为了保证风力发电机组的安全运行,针对离岸风机导管架式基座在服役过程中受到恶劣海洋环境的影响易产生损伤的问题,提出了一种通过单点响应测量以监测离岸风机导管架式基座健康状态的方法。基于线性莫里森方程和随机波浪理论,建立了随机波浪载荷模型,并通过耿贝尔(Gumbel)概率分布来预测极值波浪载荷的波高。以5 MW离岸风力发电机基座为算例,建立了完好的和损伤的离岸风力发电机基座的有限元模型,计算了离岸风机基座在极值随机波浪载荷作用下的动态响应。通过对动态响应信号的频域分析,获得了风机基座前3阶的固有频率,对完好和损伤两种状态下的离岸风机基座的动态响应的频率变化作了对比分析,得出了损伤对动态响应的影响规律。研究结果表明,通过该方法可以对基座健康状况进行分析,为离岸风机基座健康监测提供了一种可行的参考方案。
In order to ensure the safety of wind turbine,aiming at the problem that jacket-type offshore wind turbine foundation was easy to generate damage because of the harsh marine environment when it was in the process of service, a technique for monitoring the health status of jacket-type offshore wind turbine foundation by single point measurement was proposed. Based on the linear Morison equation and random wave theory, the random wave load model was built. By using the Gumbel probability distribution, the wave height of the extreme wave load was predicted. A finite element model for the foundation of 5 MW offshore wind turbine was established. The dynamic responses of the dam-aged and intact offshore wind turbine foundation excited by the random wave load were computed. The first three order natural frequencies of the turbine foundation could be obtained by applying the fast fourier transform to the dynamic response data. The difference of natural fre-quencies of intact and damaged offshore wind turbine foundations were compared; also, the effects of damage on dynamic response was a-chieved. The results indicate that this method can analyze the health condition of the foundation and provides a feasible reference plan to mo-nitor the health status of offshore wind turbine foundation.