STUDY ON AERODYMICS CHARACTERISTICS OF INDIVIDUAL PITCH CONTROL FOR REDUCTION OF DYNAMIC LOAD ON BLADE
- 주제(키워드) Wind turbine , Individual pitch control , dynamic load
- 발행기관 포항공과대학교 일반대학원
- 지도교수 박현철
- 발행년도 2011
- 학위수여년월 2011. 2
- 학위명 석사
- 학과 및 전공 일반대학원 풍력대학원
- 실제URI http://www.dcollection.net/handler/postech/000000937786
- 본문언어 한국어
- 저작권 포항공과대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
Recently, wind turbine is designed to make greater in size for economic efficiency. More dynamic loads, however, are produced due to increase in wind variations on rotor plane by larger turbine size. There are various factors inducing wind variations such as wind shear, tower shadow, wind misalignment, turbulence and etc. Fatigues, one of the major problems induced by the dynamic loads, not only shorten the system lifetime but also raise cost of production. Therefore, optimal design for minimizing dynamic loads is required. In this study, individual pitch control based on azimuth angle is adopted for reduction of dynamic load. Firstly, an analysis of performance and load using the numerical method based on Blade Element Momentum Theory (BEM) is carried out. And how the wind shear and tower shadow affect aerodynamic loads of turbine is investigated and optimal pitch angle to azimuth for reduction of the aerodynamic load fluctuation is presented. Finally, the effects on individual pitch control will be discussed through the simulation under the actual wind data for 5 minutes.
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목 차
1 서론 ………………………………………………………………………… 1
1.1 연구 배경 ……………………………………………………… 1
1.2 연구 동향 및 목적 ……………………………………………………… 3
2 동하중의 이해 …………………………………………………………… 9
2.1 Wind shear ……………………………………………………… 9
2.2 Tower shadow …………………………………………… 11
2.3 Aerodynamic damping ………………………………………… 12
2.4 Wind misalignment …………………………………………… 15
3 Blade Element Momentum Theory 및 접근 방법 …………… 20
3.1 Blade Element Momentum Theory ………………………… 20
3.2 접근 방법 …………………………………………………… 26
4 Wind Turbine Model …………………………………………………………… 29
5 결과 ……………………………………………………………………… 34
6 결론 ……………………………………………………………………… 44
Reference …………………………………………………………………… 45