Frequency-domain synthesis of the fatigue load spectrum for the NPS 100-kW wind turbine

Sutherland, H J; Osgood, R M

Title: Frequency-domain synthesis of the fatigue load spectrum for the NPS 100-kW wind turbine

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Abstract

The LIFE2 code is a fatigue/fracture mechanics code that is specialized to the analysis of wind turbine components. This code permits the analysis of both time series and frequency domain data. Two frequency-domain stress spectra techniques contained in this code are used to analyze the measured frequency loads spectra from the Northern Power Systems 100-kW turbine. In the first, the cycle content is determined using the entire stress spectrum, an FFT and a rainflow counter. In the second technique, the cycle content is determined using time series data for the deterministic (azimuth average) loads and frequency spectra data for the non-deterministic (random) loads. Results of the two techniques are compared to cycle counts obtained directly from time series data. These results provide the wind turbine designer with two techniques for determining the cycle-counts from frequency data and illustrate the accuracy that the designer can expect from various cycle-counting techniques. Moreover, these results illustrate the importance of relatively long time series data on the determination of the high-stress tail in the distribution of the stress cycles.

Authors:

Sutherland, H J ^[1]; Osgood, R M ^[2]

Sandia National Labs., Albuquerque, NM (United States)
National Renewable Energy Lab., Golden, CO (United States)

Publication Date:: Fri Aug 28 00:00:00 EDT 1992

Research Org.:: Sandia National Labs., Albuquerque, NM (United States)

Sponsoring Org.:: USDOE; USDOE, Washington, DC (United States)

OSTI Identifier:: 7147670

Report Number(s):: SAND-92-0611C; CONF-921049-1
ON: DE92040984

DOE Contract Number:: AC04-76DP00789; FC02-86CH10311

Resource Type:: Conference

Resource Relation:: Conference: Windpower '92, Seattle, WA (United States), 19-23 Oct 1992

Country of Publication:: United States

Language:: English

Subject:: 17 WIND ENERGY; WIND TURBINES; FATIGUE; STRESS ANALYSIS; ALGORITHMS; BENDING; FRACTURES; L CODES; STRESSES; COMPUTER CODES; DEFORMATION; EQUIPMENT; FAILURES; MACHINERY; MATHEMATICAL LOGIC; MECHANICAL PROPERTIES; TURBINES; TURBOMACHINERY; 170602* - Wind Energy Engineering- Turbine Design & Operation

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                    Sutherland, H J, and Osgood, R M. Frequency-domain synthesis of the fatigue load spectrum for the NPS 100-kW wind turbine.  United States: N. p., 1992. 
        Web.

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                    Sutherland, H J, & Osgood, R M. Frequency-domain synthesis of the fatigue load spectrum for the NPS 100-kW wind turbine.  United States.

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                    Sutherland, H J, and Osgood, R M. 1992.  
        "Frequency-domain synthesis of the fatigue load spectrum for the NPS 100-kW wind turbine".  United States.

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@article{osti_7147670,

  title        = {Frequency-domain synthesis of the fatigue load spectrum for the NPS 100-kW wind turbine},

  author       = {Sutherland, H J and Osgood, R M},

  abstractNote = {The LIFE2 code is a fatigue/fracture mechanics code that is specialized to the analysis of wind turbine components. This code permits the analysis of both time series and frequency domain data. Two frequency-domain stress spectra techniques contained in this code are used to analyze the measured frequency loads spectra from the Northern Power Systems 100-kW turbine. In the first, the cycle content is determined using the entire stress spectrum, an FFT and a rainflow counter. In the second technique, the cycle content is determined using time series data for the deterministic (azimuth average) loads and frequency spectra data for the non-deterministic (random) loads. Results of the two techniques are compared to cycle counts obtained directly from time series data. These results provide the wind turbine designer with two techniques for determining the cycle-counts from frequency data and illustrate the accuracy that the designer can expect from various cycle-counting techniques. Moreover, these results illustrate the importance of relatively long time series data on the determination of the high-stress tail in the distribution of the stress cycles.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/7147670},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Fri Aug 28 00:00:00 EDT 1992},

  month        = {Fri Aug 28 00:00:00 EDT 1992}

}

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