大型风电场实地测风数据精细化分析方法

Detailed Analysis Method of the On-site Wind Resource Data for Large-scale Wind Farm

“双碳”战略目标下,基地化、规模化开发已成为中国风电发展的主力和特色模式,研究大型风电场大气边界层流动的区域性风况变化与热力状态特征,对风能资源的精准评估与风电机组优化选址具有重要意义。提出了一种适用于大型风电场多点位测风条件下的实测数据精细化分析方法,通过对优选参考测风塔的条件性风况筛选,结合局地大气稳定度的判别,构建了中性、稳定、不稳定状态驱动下多点位测风数据集,探究了条件性风况下中性大气稳定度的湍流强度临界值,研究了不同大气稳定度下实地测风的空间变化特点。结果表明:在条件性风况的驱动下,参考测风塔处的风切变和湍流强度水平随着大气稳定度的提高,分别呈增大和降低趋势,中性状态下的风速与湍流强度廓线并不等同于包含所有热力状态数据的系综平均;不稳定大气驱动下,各测风塔处的风统计特征较中性大气下的变化幅度与趋势,相比于稳定大气驱动下的结果更为明显和一致。该方法得到的多点位测风数据集,可为特定风况下湍流模型与数值计算方法的适应性开发和修正,提供定量的数据验证支撑。

The development of the large-scale wind farm or wind power base has become the main stream and innovative features under the “dual carbon goals” strategy in China.It is of great significance to investigate the regional wind variation and thermal status of the atmospheric boundary layer flow over the long-span wind site,in order to perform the wind resource assessment accurately and conduct the wind turbine micro-sitting optimally.Aiming at the special circumstance of the wind resource development,a detailed analysis method of the on-site wind resource data from multiple measure locations for the large-scale wind farm was proposed.The conditional wind statistics was filtered based on the reference met-tower and the data with local atmospheric stability were sorted out.The wind data sets under neutral,stable and unstable stabilities corresponded to the different met-towers were established accordingly.The threshold of turbulence intensity for the neutral stability driven by the conditional wind was explored.The special variations of wind flow within the wind farm site under different atmospheric stabilities were investigated.The results show that the wind shear and turbulence intensity level at the reference met-tower location show increasing and decreasing trends,respectively,along with the atmosphere changes from unstable to stable states driven by the conditional wind.The mean wind speed and turbulence intensity profiles are quite different from those obtained by the ensemble average of the datasets with all stability states.The wind statistic differences at each met-tower between the unstable and neutral atmospheres,show more obvious than those between stable and neutral atmosphere.It is concluded that the wind datasets of multiple met-tower locations obtained by the proposed method can provide quantitative data verification for the adaptive development and improvement of the turbulence model in numerical method under specific wind driving conditions.