强风作用下输电线路的脱冰响应研究

Research of Ice-shedding Response of Transmission Lines Under Strong Winds

在强风作用下,输电线路的脱冰过程会产生冲击效应并缩短相间距离,极大增加了电气事故发生的可能性。该文基于新疆某线路局部区段的实际参数,建立强风作用下“导线-绝缘子”的脱冰响应有限元模型,分析了在不同风速、风攻角条件下输电线路脱冰档最大弧垂处的位移、不平衡动张力和各相间的最小距离。结果表明:风攻角对异形覆冰导线的气动系数与风载增大系数存在明显影响;在强风条件下的动张力幅值具有超过设计抗拉强度的情况,存在断线的可能;强风作用下输电线路的脱冰过程相较其初始构型位置是一种向上偏斜的位移过程,存在相间距离显著减小情况,运行时放电风险的概率远远超过无风脱冰工况。该文针对强风作用的输电线路进行研究,探究了复杂工况下的脱冰响应特征和运行时的放电风险,为输电线路在强风天气下进行紧急防冰、除冰技术提供一定的参考。

Under strong wind,the ice-shedding process of transmission lines will produce impact effects and shorten the distance between phases,greatly increasing the possibility of electrical accidents.Based on the actual parameters of a local section of a line in Xinjiang,this paper establishes a finite element model of the ice-shedding response of a"conductor-insulator"under the action of strong winds.It analyses the displacement,unbalanced dynamic tension,and minimum distance between phases of the ice-shedding profile of transmission lines under different wind speeds and wind angles of attack.The results show that the wind angle of attack on the aerodynamic coefficient and wind load increase coefficient of the shaped ice-covered conductor has a significant effect;the dynamic tension amplitude under strong wind conditions has more than the design tensile strength,there is the possibility of wire breakage;the ice-shedding process of transmission line under strong wind is an upward skewed displacement process compared with its initial configuration position,and there is a significant decrease in the inter-phase distance.The probability of the risk of discharging is far more than that of the no wind ice-shedding condition.The probability of discharge risk during operation is much higher than that of the ice-shedding condition without wind.In this paper,the study of transmission lines under strong winds is carried out to investigate the characteristics of the ice-shedding response under complex conditions and the risk of discharge during operation to provide a certain reference for emergency anti-icing and ice-shedding technology of transmission lines under strong winds.