分段式结构对风力机塔架振动特性的影响分析

Analysis of the Influence of Sectional Structure on Vibration Characteristics of Wind Turbine Towers

针对分段式结构引起的风力发电塔架失稳问题,利用刚体有限元法建立分段式结构三维动力学模型,提取模态分析的前五阶非零模态的振型,研究在湍流工况下分段式塔架连接处内外法兰的振型特性,通过内外法兰的振型与频谱响应对比,分析分段结构对塔架振动特性的影响。结果表明:分段式的外法兰比内法兰各阶振动位移量小,振动变化幅度小,不易发生共振,外法兰的第1阶振型起主导作用,非线性的扭转变形小,该结果可为塔架在运行过程中避免发生共振及失稳现象提供一定的参考。

The instability problem of the wind power towers induced by the sectional structure is studied.The rigid finite element method is used to establish the three-dimensional dynamic model of the sectional structure.The first five nonzero modals are extracted.The modal characteristics of the inner and outer flanges of the joints of the tower are studied under the turbulent conditions.The results show that the vibration displacements of the outer flange are all smaller than those of the inner flange.The magnitudes of vibration variation are small,so the resonance is unlikely to occur.The first order vibration of the outer flange plays a dominant role in nonlinear torsional deformation.The results provide a reference for the towers to avoid the resonance in the operation process.