地震载荷对15MW海上风力机动态响应的影响

Effects of Seismic Load on Dynamic Response of a 15 MW Offshore Wind Turbine

为研究地震载荷对15 MW海上风力机动态响应的影响,基于模态加速度法计算了15 MW海上风力机在风-浪-震耦合工况下的支撑结构载荷、塔顶加速度和气动性能,并与无地震工况下的计算结果进行比较。结果表明:地震载荷对侧向剪切力和横摇弯矩影响显著,而纵向剪切力及俯仰弯矩主要受到湍流风作用;地震发生后塔顶最大加速度增幅可达441%,风轮气动推力和扭矩均发生大幅振荡,发电机功率在短时间内波动剧烈程度增大一倍左右;在风电并网的相关研究中,应当考虑由地震载荷引起的短时功率波动对电网的冲击作用。

In order to study the effects of seismic load on dynamic responses of a 15 MW offshore wind turbine(OWT),the support structure load,tower-top acceleration and aerodynamic performance of the OWT under wind-wave-earthquake coupling condition were calculated based on moda-acceleration method,which were compared with those without earthquake.Results show that the lateral shear force and roll bending moment are significantly affected by seismic load,while the longitudinal shear force and pitch bending moment are mainly affected by turbulent wind.Due to the earthquake excitation,the maximum tower-top acceleration can be increased by 441%,both the aerodynamic thrust and torque of the wind turbine oscillate greatly.Consequently,the standard deviation of the generator power increases by around 100%.It is suggested that the impact of short-term power fluctuation caused by seismic load on the power grid should be considered in the related research of wind power integration.