基于ASCAT风场数据的中国近海风能资源评估

Wind resource assessment in the offshore of China based on ASCAT wind data

卫星反演海面风场资料能够弥补海上气象测风资料缺乏的不足,对近海风能资源评估具有重要意义。通过ASCAT(Advanced Scatterometer)风速数据与美国及中国近海岸浮标测风资料的对比分析,结果表明,ASCAT风速的均方根误差为1.27 m·s-1。比较利用近海岸浮标逐小时风速及与其相匹配ASCAT瞬时风速计算的各项风能参数,得出ASCAT与浮标的平均风速和风功率密度的残差分别在±0.5 m·s-1和±50 W·m-2以内,该残差占浮标计算结果的比例分别在±8%和±12%以内。使用ASCAT风速资料拟合的Weibull分布函数与浮标的结果较吻合。因此,ASCAT风速资料也能够为海上风能资源评估提供有用的风能参数信息。最后使用ASCAT瞬时风速数据分析了中国近海10 m及70 m高度处的风能资源的空间分布特征,结果表明,台湾海峡平均风速和风功率密度最大。

Wind field data retrieved from the satellite can be a valuable supplement to on-site meas- urement and of great significance for offshore wind resource assessment. The daily wind speed data re- trieved from ASCAT was compared with the buoy data near the coast of the United States and China. Re- sults show that the root mean square error of wind speed was 1.27 m.s-1 in compared with the wind speeds of NDBC buoys. Then, the ASCAT daily data and offshore buoy hourly data were used to calculate the mean wind speed, wind power density and the Weibull probability density function. The residual er- rors of mean wind speed and wind power density associated with ASCAT and individual buoy were respec- tively less than ±0. 5 m·s-1 and ±50 W·m-2. These residual errors of ASCAT compared with buoy mean wind speed and wind power density were respectively less than ±8% and ±12%. The Weibull wind speed distribution of ASCAT data shows good agreement with the result of buoy data. Therefore, ASCAT wind data can provide useful wind parameter information for offshore wind resource assessment. The spatial distribution of wind resources in the coast of China at the height of 10 m and 70 m from 2007 to 2015 were analyzed by using ASCAT wind speeds. The result indicates that the most favorable wind conditions are a- long the coastal area in the Taiwan Strait.