Abstract:

First,damping ratio identification formula was derivate by the wind turbine blade attenuation vibration equivalent to the cantilever vibration in order to identify the modal parameters of wind turbine blade.Then,a test platform for large wind turbine blade modal parameter identification was built.The aeroblade 3.6-56.4 wind turbine blade free decay test was finished using rapid unloading device for rapid release of large force.By the damper identification,a law of damping variation was obtained under different initial amplitudes.At the same time,the low-frequency of wind turbine blade was gotten by FFT using the accelerator signals.

Key words: wind turbine blade, attenuation vibration, damping ratio identification, low-frequency identification

摘要：

 为了正确识别大型风机叶片的模态参数,
首先将风机叶片的衰减振动等效为自由悬臂梁振动,推导出阻尼比识别关系式。然后,
构建一个大型风机叶片模态参数识别试验平台,采用快速脱钩装置实现大载荷力的快速
释放,完成对aeroblade3.6-56.4风机叶片的自由衰减试验。根据阻尼比识别关系式,得到不同初始振幅下的阻尼比变化规律。同时对叶片某面的加速度信号进行傅里叶变换,得到其低阶固有频率。

关键词: 风机叶片, 衰减振动, 阻尼比识别, 低阶固有频率识别