高压线缆系统非线性建模理论与动力学分析方法研究

When overhead transmission line to power transmission tower in tension pay-off way, it is necessary to set up protective cross frame to prevent breaking of the road or bridges under the wire. This is a rigid-flexible system contains large deformation flexible body, large scale structure, nonlinear constrains and complex contact problems. This investigation will firstly focus on the modeling of the geometrical and material nonlinearity of the wire. A new fully parameterized absolute nodal coordinate formulation beam element will be proposed. It is able to describe the local deformation of the cross section and the composite structure of the wire and it is easy to apply the initial strain and viscoelastic material property to the wire. Then the research on the model order reduction of the iron tower and the cross section will be proceeded based on the conditions that the complex sliding joints and impact contact exist respectively. The co-simulation of the whole system will be done and the demonstrative experiment will be carried out. This investigation can be seen as the extension and innovation of the existing flexible multi-body system dynamic modeling theory and method. At the same time, the result of this investigation will provide technical support for the electricity construction and the design standard of the cross frame. In other word, the social benefits will be significant.

特高压线路架设施工使用张力放线的方式将导线架设到输电铁塔上。若导线发生张力失效事故，会依次穿过铁塔后掉落在下方起保护作用的格构式跨越架上。本项目拟针对导线-铁塔-跨越架构成的含有大变形体、大型钢结构以及非线性滑移约束和复杂接触的刚柔耦合线缆系统，开展以下方面的研究：首先基于绝对节点坐标理论构造柱坐标系描述的圆截面全参数梁单元并将其应用于输电导线几何与材料非线性的建模。而后根据输电铁塔和跨越架分别与导线间存在非线性滑移约束和复杂接触的特点提出相应的降阶策略。最终进行导线-铁塔-跨越架联合动力学分析方法研究并开展验证实验完善所提理论与方法。本项目是对多柔体系统动力学建模理论的拓展与创新，同时为特高压线路建设提供安全技术保障，为跨越架设计规范的编制提供指导，具有很高的理论价值和显著的社会效益。

本项目针对高压输电线缆架设施工过程中发生张力失效事故，对下方起保护作用的跨越架发生冲击的过程进行动力学建模与分析，开展了以下方面的研究工作。1.构造了圆形截面全参数绝对节点坐标梁单元并提出了将其应用于输电导线分层复合材料特性以及大变形几何非线性建模的系统性方法；2.提出了基于分段连续节点坐标缆索单元的输电导线张力释放过程动力学分析方法，采用先进行静力学求解而后将结果作为动力学求解初值的方法；3.提出了输电导线与铁塔间非线性滑移约束的建模与静、动力学求解策略；4.提出了输电导线与跨越架之间高效接触检测算法；5.建立了基于绝对节点坐标法和自由界面模态综合法的大型柔性多体系统降阶方法；6.开展了导线冲击抱杆的动力学验证实验。通过本项目资助，形成了高压输电线缆在发生张力失效后掉落在跨越架上这一系列包含几何与材料非线性及柔性体间碰撞冲击的复杂动力学行为进行建模、求解、分析的方法。本项目的研究成果拓展了柔性多体系统的理论，丰富了其应用场景。为保障国家特高压输电线路建设的施工安全与规范提供了理论依据。