基于进化策略 投影寻踪算法的考虑多因素的输电线路覆冰灾害风险评估

针对目前输电线路覆冰灾害风险评估模型存在忽略地形因子、权重取值人为主观因素较大等缺陷,以保证所考虑风险因子完整性为前提,综合考虑坡度、粗糙度、高程、气温、相对湿度、风速、实测覆冰厚度值、覆冰比值、冰区量级9个风险因子,通过组合投影方式,将多维数据投影到低维空间,并结合进化策略对投影寻踪指标函数求最优解,以256条线路2个冰期样本数据为例,得出输电线路覆冰灾害风险目标5级评价标准。结果表明:当进化代数达到311代时,目标函数值达到最优0.513 4;同时,Ⅳ风险等级及其以上线路占总线路的30.5%;最后以220 kV石上线为例,验证了所建立输电线路覆冰灾害风险评价模型结果的适用性以及准确性。本文方法能够有效地对输电线路覆冰风险进行评价,对实现输电线路防冰管控工作的精益化提升具有重要意义。

Evolutionary Strategy-Projection Pursuit Algorithms for Risk Assessment of Transmission Line Icing Disaster Considering Multi-factors

In view of the defects of neglecting topographic factors and taking weight as subjective factors in the current risk assessment model of transmission line icing disaster, this paper takes the integrity of the risk factors considered as the premise, comprehensively considers nine risk factors, including slope, roughness, elevation, temperature, relative humidity, wind speed, measured icing thickness, icing ratio and ice area magnitude, through combined projection. In this way, multi-dimensional data are projected into low-dimensional space, and the optimal solution of projection pursuit index function is obtained by combining evolutionary strategy. Taking 256 lines as an example, the 5-level evaluation criteria of transmission line icing disaster risk target are obtained. The results show that when the evolutionary algebra reaches 311 generations, the objective function reaches the optimal value of 0.5134. At the same time, the risk grade IV and above lines account for 30.5% of the bus circuit. Finally, taking the 220 kV Shishang line as an example, this paper verifies the applicability and accuracy of the risk assessment model of transmission line icing disaster established in this paper. The conclusions drawn in this paper can effectively evaluate the risk of transmission line icing, which is of great significance for the realization of lean management and control of transmission line icing.