风电场风速降尺度预报方法对比分析

使用中尺度数值天气预报业务模式9 km和3 km分辨率的模式输出产品，分别应用小尺度模式CALMET模式和双线性插值(BLI)方法将预报风速进行降尺度处理，并对比预报风速和风塔观测资料。结果表明：WRF模式9 km分辨率的模式输出经过CALMET模式降尺度以后得到的风速预报效果比3 km分辨率的模式输出略好。同时，由于中尺度数值预报模式分辨率本身较高，使用BLI也可以得到较好的风速预报。将风速分为0 m·s^-1≤风速<5 m·s^-1，5 m·s^-1≤风速<10 m·s^-1和风速≥10 m·s^-1共3个等级，检验3个风速等级的预报偏差百分比得出，CALMET模式和BLI方法对10 m·s^-1以上的大风的预报效果相对较差；如何对大风预报进行订正对风速预报准确率的提高具有重要的意义。

Comparison analysis of downscaling forecast methods on wind speed in wind power field

The small-scale CALMET model and bilinear interpolation（BLI） method were used to downscale the output of mesoscale numerical weather prediction from the WRF model using both 9 km and 3 km resolutions. The simulated and observed wind speeds were compared. The results show that forecast accuracy of wind speed after downscaling with the CALMET model is higher with 9 km resolution than that with 3 krn resolution. At the same time, the forecast effect of wind speed is also good using the BLI method because of the spatial resolution of me- soscale numerical weather prediction model is high. Wind speed is divided into three levels, namely, 0 m·s^-1≤ wind speed 〈5 m·s^-1,5 m·s^-1≤wind speed 〈 10 m·s^-1and wind speed≥ 10 m·s^-1,and the percentages of pre- diction errors of three levels are tested. It shows that forecast results for wind speed ≥ 10 m·s^-1 are poor no matter whether the CALMET model or the BLI method. It is therefore important to correct strong wind forecast for im- provement of wind speed forecast accuracy.