基于测风塔数据的最大风速与极大风速关系研究

Study on the Relationship Between Maximum and Extreme Wind Speed Based on the Wind Towers Data

利用辽宁省风能资源专业观测网2009年6月至2010年5月26座测风塔10-70 m(部分塔为100 m)高度的逐10 min梯度风观测数据,采用线性相关分析的方法,研究了近地层最大风速和极大风速的关系。结果表明:年内最大风速与极大风速多数出现在同一大风天气过程中,但极大风速并非主要发生在出现最大风速的20 min内;最大风速和极大风速易出现在午后和傍晚;极大风速与最大风速普遍具有较好的线性相关关系,日时距、10 min时距和大风条件下,日时距的相关性最好,平均相关系数达到0.970;不同时距和大风条件下,极大风速与最大风速的比值系数相差不大,但从相关性看可以考虑优先使用日时距样本的最大风速推算极大风速;随着高度的增加,极大风速与最大风速的比值系数减小,10 m高度日极大风速是日最大风速的1.42倍左右,70 m高度则是1.24倍左右,利用最大风速推算不同高度极大风速时不宜采用统一的比值系数。

The relationship between maximum wind speed and extreme wind speed near surface were analyzed using 10-70 m(some of them were 100 m)10 min gradient wind observation data of 26 wind towers from June 2009 to May 2010,by linear correlation analysis method.The results are as follows.The maximum and extreme wind speed often occurs in the same strong wind process,although they do not always happen within the 20 min of maximum speed.They tend to appear in the afternoon and toward evening.The extreme wind speed is better and common linearly related to the maximum wind speed.The mean linear correlation coefficient between daily extreme wind speed and maximum wind speed is the best relative to that of 10 min interval samples series and under strong wind condition,which is 0.970.The ratio coefficient of extreme wind speed and maximum wind speed are of little differences under different interval samples series and strong wind condition,so the daily maximum wind speed data could be used to estimate extreme wind speed.The ratio coefficient of extreme wind speed and maximum wind speed decreases with the increase of height.The ratio coefficient is about 1.42 at 10 m,and about 1.24 at 70 m.Using a single ratio coefficient for different height is not appropriate,when we estimate extreme wind speed by maximum wind speed.