الفهرس 
chapter 1Only 14 pages are availabe for public view
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Abstract
Wind power is the most reliable and developed renewable energy source. The share of wind power with respect to total installed power capacity is increasing worldwide. The doubly fed induction generator (DFIG) based wind turbine with variable speed control scheme is the most popular wind power generator in the wind power industry. This machine can be operated either in grid connected or standalone mode and is comprised of two back-to-back converters. One converter connects the DFIG stator to the grid, and the second converter is connected to the rotor of the machine through a DC-link capacitor.
The work presented in this thesis includes control system design , analysis and grid synchronization, using a phase licked loop (PLL) technique, of a DFIG driven by a wind turbine using stator voltage oriented frames. The dynamic model is used to obtain the relationship between the d-q currents and real/reactive power references in particular orientation frame. The wind turbine driving torqe is modeled by considering typical wind turbine aerodynamic characteristics under variable wind speed. A speed control system has been designed to analyze maximum power extraction from a DFIG for a particular wind speed.