【作者】 张薇；

【导师】 赵希人；

【作者基本信息】 哈尔滨工程大学 ， 控制理论与控制工程， 2009， 硕士

【摘要】 自动舵是船舶操纵控制系统中至关重要的设备,是船舶操纵性能好坏的标志。它一直是船舶运动控制领域内的重要研究课题之一,许多专家学者一直在致力于该方向的研究工作。传统的PID自动舵缺乏对船舶动态特性及海况的适应能力,并且依赖于精确的数学模型,而模糊控制不苛求被控对象具有准确的数学模型,对系统模型参数的变化有较强的适应能力,有望解决传统PID控制的弊端。本文的工作就是基于这样的背景开展起来的。早期的控制方法为Bang-Bang控制、PID控制,而后为自适应控制、最优控制、鲁棒控制、非线性控制,到现在研究的智能控制。这些控制方法都应用到船舶航向控制的研究中,并已形成了PID自动舵、自适应自动舵等产品,但由于船舶运动的复杂性,船舶的动态特性具有大惯性、大时滞、非线性等特点,航速及装载变化产生了模型的参数摄动;航行中海风对船舶动态产生偏置力和附加动力、海流产生船位的漂移、海浪造成船舷向角的附加高频振动和低频漂移,以及航行条件的变化、环境参数的严重干扰和测量的不精确性等都使船舶动态产生不确定性,而传统的自适应控制等控制方法无法有效控制未建模动态系统,从而影响了自适应舵的控制效果。为了解决上述问题,需要进一步将智能控制技术引入自动舵的技术中,研究混合型的智能自动舵,本文采用了将PID与模糊控制相结合的方法,以适应船舶运动控制的要求。首先对船舶操纵控制技术和智能自适应控制技术发展现状以及PID控制器参数整定方法的概况进行了综述。在分析了船舶操纵运动的动力学方程的基础上,建立了船舶航向控制的线性和非线性数学模型以及风、浪、流的干扰模型。简单介绍了船舶航向控制的基本原理,同时研究传统的PID自动舵的数学模型及设计过程。在分析了传统自动舵控制缺陷的基础上,为使船舶能在不同状态和环境下按所希望的要求改变船舶航向,提出了一种基于模糊控制的自适应算法。首先讨论了模糊控制的基本思想和基本理论,在此基础上分析了船舶航向控制这种特殊的被控对象的特性,从而提出了船舶航向的模糊控制技术,设计了船舶航向模糊控制系统,这也是进一步设计其它高性能模糊控制器的基础。这种控制器易于设计、实现方便,较传统PID控制有更快的响应速度和更小的超调,但其存在静态误差;为了进一步提高模糊控制器的控制特性,在此基础上分别设计了模糊PID控制器。利用模糊集合理论在线自调整PID参数,结合模糊控制和PID控制各自的优点,从而提高了系统的自适应能力和实现了无差控制。本文最后给出了控制器的仿真曲线,仿真结果表明所设计的控制器达到了预期的控制效果。更多还原

【Abstract】 The autopilots have played a very important role in ship maneuvering systems,which is the symbol of the property of ship steering. It has been one of the most important research topics of ship’s maneuvering system,so a lot of experts and scholars have worked hard on it. But the conventional PID autopilot systems are lack of adapting to the ship dynamic property and the changes of sea environment, and they need to build up the mathematical model of ship. On the contrary,fuzzy control don’t depend on the mathematical model of controlled objects and have the ability to adapt to the changes of system parameters, so it has the potential to overcome the drawbacks of conventional control schemes. The paper is developed under such engineering background.Control method for the early Bang-Bang control,PID control, and then for the adaptive control,optimal control,robust control, nonlinear control,up to now the study of intelligent control. These control methods are applied to the ship course control study, and has formed a PID autopilot,adaptive autopilot and other products,but because of the complexity of ship maneuvering, and that the dynamic characteristics of the ship features of a large inertia, large time-delay, and non-linear, the change of speed and load causes the model parameter perturbation; because of the additional power dynamically caused by the wind,drift of the ship’s position caused by the current, the additional high-frequency vibration and low-frequency drift of the angle caused by the waves,the changes of conditions,the interference of environmental parameters and the non-precision of measurements, the ship dynamically has uncertainties in the voyage. And traditional control methods can not effectively control the unmodeled dynamic system, thus the effect of the autopilot control is declined. In order to solve the above problems, the further introduction of intelligent control techniques in autopilot technology is necessary. This article uses the combining of PID and fuzzy control method,in order to adapt to the requirements of ship motion control. First of all,the development of ship control technology and intelligent self-adaptive control technology and the tuning method of PID controller parameters are reviewed. In this paper,ship’s mathematical model is researched,in consideration of,the forsces and moments from the environmental disturbances, such as winds, waves, currents, etc. According to nonlinear, time-varying and time-delayed parameters of ship course,the fuzzy controller was first designed based on the analysis of the fuzzy control theory, which is the basis of other high-level controllers. This kind of controller is easy to design and operate,and has improved convergence rates and less over shoot than PID controller,but has stable error. In order to improve the properties of the fuzzy controllers,a fuzzy-PID controller was designed respectively based on the fuzzy controller. The PID parameters on-line by using fuzzy set theory to improve the self-adaptive ability and to realize non-error control.At last,the simulation curve was given,and which show that the desired results were attained.更多还原