具有时变状态滞后2-D离散系统的稳定与镇定(英文)

针对一类由局部状态空间(LSS)Fornasini-Marchesini(FM)第二模型描述的,具有时变状态滞后的2-D离散系统,其中时变滞后项的上、下界均为正实数,研究了其稳定性和控制综合问题。首先,利用Lyapunov-Krasovski泛函方法,提出了系统的稳定性准则。再根据这一准则,分别设计状态反馈和动态输出反馈控制器保证系统的稳定性。状态反馈控制律和输出反馈矩阵可由线性矩阵不等式(LMI)求得。最后,通过数值算例说明所得结果的有效性。     

具有区间时变时滞2-D 离散系统的时滞相关稳定与控制

针对具有区间时变时滞2-D离散系统,利用时滞相关方法,研究其稳定性与控制问题.首先选取含有时滞项上、下界的一个新的Lyapunov函数,对其差分时考虑所有项,得到了基于线性矩阵不等式(LMI)的时滞相关稳定性准则;然后给定时变时滞项的下界,再由一个凸优化问题最大化其上界,进而通过状态反馈实现系统的时滞相关控制,且求解LMI可得到增益矩阵;最后,利用数值算例说明了所得结果有效且优于已有成果.     

一类线性时变系统的输出反馈控制

基于线性时不变系统能控能观标准型变换及非线性系统高增益观测器方法,本文研究了一类线性时变系统 的输出反馈控制问题. 通过引入时变的状态变量坐标变换,分别设计了线性时变系统的状态反馈控制器、状态观测器以及基于 状态观测器的输出反馈控制器. 进一步地,本文分别证明了观测器动态误差是渐近收敛于零的,而状态反馈控制器以及输出反馈控制器可以 保证闭环系统的渐近稳定性.     

一类非线性时变系统基于观测器的反馈稳定化

1　引言目前,有关非线性系统的状态反馈控制已取得了许多引人注目的研究结果,其中状态可测是此控制方法中的一个必不可少的假设.在实际中,许多系统的状态是部分可测或不完全可测,故构造观测器,并用估计状态实现反馈控制是一个非常有意义的研究工作.本文研究了一类仿射非线性时变系统基于状态观测器的输出反馈稳定控制问题.首先设计了系统的状态观测器,然后综合控制器和观测器得到了非线性输出反馈控制器,并证明了反馈后闭环系统的指数稳定性.研究结果表明,系统的控制器与观测器可以分离独立进行设计.2　系统的描述及预备知识考虑下列非线性…     

广义不确定周期时变系统的鲁棒稳定性分析

研究广义不确定周期时变系统的鲁棒稳定性问题.基于广义周期时变系统Lyapunov不等式,提出了广义不确定周期时变系统鲁棒稳定的概念,采用矩阵不等式(LMI)方法,得到了该类系统鲁棒稳定的充分必要条件;然后,进一步研究了在状态反馈控制下保证闭环系统鲁棒稳定的条件,给出了一族状态反馈鲁棒稳定器的设计方法;最后,引入了广义周期时变系统二次稳定的概念,并讨论了二次稳定性与鲁棒稳定性之间的关系.     

基于神经网络的高阶随机非线性系统的状态反馈控制

基于神经网络(NN)研究了一类含有未知非线性项的高阶随机不确定系统的自适应状态反馈控制问题. 通过引入径向基函数神经网络(RBF NN) 逼近方法, 运用 backstepping 技术以及选择合适的 Lyapunov 函数, 我们构造了一个自适应状态反馈控制器使得闭环系统是半全局一致最终有界的. 仿真例子验证了设计方法的有效性.     

一类非齐次高阶非线性系统的连续反馈控制设计

研究了一类非齐次的高阶非线性系统的连续状态反馈控制设计问题. 通过定义一列适当的辅助函数,放宽了对非线性项的约束条件. 利用传统的积分反推技术,并增加一个积分项的方法,得到了这类系统的稳定性,给出了控制器的设计方法,并通过一个例子验证了本文的理论结果.     

基于观测器的输出反馈电子节气门控制器设计

针对电子节气门系统的状态变量不完全可测量, 设计了一个基于观测器的输出反馈电子节气门控制系统. 该系统由一个估计不可测量状态的降阶观测器和一个非线性状态反馈控制器组成. 同时在控制器中引入了跟踪误差的积分项以抑制跟踪静差. 将建模误差和观测器误差等不确定性看作外部扰动, 在输入到状态稳定性(Input to state stability, ISS)理论框架下分析了跟踪误差系统的鲁棒性, 并据此给出了选择控制器参数的指导性原则.仿真及实验结果表明, 基于观测器的输出反馈控制器能够很好地实现电子节气门的跟踪控制.     

基于Razumikhin 方法的随机时变时滞非线性系统的状态反馈

采用Razumikhin 方法研究一类随机时变时滞非线性系统的状态反馈镇定问题. 利用随机系统的Razumikhin-Mao 理论和反推设计方法, 设计系统的状态反馈控制器, 所设计的控制器能保证闭环系统的平衡点为依概率全局渐近稳定的. 所提出的方法能够彻底地去掉关于随机时变时滞非线性系统传统结果中所要求的时滞导数的限制. 仿真示例验证了所提出状态反馈控制器的有效性.

     

基于状态反馈控制器的多无人水面船集群控制

研究在时变环境干扰和输入饱和约束条件下,基于状态反馈控制器的多无人水面船集群控制.首先,为了准确地估计时变的海洋环境干扰,提出一种有限时间干扰观测器;然后,为了处理执行机构的物理约束,采用一种辅助动态系统;最后,为了实现多无人水面船集群控制,设计一种状态反馈控制器.采用李雅普诺夫方法证明了系统的稳定性,仿真结果验证了所设计的状态反馈控制器的有效性.     

基于Jensen 不等式的2-D 区间时变时滞系统的稳定与控制

考虑具有区间时变时滞二维(2-D) 离散系统的时滞相关稳定性和控制问题. 选取含有时滞上下界的Lyapunov 函数, 对其差分时考虑到所有项, 结合2-DJensen 不等式, 由线性矩阵不等式给出系统新的时滞相关稳定性准则. 准则中含有更少的待定变量, 降低了数值计算负担, 并且比一些已有结果具有更小的保守性. 基于稳定性准则, 由状态反馈实现了系统的稳定控制. 最后, 通过数值算例表明了所得结果的有效性和优越性.

     

基于广义扩张状态观测器的遥操作系统同步控制

针对机械臂遥操作系统中存在的时变时延问题,提出了基于广义扩张状态观测器的控制方法,实现了遥操作系统稳定并且主从机械臂关节角位置同步的控制目标。首先通过反馈线性化,将遥操作系统的主从机械臂动力学模型转化为一个关于位置跟踪误差和时延的状态空间模型。针对该多输入多输出的干扰不匹配模型,设计了广义扩张状态观测器和相应的控制律,从而消除了时变时延以及其它扰动引起的不确定性对系统的影响,并对系统进行稳定性和抗扰性分析。最后,通过仿真验证了所设计的控制方法的有效性。     

Robust MPC for polytopic uncertain systems with time-varying delays

This paper addresses robust model predictive control (MPC) for time-delay systems with polytopic uncertainty. Uncertain time-varying input delay and state delays are considered, and the infinite horizon control moves are parametrised into an augmented state feedback law at each time instant. A receding horizon implementation of this state feedback law renders satisfaction of input/state constraints and closed-loop stability. For time-invariant delays and known delays, simplified results are obtained. A numerical example and a benchmark problem on continuous stirred tank reactor (CSTR) are given to illustrate the effectiveness of the proposed techniques.     

Adaptive robust stabilisation for a class of uncertain nonlinear time-delay dynamical systems

The problem of adaptive robust stabilisation is considered for a class of uncertain nonlinear dynamical systems with multiple time-varying delays. It is assumed that the upper bounds of the nonlinear delayed state perturbations are unknown and that the time-varying delays are any non-negative continuous and bounded functions which do not require that their derivatives have to be less than one. In particular, it is only required that the nonlinear uncertainties, which can also include time-varying delays, are bounded in any non-negative nonlinear functions which are not required to be known for the system designer. For such a class of uncertain nonlinear time-delay systems, a new method is presented whereby a class of continuous memoryless adaptive robust state feedback controllers with a rather simpler structure is proposed. It is also shown that the solutions of uncertain nonlinear time-delay systems can be guaranteed to be uniformly exponentially convergent towards a ball which can be as small as desired. Finally, as an application, an uncertain nonlinear time-delay ecosystem with two competing species is given to demonstrate the validity of the results.     

On designing memory state feedback controller for linear systems with interval time-varying delay

This paper is concerned with the design of a memory state feedback controller for linear systems with interval time-varying delays. The time delay is assumed to be a time-varying continuous function belonging to a given interval, which means that the lower and upper bounds of time-varying delay are available. First, a less conservative delayrange-dependent stability criteria is proposed by using a new interval fraction method. In the process of controller synthesis, the history information of system is considered in the controller design by introducing the lower delay state. Moreover, the usual memoryless state feedback controller for the underlying systems could be considered as a special case of the memory case. Finally, two numerical examples are given to show the effectiveness of the proposed method.     

Design of Adaptive Block Backstepping Controllers with Perturbations Estimation for Nonlinear State‐Delayed Systems in Semi‐Strict Feedback Form

This paper is an extended study of an existing block backstepping control scheme designed for a class of perturbed multi‐input systems with multiple time‐varying delays to solve regulation problems, where the time‐varying delays must be linear with state variables. A new control scheme is proposed in this research where all the unknown multiple time‐varying delay terms in the dynamic equations can be nonlinear state functions in non‐strict feedback form, and the upper bounds of the time‐delays as well as their derivatives need not to be known in advance. Another improvement is to further alleviate the problem of “explosion of complexity,” i.e., to reduce the number of time derivatives of virtual inputs that the designers have to compute in the design of controllers. This is done by utilizing an existent derivative estimation algorithm to estimate the perturbations in the designing of proposed controllers. Adaptive mechanisms are also embedded in the controllers so that the upper bounds of perturbations and perturbation estimation errors are not required to be known beforehand. The resultant controlled systems guarantee asymptotic stability in accordance with the Lyapunov stability theorem. Finally, a numerical example and a practical application are demonstrated to verify the merits and feasibility of the proposed control scheme.     

改进的时延丢包网络控制系统的分析和控制

将网络控制系统建模为时变时滞系统模型,考虑有界、时变时延和丢包的网络控制系统的稳定性分析和控制器设计问题。首先构造一个新的分段Lyapunov-Krasovskii泛函,充分利用时延上下界信息,然后结合更紧的有限和不等式处理时滞区间,得到具有较小保守性的稳定性准则,基于一种改进的锥补线性化迭代算法给出状态反馈器设计方法,证明中没有引进模型变换和自由矩阵,减少了计算上的复杂性。通过实例表明上述方法的有效性。     

Observer based output feedback regulation of a class of feedforward nonlinear systems with uncertain input and state delays using adaptive gain

We consider a global regulation problem of a class of feedforward nonlinear systems with uncertain delays by output feedback. The considered system is a generalized feedforward time-delay nonlinear system in the sense that an additional uncertain constant delay exists in the main control input to the system and feedforward nonlinearity includes states and input which have uncertain time-varying delays. Moreover, when feedforward nonlinearity satisfies some restrictive condition, we extend our control problem to the case such that the delay in the main control input is also a time-varying delay. To globally regulate the considered system, we develop an output feedback controller whose gain-scaling factor involves an adaptive dynamic. Two examples are given for illustration.