基于模态叠加法的大型风力机典型工况动态特性分析

A study on dynamic characteristics of wind turbines under complex conditions based on the modal superposition method

为提高复杂多变工况下风力机工作性能和使用寿命,建立风力机动态特性计算模型,采用了基于模态叠加法的风力机动态特性计算方法,并对2 MW大型风力机在启动、正常停机、湍流、阵风等典型工况下进行动态特性分析,总结了在不同工况下风力机的动态特性。结果表明:在极端运行阵风作用下风力机的动态特性最为明显,叶尖处的最大动响应的最大值相对于其稳态振幅均值反向增加了359.78%,塔架顶部的最大动应力的最大值相对于稳态应力均值增加了357.63%,该结果为风力机系统进一步优化设计与提高其运行效率及安全性提供了理论依据。

Since the running environment of wind turbines is variable,wind-generating sets are subject to frequent disturbances and dynamic load excitations,resulting in strong vibrations,which are detrimental to the turbines’operating performance and service life.Therefore,it is necessary to analyze their dynamic characteristics in various conditions.We did so by building computer models and adopting a computational method to calculate wind turbines’dynamic characteristics in conditions of start-up,normal stop,turbulence,gusts,etc.We then applied the dynamic characteristics under various conditions.The results show that the wind turbine produced a huge transverse vibration under a transient forcing-flurry.The blade tip’s max displacement response is intensified up to 359.78%under a transient forcing-flurry,which was compared with the mean amplitude under the steady state.The max Von Mises stress at the top of tower is increased by 357.63%in reverse under a transient forcing-flurry,which was compared with the mean stress under the steady state,which should be given great attention in design.The results provide a useful theoretical basis for more optimal design of wind turbines.