山区峡谷地形下柔性支撑光伏阵列的风振特性研究

WIND-INDUCED VIBRATION ANALYSIS OF FLEXIBLE PHOTOVOLTAIC SUPPORT STRUCTURE UNDER MOUNTAIN CANYON TERRAIN

为准确考察柔性支撑光伏阵列的整体抗风性能,该文以某光伏发电项目为研究对象,建立“系泊-光伏组件阵列结构”整体模型,基于Davenport风谱,采用AR自回归技术模拟脉动风荷载进行风振响应和流场分析。结果表明:1)迎风面边缘体型系数最大,沿风向呈递减趋势,具有明显梯度。因此,光伏组件表面风荷载分布是非均匀性的,这是光伏组件在风场作用下产生扭摆振动的主要原因。2)阵列外围光伏组件受风场作用的影响最大,为危险区,设计阶段应给予足够重视。3)此光伏阵列风振响应最大幅值约为8.0 cm,与实际工程情况符合;板体之间相互碰撞、发生隐裂的概率较低,柔性承托结构可在部分地形劣态地区作为刚性支撑结构的替代。4)柔性支撑下光伏组件之间纵横向连接紧密,结构刚度分布均匀,风致响应趋势相同,各光伏组件风振响应均以低频振动为主,风振系数为1.7。5)地锚拖曳结构对光伏组件位移有显著约束作用,因此,地锚数量、位置的分布调整可作为柔性支撑下光伏组件阵列的结构优化首选条件。

In order to accurately investigate the overall wind resistance performance of flexible support photovoltaic array this paper takes a photovoltaic power project as the research object,establishes the overall model of solar photovoltaic arrays with pre-tensioning of flexible ropes,the flow field and wind-induced vibration response are analyzed based on Davenport wind spectrum and auto-regressive technique.The results showe that the wind pressure shape coefficient is decreased along the wind direction with obvious gradient. Therefore,the wind load distribution on the surface of photovoltaic module is non-uniform,which is the main cause of torsional vibration of photovoltaic modules under the action of wind. The photovoltaic modules at the edge of array are most affected by the wind field,which is the dangerous area and should be given sufficient attention in this design. The response amplitude of wind-induce vibration is about 8.0 cm,and the probability of collision and hidden crack between photovoltaic module is low. It shows that the flexible support structure can be used as a substitute for rigid support. The structural stiffness of the flexible support photovoltaic arrays is uniform distributed. So the wind-induced vibration response trend of all photovoltaic modules is the same,and it's mainly low-frequency vibration,the wind-induced vibration coefficient is about 1.7.Anchor cable has a significant constraint effect on vibration,Therefore,the distribution adjustment of cable number and position can be used as the preferred condition for structural optimization.