输电线路多分裂导线脱冰动力响应分析

为探究输电线路在脱冰工况下的动力响应状态并对现有的脱冰跳跃经验公式进行改进,运用有限元软件ABAQUS建立四分裂导线有限元模型;基于隐式动力学方法对输电线路脱冰动力响应进行有限元分析,并将分析结果与经验公式计算结果进行对比,对现有的经验公式进行评价和改进,探究部分子导线单独脱冰对输电线路脱冰动力响应的影响,以找出子导线脱冰的最不利工况。研究结果表明:当导线覆冰厚度较小时,导线悬挂点处的支反力随脱冰率单调增加;而当导线覆冰厚度较大时,支反力随脱冰率先增加后减小;在脱冰跳跃经验公式中引入脱冰率作为参数可以提高计算公式的准确性;当部分子导线单独脱冰时,下部子导线脱冰会增加分裂导线发生翻转的风险,从而增加导线磨损和断股的概率。

Analysis on the dynamic response of multi-bundle transmission line subjected to ice-shedding

In order to explore the dynamic response of transmission lines under ice-shedding and improve the existing empirical formula for ice-shedding jumping, the finite element software ABAQUS was used to establish the finite element(FE)model of a 4-bundle conductor. Utilizing the implicit dynamic method, the dynamic response of transmission line after ice-shedding was determined. The result of FE analysis was compared with that was calculated by empirical formulae, based on which the empirical formulae were evaluated and improved. In addition, the influence of ice-shedding occurring on partial sub-wires was investigated, through which the most unfavorable case was obtained. The results showed that when the thickness of ice coating was relatively small, the reaction force at the suspension point of the wire increased monotonously with the ice-shedding rate. If the ice coating was relatively thick, the reaction force would decrease slightly when the ice-sheding rate exceeds a certain value. Additionly, the ice-shedding rate could be used as a parameter in the empirical formula for ice-shedding jumping to improve the accuracy of the formula. When ice-shedding only occured on partial sub-wires, the ice-shedding on lower sub-wire would increase the risk of turning over and thus enlarge the probability of wire abrasion and rupture.