Damage measurements on the NWTC direct-drive, variable-speed test bed Metadata

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  • Main Title Damage measurements on the NWTC direct-drive, variable-speed test bed


  • Author: Sutherland, H.J.
    Creator Type: Personal
    Creator Info: Sandia National Lab., Albuquerque, NM (United States)
  • Author: Carlin, P.W.
    Creator Type: Personal
    Creator Info: National Renewable Energy Lab., Golden, CO (United States)


  • Sponsor: United States. Department of Energy. Office of Energy Efficiency and Renewable Energy.
    Contributor Type: Organization
    Contributor Info: USDOE Assistant Secretary for Energy Efficiency and Renewable Energy, Washington, DC (United States)


  • Name: Sandia National Laboratories
    Place of Publication: Albuquerque, New Mexico
    Additional Info: Sandia National Labs., Albuquerque, NM (United States)


  • Creation: 1998-12-31


  • English


  • Content Description: The NWTC (National Wind Technology Center) Variable-Speed Test Bed turbine is a three-bladed, 10-meter, downwind machine that can be run in either fixed-speed or variable-speed mode. In the variable-speed mode, the generator torque is regulated, using a discrete-stepped load bank to maximize the turbine`s power coefficient. At rated power, a second control loop that uses blade pitch to maintain rotor speed essentially as before, i.e., using the load bank to maintain either generator power or (optionally) generator torque. In this paper, the authors will use this turbine to study the effect of variable-speed operation on blade damage. Using time-series data obtained from blade flap and edge strain gauges, the load spectrum for the turbine is developed using rainflow counting techniques. Miner`s rule is then used to determine the damage rates for variable-speed and fixed-speed operation. The results illustrate that the controller algorithm used with this turbine introduces relatively large load cycles into the blade that significantly reduce its service lifetime, while power production is only marginally increased.
  • Physical Description: 8 p.


  • Keyword: Wind Turbines
  • Keyword: Damage
  • Keyword: Speed Regulators
  • Keyword: System Failure Analysis
  • STI Subject Categories: 17 Wind Energy
  • Keyword: Turbine Blades


  • Conference: 17. ASME wind energy symposium, Reno, NV (United States), 12-15 Jan 1998


  • Name: Office of Scientific & Technical Information Technical Reports
    Code: OSTI


  • Name: UNT Libraries Government Documents Department
    Code: UNTGD

Resource Type

  • Article


  • Text


  • Other: DE98000923
  • Report No.: SAND--97-2590C
  • Report No.: CONF-980104--
  • Grant Number: AC04-94AL85000
  • Office of Scientific & Technical Information Report Number: 560811
  • Archival Resource Key: ark:/67531/metadc690527


  • Display Note: OSTI as DE98000923