基于风速风向联合概率的输电线路漂浮物故障风险评估

Risk Assessment of Transmission Lines Trip-out Caused by Floaters Based on Joint Probability Density Function of Extreme Wind Speed and Direction

为了精确评估漂浮物对输电线路跳闸的影响,提出了一种以极值风速风向联合概率密度函数（JPDF）为基础,结合线路特征参数和地理环境因素的输电线路漂浮物故障风险评估方法。首先以极值风速及其风向角为双变量计算极值风速风向联合概率密度;其次根据线路特征参数、线路与风向夹角和输电走廊局部环境状况计算故障敏感性参数;最后结合该区域的漂浮物密度计算线路各段在不同月份的跳闸率,从而实现了漂浮物跳闸时空风险评估。以南方某市级输电网络为例,计算其线路漂浮物跳闸率,并根据跳闸率划分风险等级,风险等级与实际运行中线路漂浮物跳闸结果吻合度较高,证明了该方法的有效性。

An approach based on Joint Probability Density Function（JPDF） of extreme wind speed and direction,combined with the characteristic parameters of lines and geographical environment factors,is proposed in order to evaluate the risk of transmission lines trip-out caused by floaters.Firstly,the JPDF of extreme wind speed and direction is calculated by two variables,namely the extreme wind speed and its wind direction angle.Secondly,the fault sensitivity parameters are calculated according to the characteristic parameters of lines,the angle between line and wind direction,and the local environment of the transmission corridor.Finally,based on the distribution of floater density in the area,the probability of the trip-out caused by floaters is calculated in different months and line segments,and the evaluation of space-time risk for line trip-out caused by floaters is realized.Based on the proposed method,the probability of line trip-out caused by floaters is calculated and the risk grade is determined according to the probability by the example of one of the power grids in a south city.The results show that the risk grade is basically consistent with the operation data,and the effectiveness of the proposed method is proved.