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Design of Individual Pitch Control and Fatigue Analysis of Wind Turbine

풍력발전시스템 개별피치제어설계 및 피로해석에 관한 연구

  • Jeon, Gyeong Eon (Dept. of Aerospace Engineering, Chonbuk Nat'l Univ.) ;
  • No, Tae Soo (Dept. of Aerospace Engineering, Chonbuk Nat'l Univ.) ;
  • Kim, Guk Sun (Dept. of Aerospace Engineering, Chonbuk Nat'l Univ.)
  • 전경언 (전북대학교 항공우주공학과) ;
  • 노태수 (전북대학교 항공우주공학과) ;
  • 김국선 (전북대학교 항공우주공학과)
  • Received : 2013.04.16
  • Accepted : 2013.11.14
  • Published : 2014.01.01

Abstract

Structural loading on a wind turbine is due to cyclic loads acting on the blades under turbulence and periodic wind field. The structural loading generates fatigue damage and fatigue failure of the wind turbine. The individual pitch control(IPC) is an efficient control method for reducing structural loading. In this paper, we present an IPC design method using Decentralized LQR(DLQR) and Disturbance accommodating control(DAC). DLQR is used for regulating rotor speed and DAC is used for canceling out disturbances. The performance of the proposed IPC is compared with CPC, which was designed with a gain-scheduled PI controller. We confirm the effect of fatigue load reduction with the use of damage equivalent load(DEL).

로터에 작용하는 불균형한 반복 하중은 풍력발전기에 구조적 하중을 발생시키고 이러한 하중이 구조물에 지속적으로 누적되면 피로 파괴와 수명 단축을 발생시킨다. Individual pitch control(IPC)는 이러한 구조적 하중을 저감시키고 풍력발전기의 작동 수명 연장에 효과가 있는 제어 방법이다. 본 연구에서는 Decentralized LQR(DLQR)과 Disturbance accommodating control(DAC)를 이용한 IPC 설계를 제시한다. DLQR은 로터 회전속도 제어를 위해 사용하였고 DAC는 블레이드에 외란으로 작용하는 바람(난류) 효과를 상쇄하도록 구성하였다. 제시된 IPC제어기의 구조적 하중 저감 효과는 Gain-scheduled PI로 설계된 Collective pitch control(CPC)과 비교하여 확인하였다. 또한, IPC의 구조물 하중 저감 효과를 확인하기 위해 피로 누적에 의한 손상정도를 나타내는 피로등가하중(DEL)을 이용하였다.

Keywords

References

  1. Hand, M. M., 2003 "Mitigation of Wind Turbine/ Vortex Interaction Using Disturbance Accommodating Control," Ph.D. Dissertation, Department of Mechanical Engineering University of Colorado. Boulder, CO, USA, NREL/TP-500-35172.
  2. Namik, H., 1994, "Individual Blade Pitch and Disturbance Accommodating Control of Floating Offshore Wind Turbines," Ph.D. The University of Auckland.
  3. Wright, A. D., 2004, "Modern Control Design for Flexible Wind Turbines," National Renewable energy Laboratory/TP-500-35816.
  4. Jeon, G. E., No, T. S., Kim, G. S. and Kim, J. Y., 2012, "Design of DAC and Decentralized LQR for Wind Turbine Individual Pitch Control" 2012 KWEA Korea Wind Energy Spring Conference, May, 16.
  5. Pahm, T.-K., Nam, Y.S., Kim, H.G. and Son, J.H., 2012, "LQR Control for a Multi-MW Wind Turbine," World Academy of Science, Engineering and Technology 62.
  6. Jonkman, J. M., 2007, "Dynamics Modeling and Loads Analysis of an Offshore Floating Wind Turbines," NREL/TP-500-41958.
  7. Stava, O. M., 2012, "Fatigue Analysis of Offshore Wind Turbine," Konstruksjoner og materialer, Ph.D Thesis.
  8. Bossanyi, E. A., 2005, "Further Load Reduction with Individual Pitch Control," Wind Energy 481-485.
  9. Bossanyi, E. A., 2003, "Wind Turbine Control for Load Reduction," Wind Energy, Vol. 6, No. 3, pp. 229-244. https://doi.org/10.1002/we.95
  10. Olagnon, M. and Guede, Z., 2008, "Rainflow Fatigue Analysis For Loads With Mutimodal Power Spectral Densities," Archive Institutionele de l'lfremer, April-July 2008, Vol. 21, Issue 2-3, pp. 160-176.
  11. International Electrotechnical Commission 2001, "IEC 61400-13, Measurement of Mechanical Loads," First edition.