Accuracy Assessment of Four-Beam Nacelle LIDAR Measurements in Complex Terrain

복잡지형에서 4빔 나셀 라이다 측정 데이터의 정확도 평가

  • 신동헌 (제주대학교 대학원 풍력특성화협동과정) ;
  • 고경남 (제주대학교 대학원 풍력공학부) ;
  • 강민상 (제주에너지공사 에너지연구기술센터) ;
  • 류동훈 (한국산업기술시험원 산업표준본부) ;
  • 강문종 ((사)한국선급 미래기술연구팀) ;
  • 김효정 ((주)도암엔지니어링 기업부설연구소)
  • Received : 2018.04.26
  • Accepted : 2018.06.05
  • Published : 2018.06.30

Abstract

In order to assess the accuracy of four-beam nacelle light detection and ranging (LIDAR) measurements, a field measurement campaign was carried out in Dongbok wind farm on Jeju Island. The four-beam nacelle LIDAR was set up on the nacelle of a test wind turbine of HJWT 2,000 kW with an 80 m hub height for this investigation. The ground-based LIDAR was situated at three times the rotor diameter of the test wind turbine. First, the ground-based LIDAR measurements were verified by comparing them with neighboring 80-meter-tall met mast wind data. Then, the four-beam nacelle LIDAR measurements were compared with the ground-based LIDAR measurements. The carrier to noise ratio (CNR) variation was analyzed in terms of weather conditions (temperature, pressure, humidity) and mechanical movement (blade rotation, tilt variation of wind turbine). Measurement deviations were also analyzed according to data availability. Based on the analysis results of the characteristics of LIDAR measurements, reliable ground-based and nacelle LIDARs data sets were chosen for linear regression analysis. As a result, it was confirmed that the average CNR signals were higher than the CNR threshold in various weather conditions. The mechanical movement did not cause LIDAR measurement deviation. The correlation between wind data by nacelle and ground-based LIDARs was considerably high with a regression coefficient of 1.01 and coefficient of determination of 0.98.

Keywords

Acknowledgement

Grant : 나셀 라이다를 이용한 풍력발전설비 및 풍력단지 출력성능측 정 기술개발, 육, 해상 풍력터빈 신뢰성 및 발전량 향상을 위한 O&M 기술 고급트랙

Supported by : 한국에너지기술평가원 (KETEP)

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