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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Controlling hour-long power of wind farms

Li, Pei, 1981- January 2007 (has links)
In attempting to control the power output of a wind farm, it is first necessary to smooth the power fluctuations due to wind turbulence. This is accomplished by spatial smoothing, whereby the high frequency power components of a single wind turbine generator (WTG) is reduced by a factor of N-1/2, where N is the number of WTGs in the farm. For this reason the first part of the thesis is concerned with developing a model of smoothing in a wind farm and justifying it mathematically. / After spatial smoothing, the wind farm output still contains low frequency fluctuations. The second part of the thesis makes use of a combination of: (i) pitch angle control of the turbine blades, (ii) power electronic control of the generators, (iii) spatial filtering and (iv) negative feedback control to remove the low frequency fluctuations. The wind farm output then has the quality to be sold as regulated power which fetches a better economic return than when sold as energy. This, of course, presumes that 1-hour ahead prediction of wind velocity at 1-hour long low variance is available. / The thesis also considers the case when the conditions for regulated power are not predicted. In this situation, the wind farm may opt to use the tracking mode which tracks the slowly time varying non-turbulent wind power. The thesis examines the possibility of diverting some of the wind farm power to implement dynamic performance enhancement strategies, for system damping for example. / The controllability of the wind farm is demonstrated by simulations of a wind farm made up of 24 wind turbine-generators (WTGs) using 1-hour long wind velocity data.
2

Windfarm operations control of windfarm power and kinetic energy discharge as fast reserve /

Keung, Ping-Kwan. January 1900 (has links)
Thesis (M.Eng.). / Written for the Dept. of Electrical and Computer Engineering. Title from title page of PDF (viewed 2008/05/13). Includes bibliographical references.
3

Controlling hour-long power of wind farms

Li, Pei, 1981- January 2007 (has links)
No description available.
4

A high power emulation of a wind farm /

Lalla, Chelsea A. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 49-50). Also available on the World Wide Web.
5

Assessment of methods used to investigate the impact of offshore wind farms on seabirds

Brookes, Kate Louise January 2009 (has links)
This thesis assessed the use of radar as a remote technique for monitoring seabirds in offshore locations.  The study site was in the Moray Firth, Scotland, at the Beatrice oil field, where two 5 MW wind turbines were installed in the summers of 2006 and 2007.  An S-band marine surveillance radar, equipped with commercially available automatic detection and tracking software was installed on the Beatrice Alpha platform to collect ornithological data.  Significant amounts of radar clutter were also recorded in this offshore environment, so bespoke filters were developed, to remove non-avian tracks from the dataset.  Filtered data showed temporal patterns in avian activity at the site, which could be linked to existing knowledge of the use of the site by seabirds.  Flight directions during the breeding season indicated that birds using the site were also attending colonies at the East Caithness cliffs SPA to the north west.  The flight speed parameter included in models of collision between birds and wind turbines was evaluated empirically using radar data.  Ground speed, which is influenced by wind was  highly variable, and was on average 0.707 ms<sup>-1</sup> slower than airspeed, increasing the collisions risk relative to the model’s predictions for many birds. Boat-based visual surveys were used to investigate the impact of turbine installation on the abundance and distribution of birds at the site during the breeding season.  No effect of turbine installation was detected, but environmental variation was shown to have a significant impact on bird abundance.  This demonstrates the difficulty of designing impact studies that can detect the faint signal of an impact, against background variability inherent in marine environments.
6

Assessment of bat mortality and activity at Buffalo Mountain Windfarm, Eastern Tennessee

Fiedler, Jenny K. January 2004 (has links) (PDF)
Thesis (M.S.)--University of Tennessee, Knoxville, 2004. / Title from title page screen (viewed Sept. 22, 2004). Thesis advisor: David Buehler. Document formatted into pages (xiv, 166 p. : ill. (some col.), maps (some col.)). Vita. Includes bibliographical references (p. 79-93).
7

Assessment of methods used to investigate the impact of offshore wind farms on seabirds

Brookes, Kate Louise. January 2009 (has links)
Thesis (Ph.D.)--Aberdeen University, 2009. / Title from web page (viewed on Feb. 18, 2010). Includes bibliographical references.
8

Advanced power electronic for wind-power generation buffering

Montenegro León, Alejandro. January 2005 (has links)
Thesis (Ph.D.)--University of Florida, 2005. / Title from title page of source document. Document formatted into pages; contains 194 pages. Includes vita. Includes bibliographical references.
9

Wind turbine capacity planning approximations for northwest United States utilities

Edinger, Chad L., January 2008 (has links) (PDF)
Thesis (M.S. in electrical engineering)--Washington State University, May 2008. / Includes bibliographical references (p. 90-95).
10

Large-scale integration of wind energy into the power system considering the uncertainty information = Elektrituulikute integreerimine energiasüsteemi arvestades informatsiooni mittetäielikkust /

Agabus, Hannes, January 2009 (has links)
Thesis (doctoral)--Tallinn University of Technology, 2009. / Includes bibliographical references.

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