基于室外导线节段模型的输电线路覆冰与脱冰过程试验研究

Field experiments on ice-accretion and ice-shedding processes of power transmission lines based on a conductor segment model

输电线路通常需要跨越峡谷及山地等险峻复杂地形,线路脱冰动力响应的现场实测往往成本较大且精度难以保证。而室内缩尺模型试验则难以真实重现自然地貌及气象条件。为实现对某500kV高压输电线路覆冰、脱冰物理过程的高效低成本模拟,该文基于模态叠加法和动力相似关系自主设计自然条件下多分裂导线节段模型装置。采用弹簧系统提供可调的垂直、水平和扭转刚度,以模拟原型输电线路的三自由度动态特性。在线路场址布置导线节段模型装置,通过开展人工模拟试验验证该装置在模拟脱冰位移响应方面的有效性。基于真实冰风气象环境中的多分裂导线节段模型装置,采用计算机视觉技术实现对导线三次真实覆冰、脱冰过程的有效观测。为多分裂导线的覆冰、脱冰观测及试验研究提供新的技术手段。

Power transmission lines often run through steep and complex terrains such as canyons and mountains.The field measurement on ice shedding of power transmission lines is costly and it is difficult to ensure the measurement accuracy.In addition,it is also difficult for indoor scale model tests to reproduce natural terrain and meteorological conditions.In order to achieve efficient and low-cost field measurement,a multi-bundled conductor segment model is originally developed for simulating ice-accretion and ice-shedding processes of a 500 kV high-voltage transmission line based on the modal superposition method and dynamic similarity relationship.A spring system is designed to provide adjustable vertical,horizontal and torsional stiffness for simulating the three-degree-of-freedom dynamic characteristics of the prototype transmission line.The conductor segment model device is set up at the site of the 500 kV high-voltage transmission line,and the effectiveness of the model device for simulating the displacement response due to ice shedding is verified by conducting artificial ice-shedding tests.Three real processes of icing and ice-shedding of conductors are captured by the computer vison monitoring based on the multi-bundled conductor segment model device under the nature wind and ice meteorological environment.It provides a new technical means for the field experiment of ice-accretion and ice-shedding processes of multi-bundled conductors.