 3 kW wound rotor induction machine, 4 kW induction motor as a prime mover and a suitable converter/inverter units. Two DSPACE boards, DSPACE 1104 and DSPACE 1003, are used for driving the rotor side converter (RSC) and the grid side converter (GSC); respectively. Experimental doubly fed induction generator start-up procedure is introduced. Regarding the implied vector control, orientation implementing strategy is proposed. It supports stable control behavior under voltage frequency change if the control is based on voltage orientation. With its simplicity, it also facilitates the control implementation through the experimental work. Finally, the introduced FRT approach, with just control modification, is investigated on a large grid integrated wind farm where the Egyptian Zaafarana wind farm is the selected system. The thesis contains 5 chapters. The chapters are presented as following: Chapter 1 presents an introduction. The advantages of the utilized generation topology are revealed. Different grid codes requirements are presented and how it could affect the protection considerations is taken into account. Chapter 2 shows the doubly fed induction generator control principles. It provides analysis about the reference frame orientation that represents the main idea behind the control implementation. There is a proposed scheme about orientation implementing that provides stable control against variable frequency voltage if it is voltage oriented based. Step by step built experimental DFIG prototype in the laboratory is introduced for the experimental validation of the proposed work. A simple procedure about experimental DFIG starting is proposed. Theoretical and experimental verification of the DFIG control are also presented. In Chapter 3, the FRT requirement achieving recommendations are introduced. The DFIG conventional protection crowbar scheme for riding through the fault is investigated. The role of modifying the control in FRT satisfying is studied. Chapter 4 proposes a modification strategy in the control for increasing the DFIG immunity to be protected and stay connected during the fault with the aim for riding through the fault. The Egyptian Zaafarana wind farm as a large scale grid integrated system is investigated with the introduced modified control scheme. Chapter 5 finally presents the conclusions and recommendations for the future work.