Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Evaluation of Dynamic Thrust Under Wind Shear in Wind Turbine Below Rated Wind Speed

정격풍속 이하에서 풍력터빈의 윈드쉬어 추력 동하중 개발

  • Lim, Chae-Wook (Dept. of Mechanical Engineering, Hanbat Nat'l Univ.)
  • 임채욱 (한밭대학교 기계공학과)
  • Received : 2015.10.06
  • Accepted : 2016.03.02
  • Published : 2016.04.01
Download PDF
⟨ Previous Next ⟩

Abstract

As wind turbines are getting larger in size with multi-MW capacity, the blades are getting longer, over 40 m, and hence the asymmetric loads produced during the rotation of the rotor blades are increasing. Some factors such as wind shear, tower shadow, and turbulence have an effect on the asymmetric loads on the blades. This paper focuses on a method of modeling the dynamic load acting on a blade because of thrust variation under wind shear. A method that uses thrust coefficient is presented. For this purpose, "wind shear coefficient of thrust variation" is defined and introduced. Further, we calculate the values of the "wind shear coefficient of thrust variation" for a 2 MW on-shore wind turbine, and analyze them for speeds below the rated wind speed. Then, we implement a dynamic model that represents the thrust variation under wind shear on a blade, using MATLAB/Simulink. It is shown that it is possible to express thrust variations on three blades under wind shear by using both thrust coefficient and "wind shear coefficient of thrust variation."

풍력터빈이 MW급으로 대형화되면서 블레이드의 길이가 40미터 이상으로 길어지게 되어, 로터 블레이드가 회전할 때 블레이드에 발생하는 비대칭하중이 증가하게 되었다. 윈드쉬어, 타워 섀도우, 난류풍속 같은 요소들은 블레이드에 이런 비대칭하중 발생에 영향을 미친다. 본 논문은 원드쉬어로 인해 블레이드에 발생하는 추력변동에 의한 동하중을 추력계수를 이용하여 모델링하는 방법에 관한 것이다. 이를 위하여 "윈드쉬어 추력변동 계수"를 정의 및 도입하고, 2MW 육상용 풍력터빈을 대상으로 정격이하의 풍속에서 윈드쉬어 추력변동 계수값을 구하여 분석한다. 구해진 "윈드쉬어 추력변동 계수"와 추력계수를 이용하여 Matlab/Simulink에서 윈드쉬어 동하중 모델을 구현하고, 윈드쉬어에 의해 세 블레이드에 작용하는 추력변동을 추력계수와 "윈드쉬어 추력변동 계수"를 동시에 이용하여 표현할 수 있음을 보인다.

Keywords

References

  1. Hau, E., 2013, Wind Turbines: Fundamentals, Technologies, Application, Economics, Third Translated Edition, Springer-Verlag.
  2. Yaramasu, V., Wu, B., Sen, P. C., Kouro, S. and Narimani, M., 2015, "High-Power Wind Energy Conversion Systems: State-of-the-Art and Emerging Technologies," Proceedings of the IEEE, Vol. 103, No. 5, pp. 740-788. https://doi.org/10.1109/JPROC.2014.2378692
  3. Kaldellis, J. K. and Zafirakis, D., 2011, "The Wind Energy (R)Evolution: A Short Review of a Long History," Renewable Energy, Vol. 36, No. 7, pp. 1887-1901. https://doi.org/10.1016/j.renene.2011.01.002
  4. Maria, I. B., 2009, "The Economics of Wind Energy," Renewable and Sustainable Energy Reviews, Vol. 13, pp. 1372-1382. https://doi.org/10.1016/j.rser.2008.09.004
  5. Burton, T., Jenkins, N., Sharpe, D. and Bossanyi, E., 2011, Wind Energy Handbook, Second Edition, John Wiley & Sons, Ltd.
  6. Manwell, J. F., Mcgowan, J. G. and Rogers, A. L., 2009, Wind Energy Explained: Theory, Design and Application, Second Edition, John Wiley & Sons, Ltd.
  7. Bianchi, F. D., Battista, H. D. and Mantz, R. J., 2007, Wind Turbine Control Systems: Principles, Modelling and Gain Scheduling Design, Springer-Verlag.
  8. Bossanyi, E. A., 2003, "Individual Blade Pitch Control for Load Reduction," Wind Energy, Vol. 6, pp. 119-128. https://doi.org/10.1002/we.76
  9. Selvam, K., Kanev, S., van Wingerden, J. W. and van Engelen, T., 2009, "Feedback-Feedforward Individual Pitch Control for Wind Turbine Load Reduction," International Journal of Robust and Nonlinear Control, Vol. 19, pp. 72-91. https://doi.org/10.1002/rnc.1324
  10. La, Y. H., Nam, Y. S. and Hoon, S. J., 2012, "Individual Pitch Control of NREL 5MW Wind Turbine Blade for Load Reduction," Trans. Korean Soc. Mech. Eng. A, Vol. 36, No. 11, pp. 1427-1432. https://doi.org/10.3795/KSME-A.2012.36.11.1427
  11. Nam, Y. and Choi, H., 2010, "Mechanical Loads Analysis and Control of a MW Wind Turbine," Journal of the Korean Society for Precision Engineering, Vol. 27, No. 9, pp. 26-33.
  12. Hau, E., Langenbrinck, J. and Palz, W., 1993, WEGA Large Wind Turbines, Springer-Verlag.
  13. Staino, A., Basu, B. and Nielsen, S. R. K., 2012, "Actuator Control of Edgewise Vibrations in Wind Turbine Blades," Journal of Sound and Vibration, Vol. 331, pp. 1233-1256. https://doi.org/10.1016/j.jsv.2011.11.003
  14. Bang, J. S., Han, J. W. and Gil, K., 2013, "Development of Programs to Analyze Mechanical Load Data of Wind Turbine Generator Systems and Case Studies on Simulation Data," Trans. Korean Soc. Mech. Eng. B, Vol. 37, No. 8, pp. 789-798. https://doi.org/10.3795/KSME-B.2013.37.8.789
  15. Bossanyi, E. A., 2009, GH Bladed Version 3.82 User Manual.
  16. Lim, C. W. and Seo, K Y., 2010, "Comparison of Response Properties Determined in Two Torque Control Methods for a 2.75-MW Wind Turbine Under Turbulence Wind Speed," Trans. Korean Soc. Mech. Eng. A, Vol. 34, pp. 1885-1891. https://doi.org/10.3795/KSME-A.2010.34.12.1885