陆上风电机组基础水平震动多自由度分析

The Multiple-degree-of-freedom Analysis of Onshore Wind Turbine and Foundation in Horizontal Vibration

陆上风电机组正朝着高轮毂、长叶片、大容量的方向发展,且在我国地震烈度较高的西北、西南地区,集中式风力发电场正快速发展,这种发展趋势使得风机基础抗震设计在风电场规划设计中显得越来越重要。为使风机基础的抗震设计更加经济、合理,采用底部剪力法和振型分解反应谱法对风机塔架、叶片、轮毂和机舱组成的结构体系进行了动力分析,并对两种方法计算得到的基础水平地震动响应结果进行对比,对比结果表明:对于质量与刚度分布都不均匀的高耸的风电机组结构体系,应用底部剪力法得到的结果与振型分解法相比计算结果偏低,因此,实际工程设计中,若依据底部剪力法计算结果对风电机组基础进行抗震设计,则工程设计偏于不安全。

The onshore wind turbine is developed in the direction of high hub, long blade and large capacity. And centralized wind farms are rapidly developed in both the Northwest and the Southwest with high seismic intensity in our country. This trend of development makes the earthquake-resistant design of the wind turbine foundation become more and more important in planning and design of wind farms. In order to help the aseismic design of the turbine foundation to be more economical and more rational, the base shear method and the mode- superposition response spectrum method were used to conduct a dynamic analysis for the structural system composed of turbine tower, blade, hub and cabin and to compare the results obtained using the two methods. The results comparison shows that for the high structural system with uneven distribution of mass and stiflEaess the calculation result obtained using the base shear method is low as compared with that obtained using the vibration mode decomposition method. Therefore if the calculation result obtained from the base shear method is used to carry out the earthquake-resistant design of the wind turbine foundation, the design is on the unsafe side in the actual engineering design.