向家坝水电站大风特征及影响系统分析

Analysis of Strong Wind Characteristics and Impact Systems at Xiangjiaba Hydropower Station

摘要: 文章利用2018年~2023年向家坝水电站气象站大风资料以及高空观测资料，对向家坝水电站大风特征及其影响系统进行分析，考察大风日数，大风风向、大风风速及其影响系统的特征。结果表明：1) 向家坝水电站大风日数共计112天，年平均日数18.7天；并且大风日数具有明显的季节特征，春夏比秋冬季节显著偏多。2) 大风日大风多出现在21时到次日01时，09时到10时发生概率最小。3) 向家坝水电站风向总体以偏北风、偏西风为主，偏南风、偏东风出现概率均小于2%。4) 风速年际变化小，以7级风占比最大，72.3%。5) 向家坝水电站大风影响系统按季节分为3类：春季的混合型大风，占比34.3%，一般出现在4到5月；夏季的强对流大风，占比49%，主要出现在盛夏；秋、冬季的冷空气大风，占比16.7%。

Abstract: Using the strong wind data and high-altitude observation data from the meteorological station of Xiangjiaba Hydropower Station from 2018 to 2023, this study analyzes the characteristics and impact system of strong winds at Xiangjiaba Hydropower Station, examining the number of strong wind days, wind direction, wind speed, and the characteristics of the impact system. The results show that: 1) The Xiangjiaba Hydropower Station has a total of 112 days of strong winds, with an average of 18.7 days per year; And the number of strong wind days has obvious seasonal characteristics, with significantly more in spring and summer than in autumn and winter. 2) Strong winds often occur from 21:00 to 01:00 the next day, with the lowest probability occurring from 09:00 to 10:00. 3) The wind direction of Xiangjiaba Hydropower Station is generally dominated by north and west winds, with the probability of south and east winds occurring less than 2%. 4) The interannual variation of wind speed is small, with 7-level winds accounting for the largest proportion, 72.3%. 5) The strong wind impact system of Xiangjiaba Hydropower Station is divided into three categories according to seasons: mixed strong winds in spring, accounting for 34.3%, generally occurring from April to May; Strong convective winds in summer, accounting for 49%, mainly occur in midsummer; Cold air and strong winds in autumn and winter account for 16.7%.