为研究风力机结构设计载荷需求与抗震强度之间的关系，通过Wolf方法考虑土-构耦合效应，并基于开源软件FAST建立通用的风力机地震工况动力学仿真模型。以AOC 50 kW、WindPACT 1.5 MW和NREL 5 MW三台不同功率的风力机为研究对象，计算101种不同强度地震与湍流风联合作用下，三台风力机在不同运行方式下的结构动力学响应。结果表明：地震载荷加剧了风力机塔顶振动，在加速度峰值为2.14 m/s2的地震作用下，NREL 5 MW风力机机舱加速度波动范围增大4.7倍。由此诱发紧急停机，叶片顺桨过程中使得气动阻尼急剧降低，从而导致结构载荷发生增幅振荡，说明地震发生时，紧急停机操作并不能有效降低塔顶振动。在高强度地震工况下，塔基弯矩最大响应值与设计地震加速度峰值之间为线性关系。提出了一种新的塔基结构强度设计需求预估模型，在不同强度地震范围均有较高的拟合度，可为抗震型风力机结构载荷设计提供较高的参考价值。
In order to analyse the relation between structural strength loading demands of wind turbines and design earthquake intensity,a universal seismic analysis framework has been developed based the open source tool FAST with taking into account the soil structural interaction effect using Wolf method.Three distinct wind turbines (AOC 50 kW,WindPACT 1.5 MW and NREL 5 MW) have been selected as the research objects.The structural dynamic responses of the wind turbines operating in different modes under multiple loadings combined by 101 earthquake excitations and turbulent wind are obtained.The results indicate that earthquake excitation increases the vibration amplitude of tower-top significantly.The fluctuation range of nacelle acceleration of NREL 5MW has been widened around 4.7 times under the influence of an earthquake event with a peak of ground acceleration of 2.14 m/s2.Emergency shutdown is induced.The aerodynamic damping of the rotor decreases rapidly due to pitching to feather resulting in more severe vibration with a larger amplitude.It indicates that the emergency shutdown cannot mitigate the vibration on tower-top of the wind turbine subjected to an earthquake event.The maximum tower-base moment demand increase linearly with the peak of target earthquake acceleration.A novel model of pseudo-spectral acceleration and tower-base moment demand is developed for better estimations of seismic loading demands.The proposed model can estimate the tower-base moment demands more efficiently for the different wind turbines subjected to different earthquakes compared to present models.The findings can be referred for structural design of aseismatic wind turbines.
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