海洋柔性立管输出反馈边界控制

Boundary output feedback control for a flexible marine riser

针对耦合内流动力学的海洋柔性立管系统,为了提高其振动控制品质,结合Lyapunov直接法和高增益观测器理论设计了输出反馈边界控制和干扰观测器,用以抑制结构振动偏移量和减弱外部环境干扰载荷的影响.其后,证明了闭环系统解的存在性、唯一性和收敛性及闭环状态的一致有界性.此外,本文的控制设计和稳定性分析是基于立管的原始无穷维动力学进行的,因此关于模型截断法产生的控制溢出问题将不会产生.最后仿真结果验证了本文所提出的输出反馈边界控制器能有效抑制柔性立管的振动.

For improving the vibration control performance of a marine riser including the dynamics of internal fluid,an output feedback boundary control with disturbance observer is designed to suppress the riser’s vibration displacement and mitigate the effects of the external environment disturbance by integrating Lyapunov’s direct method and high-gain observers.With the proposed output feedback boundary control, the existence, uniqueness and convergence of the solution for the closed-loop riser system and the boundedness of all closed-loop signals are proven. In addition, the control design and stability analysis are carried out on the basis of the original infinite dimensional model without any discretisation or simplification of the dynamics in the time and space, thus the control spillover problem associated with the traditional truncated model-based methods will not arise. In the end, simulation results indicate that the proposed output feedback boundary control can effectively regulate the flexible riser’s vibration despite the existence of system states obtained inaccurately.