甘肃省风速变化趋势分析

Analysis of wind speed changing trends in Gansu province

近年来,我国风能资源开发增长迅速,甘肃省风能资源储量在全国名列前茅。为降低风电企业投资的风险,需要对当地多年的风速状况进行评估。文中选用甘肃省79个台站1976年至2010年35年的风速资料,30个台站的历史沿革资料,采用T检验法、SNHT(Standard Normal Homogeneity Test)方法及经验正交分解方法(EOF)对甘肃省风速资料进行分析。T检验表明,甘肃省79个站35年的风速资料有3.98%的存在非均一性;资料分析结果表明,甘肃各地风速除陇中及定西部分地区略有上升外,大部分地区风速呈下降趋势,包括风能资源丰富的地区,且下降趋势较明显,其中河西祁连山区风速下降在0.13m/s.10a～0.26m/s.10a之间,河西东部地形平坦区域风速下降在0.13m/s.10a以下;陇南及陇东大部分地区风速下降在0.13m/s.10a以下。甘肃台站风速每十年变化量与本站1976～2010年平均风速比较结果显示:除陇中及定西部分地区风速略有上升,每十年上升在5%～10%之间外,河西祁连山区风速每十年下降在5%～15%之间,河西东部地形平坦区域风速每十年下降在5%以下;陇南及陇东大部分地区风速每十年下降在5%～10%之间。这是今后风电场投资必须要考虑与防范的风险因素之一。

In recent years,development and utilization of China＇s wind energy resource was growing rapidly,and wind resources of Gansu province is among the best in China.Wind power plant once established,must be run many years because life-span of the wind generators design was 20 years.To reduce wind power investment risk,the wind speed of long-terms must be evaluated.This research chose wind data of 79 stations in Gansu province from 1976 to 2010 and the historical evolution information of 30 stations to analyze the wind resouses characters by using t-test,SNHT（Standard Normal Homogeneity Test） method and empirical orthogonal function（EOF） method.The results revealed that 3.98% of the wind data was inhomogenous in data of 79 stations in Gansu province from1976 to 2010.The wind speed decreased distinctly in recent decades in most of Gansu province area,including wind resources abundant region.Some local wind speed was increased slightly.According to the calculation,the result showed that wind speed reduced between 0.13m/s.10a^0.26 m/s.10a every ten years in Hexi Qilian mountain area,while less than 0.13m/s.10a every ten years in east of Hexi corridor;Wind speed reduced less than 0.13m/s.10a every ten years in most east and south of Gansu region.The wind speed increased slightly every ten years between 5%~10% in addition to the central region of Gansu province and part area of Dingxi region,whereas wind speed decreased between 5% ~ 10% in most region of Gansu province.This is the one of risk in future investment in wind farms.