随机波浪荷载作用下海洋平台的前馈-反馈振动控制研究

该文研究线性前馈 -反馈控制策略对海洋平台振动控制的有效性。线性前馈 -反馈控制只有当输入荷载为白噪声过程时 ,所实施的控制才是最优的 ,因此该文采用一白噪声过程通过滤波器来近似随机波浪力谱 ,并将海洋平台 -主动控制系统的动力学方程转化为符合随机最优控制要求的增广状态空间表达形式。依据设计目标中对安全性以及经济性的权衡 ,通过使二次型控制目标函数最小化 ,推导出了随机最优控制力的计算方法 ,从而实现了最优控制的目的。在频率域上分析了海洋平台受控后的振动响应 ,结合典型的海洋天然气生产平台算例 ,将前馈 -反馈控制与反馈控制、TMD控制加以比较 ,总结了前馈 -反馈控制的特点及其优越性

Study on Feedforward-Feedback Control for Offshore Platforms Under Random Wave Force Excitation

The major objective of this paper is to investigate the effectiveness of feedforward feedback (FF FB) control for offshore platforms under wave loading. Herein, a method of offshore structural control is presented, which employs both feedforward and feedback control compensation . The approach is to augment the equation of appended state space for the platform active control system. In order to satisfy the random optimal control conditions, in this paper an analog filter to approximately represent the wave force spectrum is used. The control law is obtained by minimizing the quadratic performance by using the standard Ricatti solution. In this paper the controlled response of the platform in the frequency domain is reduced. Finally, a numerical example applied to an offshore platform is presented to illustrate the developed design procedure. The results show that the proposed method offers advantage in performance over the control method employing only state feedback or TMD control.