Shaking table tests of a 1.5 MW wind turbine model were performed to investigate seismic responses of the wind turbine under ground motions with different spectral characteristics.The wind turbine tower model was carefully designed to satisfy the frequency and mode similarity relations.Blades and infinitely variable motor were installed at the top of wind turbine model to simulate the wind turbine operating conditions.Two suites of ground motions,including long period ground motions and general ground motions with different site soil characteristic periods,along with three classical ground motions,were selected to match the design response spectrum in Chinese standard.Besides,two artificial waves were generated using the trigonometric series superposition method.All ground motions were inputted in three different directions.Acceler-ation and displacement responses both at the tower top and along the tower,and strain responses at the tower bottom were measured and com-pared.The test results showed that the wind turbine responses of principle direction and secondary direction have distinct coupling effects and high mode effects.Wind turbine seismic behaviors were quite different under ground motions with different frequency contents.Long period ground motions can lead to amplification of wind turbine acceleration and displacement responses.Besides,different directions of ground motion inputs in-duced different structural responses.The ground motions with the direction perpendicular to the wind turbine blade plane or with an angle of 45° can lead to amplification of wind turbine responses.%为研究风电塔在不同频谱特性地震动下的响应规律,针对某风电塔设计缩尺模型开展大型振动台试验.对模型塔筒进行精细设计,实现结构自振特性与原型结构相似,同时对试验模型配置叶片和无级变速电机实现运转工况模拟.根据抗震设计规范给出的设计反应谱和特征周期,选择长周期地震动和短周期地震动各2条,以及经典地震动3条,并采用三角级数叠加法生成2条人工地震波,沿塔身3个不同方向进行输入,对塔顶和塔身的加速度和速度响应以及塔底应变响应进行测试,比较风电塔模型在不同地震动和不同输入条件下的响应差异.试验结果表明,风电塔结构主次方向地震响应具有耦合现象,同时表现出高阶振型效应.风电塔在不同频率成分地震动下的响应具有较大差别,长周期地震动对风电塔模型加速度和位移响应具有放大效应.此外,风电塔在不同地震动输入方向下的响应不同,地震动主方向沿叶片平面垂直方向输入和45°方向输入下的响应较大.
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