基于高增益观测器的船舶动力定位系统的输出反馈控制

Output feedback control for dynamic positioning system of a ship based on a high gain observer

针对动力定位船舶的速度向量不可测的问题,考虑外部环境扰动,将高增益观测器、动态面控制技术和矢量backstepping方法相结合,设计仅依赖于船舶位置和艏摇角测量值的船舶动力定位系统输出反馈控制律.动态面控制技术的引入,使控制律结构简单,易于工程实现.应用Lyapunov函数证明了所设计的控制律能迫使船舶的位置和艏摇角收敛于期望值,并保证船舶动力定位输出反馈闭环系统所有信号均一致最终有界.基于一艘供给船的仿真研究验证了所设计的基于高增益观测器的船舶动力定位输出反馈控制律的有效性.

Because the velocity vector of the ship is not available, we propose output feedback control for dynamic positioning system of a ship with external disturbances by integrating the high gain observer, the dynamic surface control technique and the vectorial backstepping design. The proposed control scheme only relies on measurements of the ship position and heading. Because of the introduction of the dynamic surface control, the designed control law is simpler and more easily to be implemented in engineering practice. It is proved by means of Lyapunov function that the proposed control law can force the position and heading of the ship to approach the desired values while guaranteeing the uniform ultimate boundedness for all signals of the closed-loop dynamic positioning system. The simulation results on a supply ship are presented to demonstrate the effectiveness of the proposed strategy.