风电场不同高度的50年一遇最大和极大风速估算

风电场50年一遇最大和极大风速是决定风电机组极限载荷的关键指标, 也是风电项目开发中机组选型和经济评估的关键指标之一。该文重点从气象学角度, 结合我国风电项目开发的实际情况, 提出5 d最大10 min平均风速取样法, 用Ⅰ型极值概率分布来估算风电场不同高度50年一遇最大风速; 以附近气象站长期的历年最大风速及与风电项目内测风塔同期的逐日最大风速资料, 修正所得结果。再以实测到的大风速段的最大阵风系数, 推算风电场不同高度50年一遇的极大风速。并利用内蒙古巴彦淖尔市乌兰伊力更风电场300 MW项目1年的实测风资料及内蒙古乌拉特中旗气象站的测风资料, 估算乌兰伊力更风电场内不同高度上50年一遇的最大和极大风速。

A Method for Estimating the Extreme 10-minute Average and 3-second Wind Speed with a Recurrence Period of 50 Years at the Different Height in a Wind Farm

The extreme 10 minute average and 3 second wind speed with a recurrence period of 50 years at the hub height on a wind farm is a major index for choosing the wind turbines types. From the viewpoint of meteorology, and linking some developed examples of the wind farm projects in China, the article brings forward a sampling method of the maximum 10 minute average wind speed of 5 days from a whole year actual measured wind speed data of a mast at the wind farm. The method refers to the typeⅠ extreme value distribution and the modification matrix estimating the parameters method, for estimating the extreme 10 minute average wind speed with a recurrence period of 50 years at different heights in a wind farm. Using the same period and long term wind speed data of a nearby meteorological station, the above results can be revised. Since the distribution of wind resource has its own specialty in China, the maximum gust coefficient is reduced when the wind speed gets larger in north area of China, and is bigger than 1.4 when the wind farm is influenced by tropical storm or typhoon. It suggests that using the actual observed maximum gust coefficient of the bigger wind speed to estimate the extreme 3 second wind speed with a recurrence period of 50 years at different heights in a wind farm. This method is applied to estimate the extreme 10 minute average and 3 second wind speed with a recurrence period of 50 years at the different heights in the Wulanyiligeng wind farm 300 MW project in Bayannaoer City, Inner Mongolia. The result reveals that the method is convenient and reliable for the Wulanyiligeng wind farm projects developing.