船舶动力定位系统的精细抗干扰控制

Elegant anti-disturbance control for dynamic positioning system of ships

船舶在航行过程中不可避免地受到海平面上多种干扰的影响.动力定位(DP)是一种船舶在受到外界干扰的情形下依然能够保持在一定位置或沿固定轨迹航行的技术.与传统的锚定位方法相比, DP技术具有机动性强、可深海作业、定位精度高等优点.针对带有慢变环境干扰和复杂非线性项的船舶动力定位系统,研究其精细抗干扰控制问题.首先,利用模糊逻辑系统逼近船舶动力定位系统中的复杂非线性项.其次,通过构造自适应干扰观测器(ADO)来估计部分信息已知的慢变环境干扰.在此基础上,将基于干扰观测的控制(DOBC)与模糊控制算法相结合,提出基于复合分层抗干扰控制框架的精细抗干扰控制(EADC)策略,从而实现船舶动力定位系统的高精度抗干扰控制.最后,基于供给船模型的仿真研究验证所提控制策略的有效性.

In the process of navigation, ships are inevitably affected by various disturbances on the sea level. Dynamic positioning(DP) refers to a technology that ships can still maintain a certain position or navigate along a fixed track under the existence of external disturbances. Compared with the traditional anchor positioning method, DP technology has the advantages of strong mobility, deep-sea operation and high positioning accuracy. The anti-disturbance control problem of dynamic positioning system of ships with slowly varying environmental disturbances and complex nonlinear term is investigated in this paper. Firstly, the fuzzy logic system is used to approximate the complex nonlinear term in the dynamic positioning system of ships. Secondly, to estimate the slowly varying environmental disturbances with partially-known information, an adaptive disturbance observer(ADO) is constructed. Based on this, an elegant antidisturbance control(EADC) strategy is proposed by integrating disturbance observer based control(DOBC) and fuzzy control algorithm to achieve high accuracy anti-disturbance control. Finally, the simulation results on supply ship model are presented to demonstrate the effectiveness of the proposed strategy.