混沌系统的RBF神经网络非线性补偿控制

设计RBF神经网络非线性补偿控制器,提出了混沌系统线性状态反馈的复合控制方法,将可调系统混沌行为镇定到期望目标位置或者变成周期运动.用Lorenz方程作仿真实验,结果证明了该方法的有效性.     

非线性微分——代数系统的输出反馈镇定控制

对满足线性增长条件的非线性微分--代数系统, 研究了其输出反馈镇定控制问题. 通过将状态观测器与控制器耦合在一起设计, 构造出一种非初始化的线性高增益状态观测器, 具有良好的鲁棒性. 基于反推设计方法构造出一个线性的动态输出补偿器, 使得整个闭环系统是渐近稳定的. 仿真结果验证了本文所提控制方法的有效性.     

基于反馈线性化的MIMO非最小相位系统指数镇定

针对仿射多输入多输出非线性非最小相位系统,提出了一种新的镇定方案.用反馈线性化解耦系统输入输出关系,通过高增益状态反馈镇定系统外部动态,用模型预测控制镇定内部动态,所设计控制器能保证闭环系统的指数稳定性.仿真结果表明了所提出方法的有效性和优越性.     

线性滞后互联大系统的分散智能镇定

讨论了线性滞后互联大系统的分散镇定问题,给出了分散镇定控制器设计的思想 和方法,而后将人工神经网络技术引入该研究领域,给出了一般线性定常系统闭环极点配置 的智能方法,同时实现了线性滞后互联大系统分散镇定控制器的智能设计.最后给出了一数 值仿真例子,进而验证了该设计方法的可行性及有效性.     

基于采样控制的一类本质非线性系统的全局镇定

针对一类含不确定参数的本质非线性系统,基于非光滑控制技术,提出了 一种基于采样控制的全局非光滑镇定方案. 首先,基于加幂积分技术和递归设计方法,提出了一类采样状态反馈控制器构造性设计方法.然后,通过合理地构造Lyapunvo泛函,严格地证明了存在一个最大采样周期 可以保证闭环系统的全局渐近稳定性. 由于控制器是离散形式的,所以在实际中易于用计算机来实现. 仿真结果验证了该方法的有效 性.     

线性时变系统的一种鲁棒镇定控制器设计方法

针对一类线性时变系统提出一种状态反馈镇定控制器设计方法,该反馈控制器能将线性时变系统转化为一个稳定的定常闭环系统.借助线性系统的特征结构配置参数化方法,得到含待求参数的控制器解析形式,并给出控制器的可解性判据.在满足可解性的基础上,进一步对控制器进行了多目标优化设计,使其在保证系统稳定性的同时,具有良好的鲁棒性和干扰抑制能力.通过一个时变卫星姿态控制系统的实际设计表明了该方法的有效性.     

一类二阶非线性系统的有限时间状态反馈镇定方法

针对一类二阶非线性系统的有限时间状态反馈镇定问题进行了讨论. 给出了三种基于连续状态反馈的全局有限时间状态反馈镇定方法. 首先，利用非线性齐次系统性质，设计出一种状态反馈控制器，使得闭环系统渐近稳定并且具有负的齐次度；其次，基于有限时间Lyapunov函数的反步构造法，给出了一种有限时间控制器；最后，利用非奇异终端滑模控制技术，得到了一种使闭环系统有限时间收敛到平衡点的反馈镇定控制器. 仿真结果表明了这些方法的有效性.     

约束不确定非线性系统的鲁棒优化镇定

针对状态和输入约束不确定非线性仿射系统,提出一种鲁棒镇定的优化控制器设计方法.基于弱鲁棒控制Lyapunov函数概念,构造一个参数可调控制器.再利用LaSalle定理和逆优化理论,验证该控制器的鲁棒镇定性和逆最优性.进一步,采用滚动优化原理在线计算控制器的可调参数,实现闭环系统的鲁棒优化镇定.最后对一个开环不稳定振荡器系统进行鲁棒优化镇定,其结果验证了文中方法的有效性.     

基于干扰抑制控制的飞行器姿态跟踪

本文针对飞行器姿态跟踪控制问题, 考虑系统的内部模型不确定性和外界扰动, 设计了使跟踪误差一致最终有界的控制器. 以四元数为姿态参数, 建立系统的非线性误差模型; 将控制系统分为内环观测器和外环控制器分别设计, 其中, 线性扩张状态观测器作为系统内环将实际系统补偿为标称模型, 而外环非线性控制器则用于镇定非线性标称系统. 最后, 利用Lyapunov理论得到了一致最终有界的稳定性结论, 并基于频域理论, 分析了线性扩张状态观测器阶次对系统性能的影响. 姿态跟踪实验表明, 本文设计的控制系统能够有效实现飞行器的姿态跟踪控制.     

高阶不确定非线性系统线性状态反馈自适应控制设计

研究了一类控制系数未知的高阶不确定非线性系统的自适应镇定控制设计. 尽管该问题已经得到解决,但是所设计的控制器是非线性反馈形式,较为复杂. 与现有文献不同,本文通过综合运用增加幂积分技术和切换自适应控制方法,给出了该控制问题的更为简单且易于实现的新型线性反馈控制器,使得系统状态有界且最终趋于零. 值得指出的是,与切换自适应控制文献相比,本文所研究的非线性系统具有更严重的不确定/未知性和更强的非线性,这主要体现在未知的系统控制系数和更高的系统幂次中.     

仿射非线性奇异系统的反馈控制与稳定化

研究非线性奇异系统的反馈稳定化问题，首先给出仿射非线性奇异系统反馈稳定化的概念；然后利用零动态算法构造的局部坐标变换给出仿射非线性奇异系统的一种标准型，并将其用于研究仿射非线性奇异系统的反馈控制和系统稳定化问题；最后证明了对于正则仿射非线性奇异系统，当其零动态渐近稳定时，该系统可通过反馈控制实现系统的稳定化。     

LQ control for constrained continuous-time systems

A design method of LQ optimal control law is considered for constrained continuous-time systems. By introducing singular value decomposition for finite-time horizon linear systems, the sequence of LQ sub-optimal control laws, which converges to the exact solution, is obtained based on quadratic programming. It is also shown that the nonlinear sub-optimal feedback gain is found by the union of affine state functions.     

Anti‐windup synthesis for nonlinear dynamic inversion control schemes

A general anti‐windup (AW) compensation scheme is provided for a class of input constrained feedback‐linearizable nonlinear systems. The controller considered is an inner‐loop nonlinear dynamic inversion controller, augmented with an outer‐loop linear controller, of arbitrary structure. For open‐loop globally exponentially stable plants, it is shown that (i) there always exists a globally stabilizing AW compensator corresponding to a nonlinear generalization of the Internal‐Model‐Control (IMC) AW solution; (ii) important operator theoretic parallels exist between the AW design scheme for linear control and the suggested AW design scheme for nonlinear affine plants and (iii) a more attractive AW compensator may be obtained by using a nonlinear state‐feedback term, which plays a role similar to the linear state‐feedback term in linear coprime factor‐based AW compensation. The results are demonstrated on a dual‐tank simulation example. Copyright © 2009 John Wiley & Sons, Ltd.     

Observers for Takagi-Sugeno fuzzy systems

We focus on the analysis and design of two different sliding mode observers for dynamic Takagi-Sugeno (TS) fuzzy systems. A nonlinear system of this class is composed of multiple affine local linear models that are smoothly interpolated by weighting functions resulting from a fuzzy partitioning of the state space of a given nonlinear system subject to observation. The Takagi-Sugeno fuzzy system is then an accurate approximation of the original nonlinear system. Our approach to the analysis and design of observers for Takagi-Sugeno fuzzy systems is based on extending sliding mode observer schemes to the case of interpolated multiple local affine linear models. Thus, our main contribution is nonlinear observer analysis and design methods that can effectively deal with model/plant mismatches. Furthermore, we consider the difficult case when the weighting functions in the Takagi-Sugeno fuzzy system depend on the estimated state.     

一类不确定非线性系统的鲁棒H∞控制

讨论了在自由系统和输入通道都带有有界不确定性的仿射非线性系统的鲁棒H∞ 控制问题,给出了状态反馈控制设计,对所有允许的不确定性它既能保证关于H∞模的干扰 抑制品质,又能镇定该系统.同时指出如果一个相应的Hamilton-Jacobi不等式有非负解,则 该不确定仿射非线性系统的鲁棒H∞控制问题可解.     

不确定非仿射系统的引入动态逆的自抗扰控制器设计

针对一类不确定非仿射严反馈非线性系统, 提出一种引入动态逆的线性自抗扰控制器设计方法. 首先, 利 用微分同胚映射将严反馈非线性系统变换为积分串联型系统, 然后针对积分串联型系统设计线性自抗扰控制器. 提出的线性自抗扰控制器将闭环系统划分为3个时间尺度, 其中线性扩张状态观测器位于最快的时间尺度上, 用来 估计系统的状态和总和扰动, 动态逆位于次快的时间尺度上用以求解非仿射情况下的控制律, 系统动态位于最慢的 时间尺度上. 利用奇异摄动理论分析了闭环系统的稳定性和性能. 提出的自抗扰控制设计方法同样适用于控制增 益不确定的仿射非线性系统. 仿真和实验结果验证了提出的线性自抗扰控制器的可行性.     

Analysis and design of an affine fuzzy system via bilinear matrix inequality

A novel analysis and design method for affine fuzzy systems is proposed. Both continuous-time and discrete-time cases are considered. The quadratic stability and stabilizability conditions of the affine fuzzy systems are derived and they are represented in the formulation of bilinear matrix inequalities (BMIs). Two diffeomorphic state transformations (one is linear and the other is nonlinear) are introduced to convert the plant into more tractable affine form. The conversion makes the stability and stabilizability problems of the affine fuzzy systems convex and makes the problems solvable directly by the convex linear matrix inequality (LMI) technique. The bias terms of the fuzzy controller are solved simultaneously together with the gains. Finally, the applicability of the suggested method is demonstrated via an example and computer simulation.     

Partial‐state stabilization and optimal feedback control

In this paper, we develop a unified framework to address the problem of optimal nonlinear analysis and feedback control for partial stability and partial‐state stabilization. Partial asymptotic stability of the closed‐loop nonlinear system is guaranteed by means of a Lyapunov function that is positive definite and decrescent with respect to part of the system state, which can clearly be seen to be the solution to the steady‐state form of the Hamilton–Jacobi–Bellman equation and hence guaranteeing both partial stability and optimality. The overall framework provides the foundation for extending optimal linear‐quadratic controller synthesis to nonlinear nonquadratic optimal partial‐state stabilization. Connections to optimal linear and nonlinear regulation for linear and nonlinear time‐varying systems with quadratic and nonlinear nonquadratic cost functionals are also provided. Finally, we also develop optimal feedback controllers for affine nonlinear systems using an inverse optimality framework tailored to the partial‐state stabilization problem and use this result to address polynomial and multilinear forms in the performance criterion. Copyright © 2015 John Wiley & Sons, Ltd.     

一类仿射非线性网络控制系统的稳定性分析

利用采样数字控制系统的方法分析了一类混杂动态系统模型描述的仿射非线性网络控制系统的稳定性问题.针对一类仿射非线性对象和线性数字控制器组成的网络控制系统，考虑了网络诱导延时对系统稳定性的影响，得到了仿射非线性网络控制系统一致渐近稳定的条件．仿真实例验证了理论分析的正确性．     

Unknown input observer for state affine systems: A necessary and sufficient condition

The problem of designing an unknown input observer for linear systems and its application to fault detection is widely studied in the literature. For nonlinear systems, only subclasses of nonlinear systems and sufficient conditions have been stated. In this paper an unknown input observer design for state affine systems is considered. Based on the geometric approach, a necessary and sufficient condition is given for the existence of an unknown input observer.