【作者】 王立军；

【导师】 张显库；

【作者基本信息】 大连海事大学 ， 交通信息工程及控制， 2013， 博士

【摘要】 船舶减摇控制是船舶运动控制领域的一个重要研究方向,其中舵减摇控制系统是在传统航向自动舵基础上发展起来的一种特殊减摇装置,它能在确保航向保持控制满足性能要求的情况下取得较好的减摇率,并克服了减摇鳍的缺点,从而提高了舰船在恶劣海况条件下的适航性、安全性以及乘员舒适性。本文针对船舶减摇航迹保持控制系统进行了较为深入的研究,首先分析了船舶的欠驱动性和横摇对舵响应运动的非最小相位性,并进一步对船舶在大幅度动舵时首摇和横摇的耦合机制进行了定性分析和定量仿真研究,数值仿真试验结果显示在大舵角转向时,船舶的首摇和横摇运动存在较强的耦合作用,横摇幅度和首摇幅度存在较强的正相关性。在分析船舶首摇和横摇耦合机制的基础上,为了建立更加准确的响应型船舶运动模型,综合考虑横摇对舵响应运动的非最小相位性、振荡性和惯性横倾,提出一种横摇响应运动模型,其参数具有典型的物理意义且估值简单。在此基础上,以某海军多功能运输船的非线性运动模型的对舵响应输出为样本数据,应用一种自适应遗传算法对响应型船舶运动模型参数进行辨识,得到该船的首摇与横摇响应模型,仿真对比试验结果显示所得响应模型能够以较高的精度逼近样本数据,验证了响应型船舶运动模型及其参数辨识方法的有效性和可靠性。闭环增益成形算法以鲁棒控制理论作为理论基础,利用了混合灵敏度算法的结果,是一种简捷鲁棒控制算法。为了更好地满足船舶转向和航向保持对舵机设备的不同控制要求,基于一阶闭环增益成形对船舶转向操纵过程分3段进行设计航向控制器,按照每个阶段的典型特征设计对应的模糊隶属度函数,然后对3个控制器的输出进行T-S模糊综合。以某海军多功能运输船的非线性模型为控制对象,考虑了平均风和脉动风干扰后进行了仿真模拟试验。结果显示控制系统具有超调幅度小、响应速度快的动态控制特性,以及较好的航向保持性能。基于船舶横摇运动对波浪干扰的响应具有高频带通特性,在经典闭环增益成形算法的基础上提出一种频带干扰抑制控制算法,其控制器设计具有过程简单、参数物理意义明显以及频域解耦的特点。针对船舶横摇运动的非最小相位特性,采用其镜像映射设计非稳定过程的控制器。以某海军运输船的非线性数学模型为受控对象,分别设计了舵减摇控制器和航向保持控制器。考虑不同遭遇周期的海浪干扰并进行了仿真试验。结果显示该控制系统在船舶横摇自然频率附近频带内减摇效果显著,并具有良好转向和航向保持性能。为了消除舵机中存在的间隙非线性给船舶航向保持带来的不良影响,采用一阶和二阶闭环增益成形算法混合控制策略,充分发挥二阶算法的动态控制性能良好和一阶算法能消除静差的优势。以某海军运输船的非线性数学模型为控制对象进行了仿真实验,结果显示在恶劣海况下,控制器能够消除舵机间隙非线性带来的不良影响,混合控制策略能降低航向超调量且具有良好的鲁棒性能。为进一步实现鲁棒航向保持控制器的参数自适应调整和优化,将基于闭环增益成形算法的二阶航向保持控制器参数分成模型参数和干扰带宽参数两部分。针对由于航速等变化引起的模型参数摄动,提出在利用遗传算法实现响应型船舶运动模型参数在线辨识的前提下对控制器模型参数进行适应性调整,同时针对海况变化引起航向保持性能的下降,以航向保持误差最小和舵机损耗最小作为适应度函数优化干扰带宽参数,从而实现控制器模型参数的适应性调整与干扰带宽参数的在线优化。仿真结果表明,与固定参数控制器相比该控制系统具有更高的航向保持精度、较小的航向调节时间和超调幅度。该系统对于模型摄动和外界干扰具有较好的适应能力,具有明显的工程应用意义。针对减摇航迹保持控制中存在的多目标优化问题,应用非支配排序遗传算法提出了舵减摇与航迹保持控制的鲁棒协同优化方法。本研究首先在非线性船舶运动模型线性化的基础上提出了一种响应型简化线性模型,然后基于闭环增益成形算法建立了航迹保持与舵减摇的简捷鲁棒控制器,进而针对航迹跟踪精度、舵减摇率和舵机能耗3个目标函数,利用NSGA-II实现了控制系统参数的鲁棒协同优化。最后对某海军运输船的非线性模型进行了仿真试验,结果显示Pareto优化解集能充分反映多目标函数之间的制约性,性能最优解参数方案与经验参数方案相比能够实现更好的航迹跟踪精度和减摇效果。更多还原

【Abstract】 Ship roll stabilization is a very important research trend in ship motion control field. Rudder roll stabilization (RRS) is a new ship roll stabilization device based on the traditional course autopilot system. The autopilot with RRS can achieve good roll reduction rate and satisfactory course-keeping performance, and overcome the disadvantages of stabilizing fins, and then improve the ship’s seaworthiness, navigational safety and personnel comfort in rough sea conditions.The thesis has made an intensive study of track keeping autopilot with RRS. Firstly, analysis is done on the underactuation of ship motion and the non-minimum phase characteristic of roll responding, and the coupling mechanism between yaw and roll in case of big amplitude rudder is determinated qualitatively and quantitatively by simulations. The results indicate that the coupling mechanism between yaw and roll is obvious, and the amplitudes of yaw and roll have strong positive correlation property.Based on above analysis, to establish a more precise ship responding motion model, a roll responding model is brought up based on the full consideration of non-minimum phase, damped oscillation and inertial heeling of the roll responding to rudder motion. The model parameters have obvious physical meanings, which can be estimated simply according to the responding curve. The rudder responding outputs of a nonlinear multifunctional naval vessel model are set as the test data. The parameters of the ship responding motion model are identified by adaptive GA algorithm, and then the yaw and roll responding models are constructed. Simulation tests results indicate that the ship responding motion model can approach the test data with little error, which verifies the validity and reliability of the ship responding motion modeling.The closed-loop gain shaping algorithm is a simplified H∞robust control theory, which constructs the controller using four parameters with obvious engineering significance. To satisfy the different requirements of course-changing and course-keeping, a fuzzy ship steering control system is developed according to three turning stages based on closed-loop gain shaping algorithm. Three subsystems are integrated by T-S fuzzy model, whose fuzzy membership functions are designed for each controller in accordance with the features of three turning stages. The proposed methodology is verified by simulation tests on nonlinear model of a multifunctional navy ship considering wind disturbances. Simulation results indicate that the system has swifter responding, less overshoot and better course-keeping performance.Considering the frequency-domain characteristic of ship roll motion response to wave disturbance is high and band-pass, a new band interference suppression method is proposed based on the closed loop gain shaping algorithm. The controllers designed by proposed method are concise and decoupling with several obvious physical significance parameters. Because the ship roll motion is an unstable non-minimum phase system, a mirror-injection method is used to design controller. Both the RRS controller and course-keeping controller are designed on a nonlinear naval ship model. Simulation tests are done in the condition of wave disturbance with different periods. The results show the controllers achieve good disturbance rejection in the ship’s natural roll frequency band, and stable performance of course keeping and changing.In order to eliminate the blight of the backlash nonlinearity in the rudder servo system to course-keeping for ships, the hybrid control strategy of the first and second order closed-loop gain shaping algorithms is used to make the best of its fine dynamic performance of the second order closed-loop gain shaping algorithm and the static error banishing of the first order closed-loop gain shaping algorithm. The simulation experiments are carried out on a nonlinear naval ship model. The simulation results show that the controller can eliminate the blight of the backlash nonlinearity under heavy sea state and reduce the peak overshoot with satisfactory robustness.In order to solve the uncertainty in ship motion control and optimize the robust course controllers, the parameters of a second order course controller based on closed-loop gain shaping algorithm is divided into model parameters and the disturbance bandwidth parameter. For the ship model perturbation, the parameters are adaptively adjusted when the responding ship model is identified online by genetic algorithm. Moreover, the bandwidth parameter is optimized to the minimize course keeping error and steering gear consumption under the influence of the sea state. The simulation tests indicate that the control system achieves higher course keeping precision, shorter setting time, smaller overshoot and better adaptivity to model perturbation and disturbance, which shows obvious significance of engineering.A concise robust collaborative optimization control system of track-keeping autopilot with RRS is brought up to solve the multi-objective optimization problem in it. Firstly, the linear responding equivalent model is advanced to replace the nonlinear ship model in controller design. The track-keeping and RRD controllers are designed based on closed loop gain shaping algorithm, and the parameters of above controller are collaboratively optimized by fast and elitist non-dominated sorting genetic algorithm (NSGA-II) with3objectives, such as the track-keeping accuracy, rudder roll reduction rate and the energy consumption of steering gear. Finally, simulation tests are done on non-linear model of a naval carrier. The results indicate that the Pareto optimal set can represent the conditionality among the objectives. And the simulations based on the optimum solution achieve better track-keeping accuracy and roll reduction rate than empirical parameters.更多还原