Thesis (M.D.S.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 96-105) Also available in print.

This thesis presents and examines the concept that the output of a wound-rotor induction generator (WRIG) can be limited by means of linking to external impedances for wind-turbine generating system application. An 80kW-WRIG is simulated as a model to examine the control of the output power vs. speed characteristic. Model of WRIG derived from per phase equivalent circuit is organized, then it is estimated how much external impedances affect the characteristic of output power for it to approach to a typical wind-turbine curve. Practical tests are performed using 80kW-WRIG in testing lab to validate the simulation data. In addition, a smaller WRIG, connected on same shaft as 80kW-WRIG, is designed to extend the range of wind speed. Also external impedances with smaller WRIG are chosen to extract optimum power from wind-turbine. Finally, passively controlled tandem WRIGs are shown to have the capability to optimize wind-turbine energy extraction when controlled entirely by external impedances. / Graduation date: 2003

Development of variable speed horizontal axis wind turbines has resulted in a need for an analysis code with a rotor speed degree-of-freedom. This study develops a five degree-of-freedom time domain computer code that evaluates blade and rotor, mean and cyclic loads with nonlinear aerodynamics together with atmospheric turbulence as a forcing function. Verification of the model is made by comparison of loads predictions between ESI-80 wind turbine data and analytical solutions. Results show good agreement for mean and cyclic loads and teeter angle excursions. A single-blade point turbulence simulation model is optimized using a three-blade point turbulence simulation model. The optimum point is the 80% radius location, although a multiplying factor is needed to make conservative fatigue cycle predictions of blade bending. ESI-80 start-up and shutdown scenarios are examined, prediction trends matched ESI-80 data. Three generator models are investigated. Results show that generator torque cycles are reduced and yearly energy capture increased by 24% when a variable speed generator is implemented. / Graduation date: 1991

Thesis (Ph. D.)--Open University. BLDSC no. DX218866.

Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Julian, Alexander L. Second Reader: Cristi, Roberto. "December 2009." Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Double Fed Induction Generator (DFIG), Space Vector Modulation (SVM), wind turbine, Field Programmable Gate Array (FPGA), bi-directional power flow. Includes bibliographical references (p. 75). Also available in print.

Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains xiv, 106 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 90-92).

Wind turbines are a cleaner alternative to non-renewable energy, such as fossil fuels, and therefore help to decrease deleterious climate change.[1] Species protection is needed to preserve biodiversity, which is important to all species.[2] It is claimed, how­ever, that between these interests there is a contradiction. Climate change kills birds, but so do wind turbines. According to some, the expansion of wind power is at risk, being hindered by the rules on protected birds, incorrectly interpreted in art­skyddsförordningen[3], the Swedish counterpart to international species conventions and the EU Birds directive[4].[5] The Birds directive and artskyddsförordningen prohibits activi­ties that deliberately kill, capture or disturb migratory birds in the EU (art. 5 Birds directive and 4 § artskyddsförordningen). Mark- och miljööverdomstolen has for some years made the assessment that the establishment and operation of wind turbines may be prohibited by reason of the protection of species, even though the purpose of wind power is to produce electricity and not to kill birds.[6] Due to the legal uncertainty, this essay seeks to find out whether wind energy can fall within art­skyddsförordningens prohibitions and if so, when. This is done through a legal dog­matic method, complemented with a comparative section. The legal situation is not clear, but after a thorough examination of the origin of the Birds directive, previous case law, new disputed ruling by Mark- och miljööver­domstolen, Danish and German case law, ECJ rulings and guidance documents from the European Commission, in total it seems that an inappropriate placement of wind farms or plants can and sometimes should be seen as a deliberate act in respect of the Birds directive and consequently artskyddsförordningen. That is, unless it is possible to under­take precautionary measures, which neutralizes the act. It also appears that art­skyddsförordningen still is to be applied within chapter 2 miljöbalken[7], in the case of species protection. [1] SOU 1999:75, s. 29 f. [2] SOU 2004:37, s. 189. [3] Artskyddsförordningen (2007:845). [4] Directive 2009/147/EC of the European parliament and of the council of 30 November 2009 on the conservation of wild birds. [5] Mark- och miljööverdomstolen har klargjort att vindkraft inte innebär ett avsiktligt dödande eller störande enligt artskyddsförordningen – kommentar av Magnus Fröberg och Hedvig Ekdahl, 2015-01-23, JP Infonet. [6] Se exempelvis MÖD 2013:13. [7] Miljöbalken (1998:808).

The work discussed in this thesis provides a review of pertinent literature, a design methodology, analytical model, concept generation and development, and conclusions about energy harvesting to provide long-term power for bridge health monitoring. The methodology gives structure for acquiring information and parameters to create effective energy harvesters. The methodology is used to create a wind energy harvester to provide long-term power to a wireless communication network. An analytical model is developed so the system can be scaled for different aspects of the network. A proof of concept is constructed to test the methodology's effectiveness, and validate the feasibility and analytical model. / text

No description available.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains ix, 85 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 58-59).