나셀변환함수를 이용한 풍력터빈 출력성능평가 및 불확도 분석

Abstract

A study on power performance testing of a wind turbine which has no met-mast at a distance of 2～4 rotor diameter was carried out using the Nacelle Transfer Function, NTF, according to IEC 61400-12-2. The wind data for this study was measured at HanKyoung wind farm of Jeju Island. The NTF was modeled using the correlation between wind speeds from the met-mast and from the wind turbine nacelle within 2～4 rotor diameter from the met-mast. The NTF was verified by the comparison of estimated Annual Energy Productions, AEPs, and binned power curves. The Nacelle Power Curve, NPC, was derived from the nacelle wind speed data corrected by NTF. The NPC of wind turbine under test and the power curve offered by the turbine manufacturer were compared to check whether the wind turbine is properly generating electricity. Overall the NPC was in good agreement with the manufacturer's power curve. The result showed power performance testing for a wind turbine which has no met-mast at a distance of 2～4 rotor diameter was successfully carried out in compliance with IEC 61400-12-2. An uncertainty of the power curve is caused by measurement equipment, environmental condition, and the number of data. In order to obtain the uncertainty of NPC, additional parameters such as NTF, terrain class, seasonal variation, turbulence, and wind shear were considered. The uncertainty of NPC in compliance with IEC 61400-12-2 and the power curve in compliance with IEC 61400-12-1 were compared. The amount of uncertainty of NPC was larger than that of power curve using met-mast wind speed through all wind speed range because of NTF and method uncertainty.