الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The increasing levels of doubly-fed induction generator based wind powe penetration threaten power system frequency security due to the lowered syste inertia and the lack of frequency support. A DFIG wind turbine can be made t allocate some of its input power as a reserve and emulate inertia response, withou energy storage, by modifying its controls. This thesis proposes a control strate which maintains a wind power reserve by deloading the turbine while retaining th same pre-pitching steady state operating range of wind speed and reduces the neede gear ratio. Inertia is emulated by providing a fast frequency-dependent overproductio for a suitable time period to rapidly limit decelerating torques on synchronous units Moreover, a governor-like droop is applied to adjust the amount of WTs prima control power. The proposed support is evaluated for different WT parameters. I addition, an operating mode for participation in unit commitment while retainin power reserve is overviewed. Finally, dynamic models of sample slow-respons power systems are built in which all the presented techniques are tested for differen wind penetration levels. Results show significant contribution of DFIG win generation equipped with the proposed support in arresting system frequency deca against low sacrifice of annual energy yield. Beyond a certain wind penetration level system response to power imbalance is seen to be improved relative to the case 0 pure conventional generation.