Full Content is available to subscribers

Subscribe/Learn More  >

Active Gearing System for Wind Turbines

[+] Author Affiliations
Daniel McMullan, Anh Dao, Daniel Brooking, J. Mark Weller, M. Salim Azzouz

Midwestern State University, Wichita Falls, TX

Paper No. IMECE2011-65011, pp. 1259-1266; 8 pages
  • ASME 2011 International Mechanical Engineering Congress and Exposition
  • Volume 4: Energy Systems Analysis, Thermodynamics and Sustainability; Combustion Science and Engineering; Nanoengineering for Energy, Parts A and B
  • Denver, Colorado, USA, November 11–17, 2011
  • Conference Sponsors: ASME
  • ISBN: 978-0-7918-5490-7
  • Copyright © 2011 by ASME


The purpose of this research paper is to investigate the possibility of improving the efficiency of wind turbines by taking advantage of the wind speed variability. An active epicycloids gearbox system allowing a variable speed at the input shaft and delivering a constant speed at the output shaft is proposed herein. The gearing system consists of an assembly of spur and ring gears run and controlled by an electrical motor. The system acts as a continuously variable transmission (CVT) between the wind turbine hub and the electricity generator which requires an entry speed corresponding to an electrical grid frequency of 60 Hz. The active gearing system is designed using CAD software, and the gearing design theory is used to dimension the proposed epicycloids system. The kinematic gearing theory is used to establish the different gearing ratios of the system, and the kinematic velocity relationships between the gearing system stages. The forces and torques acting on the gearing system are computed using the equilibrium equations. Ideally, the electrical power consumed by the regulating motor system is minimal so that a maximum percentage of the generated electrical power is supplied to the electricity grid. The advantage of this gearbox configuration is that the power consumed by the regulating motor will be theoretically close to zero when the wind speed is about 10.5 mph, which is the average wind speed for many areas where wind turbines are installed. As the wind speed moves away from its mentioned average, the gearbox electrical controls activate a regulating motor to secure a constant speed at the generator input. Currently, a prototype of the proposed system is under tests and experimental data has already shown the constancy of the angular velocity at the generator input. The measurements of the mechanical power distribution between the different components of the system are still underway. A prony-break system is currently used for this purpose. It is expected that within a defined range of the hub angular velocities, the power absorbed by the regulating motor remains a small fraction of the power delivered by the electricity generator.

Copyright © 2011 by ASME
Topics: Wind turbines



Interactive Graphics


Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In