风速廓线在风电场功率预报中的应用

Discussions on the Application of Wind Profile in Windpower Forecasting

通过分析我国内陆河北省张北县和吉林地区风电场内的风速廓线变化特性发现,各高度间风速的差异分布大体相同:各高度间风速差异由夜间到白天逐渐缩小,在中午达到最小,由白天到夜间逐渐增大,并且在各个阶段又相对稳定,即在日出后由地面向上的热量输送逐渐增强,湍流加强,各层间的风速差异减少,并迅速趋于稳定,直至日落湍流减弱。各层间的风速差异迅速增大,并趋于稳定。这一规律的发现对解释涡轮高度不同时间、相同风速条件下风机出力不同及风电功率建模有重要意义。

Based on an analysis of the characteristics of wind speed profiles in Zhangbei County of Hebei Province and Jilin area in China’s inland,it is found that the distribution of wind speed differences among different heights is basically the same:the wind speed differences among different heights gradually reduce from day to night,reaching the minimum at noon,and they increase from day to night,and remain relatively stable at each stage.That is,after sunrise,the heat transfer from the ground gradually increases and the turbulence strengthens,and the wind speed difference between different layers decreases,and then quickly gets stable until sunset when the turbulence weakens.After sunset,the wind speed differences between different layers quickly increase and turn stable.The discovery of this law helps to explain why the output of the wind turbine is different at the same turbine height with the same wind speed at diffrent times during a day,and it is also of great significance to model the wind power.