舰船动力定位系统切换控制器的设计与分析

Design and Analysis of Switching Controller for Ship Dynamic Positioning Systems

为应对不断变化的海洋环境,提高舰船动力定位系统对不确定参数的鲁棒性,基于切换系统理论,设计了切换控制器。建立了舰船数学模型,并分别在4种海况下设计不同的PID控制器和无源观测器,通过引入尺度无关迟滞开关逻辑算法,根据实测海况参数,在不同控制器、观测器之间进行切换,从而选出合适的控制器和观测器。在MATLAB上对一实际舰船模型进行仿真,分别比较切换控制器与实际应用中的最优控制器在变化海况下的性能,结果显示在不断变化的海况下切换控制器仍能有效进行动力定位作业,而最优控制器在恶劣海况下变得不稳定,仿真结果表明所设计切换控制器提高了舰船动力定位系统的鲁棒性。

A switching controller is designed based on switched system theory to deal with continuingly varying sea conditions and to improve robustness of ship dynamic positioning systems to uncertain parameters.By establishing ship models and separately designing different PID controllers and passive observers for four different sea conditions,a controller is designed,which can use scaleindependent hysteresis switching logic to choose the appropriate controller and observer via measured sea parameters.Simulations are conducted on a real ship model with the help of MATLAB,comparing the performances of switching controller and optimal controller which is now equipped on real ships.The results show that even in the severe sea conditions,switching controller can still work well to guarantee the proper functioning of ship dynamic positioning systems in comparison to optimal controller,which demonstrates the robustness of the switching controller.