基于反步控制的半潜平台动力定位数值计算研究

装配动力定位系统的浮式结构物由于受到风、浪、流等交变载荷影响，其运动具有明显时滞和非线性特性，为克服传统控制策略抗干扰能力差对动力定位控制性能的影响，文章基于反步法，对动力定位系统进行了控制器设计研究，针对波浪及流外载荷形成的有界干扰问题，采用自适应策略进行估计补偿。并借助Lyapunov理论分析了闭环系统的稳定性。最后以某深水半潜平台为对象，对其不同工况下动力定位作业进行了数值计算研究，验证了所设计控制器具有良好的鲁棒性，可为后续动力定位模型试验及实船控制器设计提供理论支撑。

Numerical Evaluation on Dynamic Positioning for Semisubmersible Platform based on Backstepping Control

The positioned floating structures are continuously exposed to environmental disturbances of wind, waves and current. So the motions have obviously delay, large inertia and nonlinear charac-teristics. In order to overcome these problems, a backstepping control algorithm is presented. This controller is robust to variations in environmental and loading conditions by incorporating adaptive strategy to compensate environmental disturbances. The stability of designed controller is proved by using the Lyapunov theory. The performance of the controller is validated by numerical simulations of a semisubmersible platform with azimuth thrusters in operation and survival conditions. The simula-tion results indicate that the designed controller is very efficient and satisfactory performance of sta-tion and heading keeping is observed. The studied work can provide technique support for practical applications in full-scale and model tests of floating structures.