摘要
通过随机振动理论研究了风力机的随机响应及其基准期内反应极值的求解方法。风振反应被分解为均匀风振响应和脉动风振响应两部分进行分析,采用虚拟激励法(PEM)计算了风力机叶片和塔架在脉动风作用下的随机抖振反应,从而计算了随机抖振反应极值的数学期望;根据风剪效应计算了极值均匀风所引起的风振反应。结果分析表明,在频域内计算抖振反应的极值有效避免了在时域内采取多条风速时程样本求取极值的复杂过程,方法更为精确;同时通过采用PEM方法,自动考虑模态耦合影响,且理论上是精确的算法。
The random response of wind turbine and the calculation metliod of extreme wind-induced response in design period were studied by random vibration theory.The wind-induced response was decomposed into a mean wind-induced response component and a fluctuating wind-induced response component.The random buffeting wind-induced responses of blade and tower were calculated by pseudo excitation method(PEM),and accordingly the mathematical expectation of extreme random buffeting responses can be obtained.The extreme mean wind-induced response calculated by wind shear effect.The results show that the extreme buffeting wind-induced responses calculated in frequency domain can effectively avoid complex process that the extreme responses are calculated by multi-samples of wind velocity time series in time domain, and the method is more accurate.Based on the PEM,the modal coupling effect can be included automatically, and it is an accurate algorithm in theory.
引文
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