架空线路导线分层力学模型及应用

Application and Study on Stratified Mechanical Model of Overhead Conductors

架空输电线路导线多为绞线,其应力一般用状态方程计算,计算时不考虑扭绞的影响,将多种外载荷简化为张拉力。以2008年年初南方冰灾对云南电网的影响为背景,提出将材料力学中经典的应力-应变曲线与导线结构特性和工作状态相结合的思路,建立各股线的分层力学模型,推导各层股线的应力分配数值。以常见导线为例进行强度、疲劳的计算分析。计算结果表明,该力学模型与导线实际受力后断股、断线情况较为吻合,且适用于多种绞线,能较好地应用在导线机械性能计算中,可作为导线参数选择、结构优化的数值分析方法。

Most overbead transmission line＇ s conductors are stranded wire, ignoring the effect of twist on its stress, overhead line＇ s stress on conductors is always calculated by status equations in actual projects. Multiple external loads are simplified to tensioning force. On the background of the southern ice disaster＇ s effect on Yunnan Power Grid at the beginning of 2008, the paper put forward a thought that combined the classical stressstrain curve in material dynamics with conductor structures and their working status to establish a stratified mechanical model, and derived the stress distribution stress on each strand. Using a common conductor as an example, a calculation analysis on strength and fatigue were carded out. The result shows that the model coincides with the wire breakage and rupture under stress, and is applicable for multiple stranded wires. It can be used in calculation of conductor mechanical properties, and offers a way of analyzing data for conductor parameter selection and the structure optimization.