基于矩方法的特高压输电塔抗风可靠度分析

WIND-RESISTANT RELIABILITY ANALYSIS OF UHV TRANSMISSION TOWER BASED ON MOMENT METHODS

该文研究特高压输电塔抗风可靠度。基于等效随机静风荷载模型,引入矩方法分析特高压输电塔的抗风体系可靠度。该方法基于等价极值事件,利用统计矩点估计法求解得到等价极值变量前四阶统计矩信息后,即可方便地获得特高压输电塔体系可靠度指标及相应失效概率。1000kV级特高压SZT2钢管塔的数值算例分析表明:1)矩方法简单、高效,将其运用于特高压输电塔抗风可靠度分析切实可行,具有重要的理论意义和工程实用价值;2)在采用点估计法进行等价极值变量统计矩估计时,所取估计点数目应依据失效概率收敛情况而定,并非任意选取或取得越多越好。

This paper analyzes the wind-resistant reliability of UHV transmission tower. A moment method based on the equivalent extreme-value event is introduced to study the system reliability of UHV transmission tower under a random equivalent static wind load. By using point estimate methods for probability moments, the reliability index and the failure probability are obtained through this moment method. A numerical example of 1000kV UHV transmission tower indicates that： 1） being very simple and effective, the moment method can be applied to UHV transmission tower reliability analysis and is of great significance and practical engineering value; 2） the number of estimating points based on the point estimate methods for probability moments should depend on the convergence of failure probability, which means that it is not reasonable to choose freely or to attain the more the better.