船舶航向非线性系统的多滑模自适应模糊控制

针对参数未知的船舶航向非线性控制系统数学模型,在考虑舵机伺服机构特性的情况下,船舶航向控制问题就成为一个虚拟控制系数未知的非匹配不确定非线性控制问题.基于多滑模设计方法和模糊逻辑系统的逼近能力,提出了一种多滑模自适应模糊控制算法,通过引入非连续投影算法和积分型Lyapunov函数,提高了系统在抑制参数漂移、控制器奇异等方面的能力.借助Lyapunov函数证明了所设计控制器使最终的闭环非匹配不确定船舶运动非线性系统中的所有信号有界,且跟踪误差收敛到零.仿真研究表明:该算法与传统的PID控制相比,具有较好的跟踪能力和自适应能力.     

基于参考模型的电力推进船舶航向滑模控制器设计

针对全回转舵浆的电力推进船舶航向控制问题,基于等价舵效建立的船舶回转运动响应方程,设计了基于参考模型的滑模控制器。该控制器含有两个滑模控制子系统,其一用来控制参考模型,以获得理想的动态响应;另一个以前者每个控制周期对应的状态为控制目标输入,引导船舶航向收敛于设定值。仿真结果表明,在满足全回转舵浆回转角幅值与速度的限制下,该方法能够有效解决滑模控制输入的强抖振问题,能降低滑模控制输入的要求,且具有良好的鲁棒性与控制效果。     

基于改进型积分终端滑模控制方法的移动机器人轨迹跟踪设计与实验

为了使移动机器人获得高精度和快速收敛的跟踪性能,设计一种基于积分终端滑模和滑模观测器的轨迹跟踪控制方法.首先,考虑到移动机器人在实际运动过程中会受到地面湿滑、摩擦等原因引起的侧滑扰动的影响,建立其在该扰动影响下的运动学模型;然后,利用该动态模型设计滑模观测器来估计系统受到的扰动;接着,将估计的扰动值前馈至反馈控制器,用来抑制扰动对系统控制性能的影响,从而达到削弱抖振的目的;同时,基于跟踪误差设计积分终端滑模面,并结合滑模面和扰动估计设计新型积分终端滑模控制器;最后,基于Lyapunov稳定性理论对整个闭环系统进行稳定性分析.仿真实验结果表明,所设计的控制器具有更高的跟踪精度和更强的鲁棒性.     

基于自适应模糊滑模控制的分数阶混沌系统的投影同步

基于模糊控制理论和滑模控制理论以及自适应控制理论,研究了一类含有外部扰动的不确定分数阶混沌系统的混合投影同步问题.提出了一种自适应模糊滑模控制的分数阶混沌系统投影同步方法.模糊逻辑系统用来逼近未知的非线性函数和外部扰动,并且对逼近误差采用了自适应控制,同时构造了一种具有较强鲁棒性的分数阶积分滑模面.应用分数阶Barbalat引理设计了自适应模糊滑模控制器和参数自适应律.最后数值仿真结果验证了所提控制方法的有效性.     

基于自适应滑模的喷水推进船舶航向控制

关于船舶航行优化控制,针对喷水推进船舶的航向稳定性控制问题,根据模型中非线性水动力不确定性和外界干扰,提出了基于PID增益调节的自适应滑模控制方法, 并利用Lyapunov稳定性理论证明控制方法的稳定性.控制方法对于模型参数摄动和外界干扰有较好的鲁棒性,PID增益参数的选择可通过在线自适应学习获得,采用边界层方法对设计的滑模控制器的高频抖振加以合理抑制.以一艘喷水推进船舶为例,进行了航向改变的仿真,结果表明设计的控制器具有船舶操纵的良好动态性能,且具有超调小、鲁棒性强的优点,更加符合船舶航向实时控制的工程要求.     

舰载机自动着舰纵向控制系统设计

航空母舰在大海上以一定速度作匀速直线运动时,海浪激励舰体作三自由度摆动运动,同时伴有低空大气紊流和舰尾流的干扰,使得舰载机着舰的环境十分恶劣,这样对自动着舰控制系统提出了极大的挑战.针对这一特殊问题,本文提出一种指令滤波积分反步滑模控制方法,首先该方法采用指令滤波处理反步的计算膨胀问题,然后引入滑模控制来解决外界扰动和匹配不确定性问题.考虑到降低滑模控制引起的抖动,本文利用高阶滑模控制的思想,在传统的反步方法上增加了一个附加虚拟控制状态方程,将控制器的最终输出作用在一个积分器上,这样不仅可以降低滑模控制的抖动,还可以利用反步方法处理不匹配不确定性问题.最后在理论上证明了所提出方法的全局稳定性,并通过仿真实验验证了该方法的有效性.     

非线性非最小相位船舶舵减摇系统的滑模控制

建立了从舵到横摇角的非最小相位非线性船舶模型,利用滑模控制方法设计同步横摇阻尼和航向保持的稳定控制器。船舶减摇建模时假设模型误差的数量级和扰动已知,且设计的滑模控制器可实现对一阶波浪扰动的稳定调节。基于李亚普诺夫稳定性理论证明了整个闭环系统的稳定性,仿真实验的结果验证了所设计的控制器的优良跟踪性能和鲁棒性。     

基于NDOB的匹配/非匹配不确定性系统滑模控制

针对一类n阶匹配与非匹配不确定性和扰动共存的系统,提出了一种新颖的基于非线性干扰观测器的滑模控制方法。将非匹配扰动的估计值融入到滑模面,设计了集成扰动观测的滑模控制。与传统的滑模控制方法相比,该方法在匹配与非匹配不确定性和扰动出现时具有较好的抑制能力,并能有效地抑制切换增益所引起的抖振现象。利用李雅普诺夫理论和输入-输出稳定性概念严格证明了闭环系统的稳定性。最后通过两个仿真实例验证了所提控制方法的有效性。     

基于反演自适应动态滑模的气垫船航向控制

针对全垫升气垫船运动非线性明显、可操纵性差,为改善操控水平,能够准确地按给定航向航行,设计了反演自适应动态滑模的航向控制算法。建立了三自由度全垫升气垫船平面运动数学模型,并给出了航向非线性控制模型。将反演方法与动态滑模相结合,设计新型切换函数,以实现航向的平滑、无抖振控制。最后,在不同外界扰动作用下进行了仿真,试验结果表明,所设计航向控制算法能够提高全垫升气垫船航向的控制精度,具有自适应性强、响应速度快、稳定性好等特点。     

非匹配不确定系统的终端滑模分解控制

针对非匹配多变量模型不确定系统,提出了一种终端滑模分解控制方法.通过状态变换和去耦合处理将系统转换为块能控标准型,它由匹配扰动的值域空间子系统和稳定的非匹配扰动的零动态子系统组成.提出了特殊的终端滑模超曲面,采用滑模控制策略,使值域空间子系统的状态在有限时间内收敛至平衡点,随后非匹配扰动的零动态子系统渐近收敛至平衡点附近的邻域内,且建立了该邻域的范围与系统的非匹配不确定性范围之间的数学关系,并用于系统的设计与分析.所提方法对于维数较高的非匹配不确定系统的控制具有较大的意义,可简化设计,实现递阶控制.仿真实     

AN ASYMPTOTIC SECOND‐ORDER SMOOTH SLIDING MODE CONTROL

Presented is a method of smooth sliding mode control design to provide for an asymptotic second‐order sliding mode on the selected sliding surface. The control law is a nonlinear dynamic feedback that in absence of unknown disturbances provides for an asymptotic second‐order sliding mode. Application of the second‐order disturbance observer in a combination with the proposed continuous control law practically gives the second‐order sliding accuracy in presence of unknown disturbances and discrete‐time control update. The piecewise constant control feedback is “smooth” in the sense that its derivative numerically taken at sampling rate does not contain high frequency components. A numerical example is presented.     

用于永磁同步电机的一种非奇异高阶终端滑模观测器

本文提出一种高阶非奇异终端滑模观测器,用来估计永磁同步电机控制系统的转子位置和转速．采用高阶非奇异终端滑模观测器,使得控制系统不必外加低通滤波器,就可获得平滑的反电动势估计值,进而,根据反电动势方程,求解出转子位置和转速．和传统滑模观测器相比,高阶非奇异终端滑模观测器避免了反电动势估计值的相位滞后,提高了转子位置和转速的观测精度．仿真结果表明,高阶非奇异终端滑模观测器具有快速收敛性及更高的跟踪精度,同时消除了系统的抖振．     

An output feedback sliding mode control strategy for MIMO systems of arbitrary relative degree

This paper develops an output feedback sliding mode controller for multi‐input multi‐output (MIMO) systems of any relative degree. A minimal set of outputs and output derivatives are identified to determine an augmented system which is relative degree 1, and a robust sliding mode differentiator is presented as the means to construct the extended output signal. It is shown that the transmission zeroes of the original plant appear directly in the reduced order sliding mode dynamics relating to the augmented system. A super twisting control algorithm is shown to provide robust control performance. Simulation results for a rationalized helicopter model taken from the literature are used to demonstrate the attraction of the approach. Copyright © 2010 John Wiley & Sons, Ltd.     

基于滑模产生条件的模糊滑模控制及其稳定性分析

通过将表示滑模运动特征的代数值作为模糊系 统的一维输入，本文简化了模糊滑模控制的系统 结构，从根本上消除了规则的组合爆炸， 并针对一类特定系统进行了稳定性分析．PM同步电机位置伺 服控制的仿真表明了这种控制 算法的有效性和简便性．     

永磁同步电动机混沌系统光滑二阶滑模控制

提出基于二阶滑模的控制方法控制永磁同步电动机（PMSM）中的混沌现象。利用Lyapunov函数构造了一种新的滑模面,能保证在滑模面上系统状态在有限时间内稳定到原点。控制器的设计采用了光滑二阶滑模方法,控制输入为光滑的函数,能有效消除抖振现象。仿真的结果也验证了控制方法的有效性。     

An adaptive solution for robust control based on integral high‐order sliding mode concept

A new high‐order sliding mode controller is proposed. The main features are gain adaptivity and the use of integral sliding mode concept. The gain adaptation allows a reduction of the chattering and gives a solution to control uncertain nonlinear systems whose the uncertainties/perturbations have unknown bounds. The concept of real high‐order sliding mode detector is introduced given that it plays a key role in the adaptation law of the gain. This new control approach is applied by simulation to an academic example to evaluate its efficiency. Copyright © 2014 John Wiley & Sons, Ltd.     

SLIDING MODE OUTPUT TRACKING WITH APPLICATION TO A MULTIVARIABLE HIGH TEMPERATURE FURNACE PROBLEM

The paper describes a theoretical framework for the design of a robust multivariable output tracking controller using sliding mode concepts. The approach assumes that only measured outputs are available and uses a sliding mode observer to reconstruct estimates of the internal system states for use in a full information sliding mode control law. This scheme is applied to a control problem associated with high temperature furnaces. The paper describes the synthesis of the proposed control scheme from design through to implementation on an industrial test facility. © 1997 by John Wiley & Sons, Ltd.     

Robust Wind Speed Estimation and Control of Variable Speed Wind Turbines

In this work, a robust control scheme for variable speed wind turbine system that incorporates a doubly feed induction generator is described. The sliding mode controller is designed in order to track the optimum wind turbine speed value that produces the maximum power extraction for different wind speed values. A robust sliding mode observer for the aerodynamic torque is also proposed in order to avoid the wind speed sensors in the control scheme. The controller uses the estimated aerodynamic torque in order to calculate the reference value for the wind turbine speed. Another sliding mode control is also proposed in order to maintain the dc‐link voltage constant regardless of the direction of the rotor power flow. The stability analysis of the proposed controller under disturbances and parameter uncertainties is provided using the Lyapunov stability theory. Finally, the simulation results show that the proposed control scheme provides a high‐performance turbine speed control, in order to obtain the maximum wind power generation, and a high‐performance dc‐link regulation in the presence of system uncertainties.     

Adaptive sliding mode controller based on super-twist observer for tethered satellite system

ABSTRACT

In this work, the sliding mode control based on the super-twist observer is presented. The parameters of the controller as well as the observer are admitted to be time-varying and depending on available current measurements. In view of that, the considered controller is referred to as an adaptive one. It is shown that the deviations of the generated state estimates from real state values together with a distance of the closed-loop system trajectories to a desired sliding surface reach a μ-zone around the origin in finite time. The application of the suggested controller is illustrated for the orientation of a tethered satellite system in a required position.     

A novel dynamic terminal sliding mode control of uncertain nonlinear systems

A new dynamic terminal sliding mode control (DTSMC) technique is proposed for a class of single-input and single-output (SISO) uncertain nonlinear systems. The dynamic terminal sliding mode controller is formulated based on Lyapunov theory such that the existence of the sliding phase of the closed-loop control system can be guaranteed, chattering phenomenon caused by the switching control action can be eliminated, and high precision performance is realized. Moreover, by designing terminal equation, the output tracking error converges to zero in finite time, the reaching phase of DSMC is eliminated and global robustness is obtained. The simulation results for an inverted pendulum are given to demonstrate the properties of the proposed method.