兆瓦级风力机结构风振系数取值探讨

Study on Wind Vibration Coefficients of Megawatt Turbine Structures

国内外关于风力机塔架设计中风振系数的取值一般不考虑叶片与塔架的结构与气动耦合作用。针对大型风力机系统风振多耦合效应和多振型响应特点,建立某兆瓦级风力机塔架-叶片系统有限元模型,采用改进的叶素-动量理论,模拟考虑旋转效应和塔架-叶片相干性的风力机系统脉动风速时程;基于风振精细化频域计算方法,进行风力机系统动力风振反应计算,探讨了叶片旋转效应的影响、风振系数的取值及其参数变化规律。研究结论为兆瓦级风力机风振系数的确定提供了科学依据。

The wind field caused by structural and aerodynamic coupled effects of blades and tower were not considered in the wind vibration coefficients of wind turbine towers at home and abroad. Aiming at the multi-coupled effects and multi-mode buffeting responses, the integrated finite ele- ment model consisting of the rotor and the tower of megawatt wind turbine was established. The fluctuating wind velocity time history was simulated by the modified harmony superposition method and blade element momentum theory, which considering the blade-tower interaction. U- sing the refined calculating method ＂consistent coupled method＂, which could consider back- ground component, resonant component and cross effect, the wind-induced responses of wind turbine system were calculated, the influence of rotational effect from blades, the choice of value of wind vibration coefficient and its change regularity were discussed. The research conclusions propose the scientific basis for determining wind vibration coefficients of wind turbines.