1 000 kV特高压变电构架风力系数及风荷载竖向分布

1 000 kV 特高压变电构架是我国新型变电站设备,风荷载及其效应影响其结构设计。文章通过高频天平测力风洞试验数据计算整体与节段结构体轴和风轴上的风力系数,获得结构风荷载的竖向分布,探究地貌和风向角对风力系数和风荷载竖向分布的影响规律,并提出风荷载最不利分布的计算方法。研究表明:均匀流和 A 类地貌对结构体轴和风轴风力系数影响最大;在频域分析中,紊流场风力系数功率谱密度大于均匀流场对应值,3 类风场的第 1 阶频率均在 0.3~0.4 Hz;同时 B 类地貌下结构风荷载竖向分布大于 A 类地貌分布且结构最不利位置在 31、70 m 高度,0°和 90°风向对结构风力系数、阻力系数、升力系数和风荷载竖向分布较为不利。

The 1 000 kV ultra-high voltage (UHV) substation frame is a new type of substation equipment in China, and its structural design is influenced by wind load and its effects. This paper calculates the wind coefficients at the body axis and wind axis of the integral and segmented structure by using the high-frequency force balance wind tunnel test data, and then obtains the vertical distribution of wind loads on the structure, and examines the effects of the terrains and the wind incidence angles on the wind force coefficients and the vertical distribution of wind loads. The calculation method of the most unfavorable distribution of wind loads is proposed. The research shows that the uniform flow and terrain A have the greatest influence on the wind coefficients at the structural body axis and wind axis. In the frequency domain analysis, the power spectral densities of the wind force coefficients of the turbulent field are greater than the corresponding values of the uniform flow field, and the first-order frequencies of the three types of wind fields are in the range of 0.3 Hz to 0.4 Hz. At the same time, the vertical distribution of wind loads on the structure under terrain B is greater than that under terrain A. terrain A, and the most unfavorable positions of the structure are at heights of 31 m and 70 m. The $ 0^{\circ} $ and $ 90^{\circ} $ wind direction are unfavorable to the structural wind force coefficients, drag coefficients, lift coefficients and vertical distribution of wind loads.