针对动力定位水面船舶,基于Luenberger观测器构造原理及Lyapunov稳定性理论,构造一个船舶动力定位系统的非线性状态观测器。所设计观测器较卡尔曼滤波器的主要优越性在于不需要对船舶的运动方程进行线性化处理,且具有全局的指数稳定性。最后,用一艘供给船对所设计观测器进行数值仿真研究,仿真结果表明所设计非线性观测器具有良好的滤波及状态估计性能,船舶运动状态估计值指数收敛于其实际值,验证了所设计船舶动力定位系统非线性观测器的有效性。
For surface ships with dynamic position,a nonlinear observer for ship dynamic positioning systems is constructed based on Luenberger observer structural principle and Lyapunov stability theory.Comparing to Kalman filter,the main advantage of the nonlinear observer is that the motion equations of ships need not be linearized and the global exponential stability is guaranteed.Finally,the simulation research is done on a supply ship,which shows that the designed nonlinear observer has good performances of filtering and state estimation.All estimations of ship movement states converge exponentially to their actual values.The effectiveness of the nonlinear observer for dynamic positioning system of ships is verified.