输电线路易受大风、覆冰等多种灾害的影响而发生破坏,严重威胁我国能源安全。目前对于输电线路风灾、冰灾的研究多集中于低海拔地区,然而众多西电东送输电线路跨越广袤的高原地区,其中长横担输电塔占有较大比重,为了保障高海拔地区输电线路安全运行,本文依托某±800 kV 特高压直流输电工程,建立了长横担输电塔-线体系精细化模型,基于高海拔地区覆冰条件,分别建立了输电塔和输电线的覆冰工况。同时,考虑高海拔地区空气密度、地形地貌等环境因素的影响,对比分析了高、低海拔地区的风荷载特征。最后,基于高海拔地区覆冰工况和风荷载特点,开展了长横担输电塔-线体系的风振响应分析。结果表明,高海拔地区风剖面较为平缓,长横担输电塔-线体系横担处位移响应大于塔顶的位移响应,冰风荷载作用下结构最大位移响应均出现在横担端部中点处。

Transmission lines are susceptible to damage by a variety of disasters such as high winds and ice cover, which seriously threaten our energy security. At present, the study of wind and ice disasters on transmission lines is mostly focused on low altitude areas, however, many west-east transmission lines cross the vast plateau area, in which the long cross-burden transmission towers occupy a larger proportion, in order to ensure the safe operation of transmission lines in high altitude areas, this paper establishes a long cross-burden transmission tower-line system refinement model relying on a ± 800 kV UHV DC transmission project, based on the ice-covering conditions of the high-altitude areas, respectively, the establishment of the transmission towers and transmission lines of the ice-covered working conditions. At the same time, the wind load characteristics of high and low altitude areas are compared and analysed, taking into account the influence of environmental factors such as air density, topography and geomorphology in high altitude areas. Finally, based on the ice-covering conditions and wind load characteristics in high-altitude areas, the wind vibration response analysis of the long crossbar transmission tower-line system was carried out. The results show that the wind profile at high altitude is relatively gentle, the displacement response at the cross-burden of the long cross-burden transmission tower-line system is larger than that at the top of the tower, and the maximum displacement response of the structure under ice and wind loads occurs at the midpoint of the cross-burden end.

TM75

国家自然科学基金(52178489)；山东省杰出青年科学基金(No. ZR2022JQ27)