基于多维关联信息融合的架空输电线路雷害风险评估方法

Lightning Risk Assessment of Transmission Lines Based on Multidimensional Related Information Fusion

雷电是危害架空线路运行安全的主要因素,为了能够客观、科学地评价输电线路雷害风险,提出一种基于多维关联信息融合的输电线路雷害风险评估方法。首先采用关联规则量化输电线路所处的环境特征因子和本体特征因子与线路雷击故障的关联关系;其次结合信息熵理论确定各特征因子的熵权,采用灰色关联理论依据关联度和熵权确定不同特征因子的基本信度分配函数;然后通过证据理论融合多个特征因子的基本信度分配函数,确定待评估线路的雷击信度值;最后通过映射关系将雷击信度转换成输电线路雷击跳闸率,并确定风险等级。以南方某市级电网为例,利用该电网2003～2015年35～500kV架空输电线路雷击跳闸信息,构建架空输电线路雷害风险评估模型,评估结果与2016年和2017年实际线路雷击故障相吻合,从而证明了该方法的有效性。

Lightning is a major risk factor for overhead transmission lines. In order to evaluate the lightning risk of transmission lines in a scientific way, an evaluation method for strike risk of lightning, based on multidimensional correlation information fusion was proposed. Firstly, the correlation between lightning trip-out and two characteristic factors regarding environmental characteristics and ontology characteristics were quantified. Secondly, the entropy weight of each factor was determined based on the information entropy theory, and the basic reliability distribution function of different characteristic factors were constructed by the grey relational coefficient. Then, the basic reliability distribution fimction of multiple characteristic factors were fused based on evidence theory, and the lightning reliability value of the transmission line was calculated. Finally, the lightning reliability value of the transmission line was mapped to lightning trip-out rate. For example with an actual power grid in the south, the risk assessment model of lightning strike was constructed based on the lightning trip-out data of 35-500kV overhead transmission lines in 2003-2015, and the evaluation result was consistent with the result of lightning trip-out lines in 2016 and 2017. Thus, the validation of the method was demonstrated.