단순 · 복잡 지형에서 허브높이 및 로터등가 풍속을 적용한 풍력발전기 출력성능 비교

Abstract

In order to find the difference between wind turbine power performances derived from hub height wind speed (HHWS) and rotor equivalent wind speed (REWS), an experimental investigation was carried out on complex terrain of Dongbok site, Jeju, and simple terrain of Haengwon site, Jeju. The test wind turbines were a 2 MW wind turbine of Dongbok site and a 1.5 MW wind turbine of Haengwon site, respectively. An 80 m tall met mast corresponding to the hub height of the two turbines was installed each next to the two turbines for capturing wind and meteorological conditions. A LiDAR system was also installed at each site near the met mast for measuring wind conditions. The measurement period was for about 8 months at the two sites. The valid data were used for the analysis after data filtering process. Site assessment was conducted for each site according to IEC 61400-12-1 2nd edition before power performance was tested. The power curve was drawn using HHWS from the met mast, which was compared with that using REWS calculated from LiDAR measurements and HHWS. Annual energy production (AEP) and the capacity factor (CF) were estimated for annual average wind speeds from 4 to 11 m/s using the two types of the power curves. In addition, the relative errors were calculated for the AEP and the CF when the power curve using REWS was a reference. As a result, site calibration was not necessary for simple terrain of Haengwon site, while that was needed for complex terrain of Dongbok site. Since site calibration for Dongbok site with many wind turbines was not possible, power performance test was carried out without site calibration. After data filtering process, in Dongbok site, HHWS was 8.22 m/s, while REWS was 8.18 m/s. The mean relative error of AEP was 1.68 % at annual average wind speeds of 5 - 11 m/s. After data filtering process, in Haengwon site, HHWS and REWS were 11.68 m/s and 11.64 m/s, respectively. The mean relative error of AEP was 0.96 % at annual average wind speeds of 5 - 11 m/s. The difference between CFs using HHWS and REWS was 0.6 % for Dongbok site, while that was 0.3 % for Haengwon site.