鲁棒严格正实控制器设计

基于强严格正实引理使用线性矩阵不等式方法讨论了参数不确定线性系统鲁棒严格正实控制器的综合问题,提出了二次严格正实的新概念,证明了静态状态反馈解的存在性,并给出了状态反馈壮次严格正实控制器的存在条件和综合方法。     

广义系统输出反馈严格正实控制器设计

研究连续广义系统的正实控制问题。目的是设计静态输出反馈和动态输出反馈严格正实控制器使得闭环系统容许且扩展严格正实。基于广义系统严格正实引理，利用线性矩阵不等式和广义代数Riccati不等式，给出了广义系统静态输出反馈和动态输出反馈严格正实控制器存在的充要条件及设计方法。对动态输出反馈情形，给出了一个数值算例说明控制器设计方法的有效性及可行性。     

独立摄动参数不确定线性系统的正实控制

考虑了一类范数有界参数不确定线性系统的鲁棒正实性分析和设计问题,其中参数不确定性是独立摄动的．通过构造增广系统将不确定系统的鲁棒正实分析和控制问题转化为确定系统的情形,给出了鲁棒正实分析问题的线性矩阵不等式解法,导出了输出反馈控制器的存在条件．所得结论将范数有界参数不确定系统的鲁棒正实分析和控制的现有结果推进了一步．     

输出反馈严格正实控制器设计

基于强严格正实引理，采用线性矩阵不等式方法讨论一般严格正实控制问题的解，给出了任意阶输出反馈严格正实控制器的存在条件和所有控制器的参数化形式。     

线性广义系统基于观测器的严格耗散控制

研究线性广义系统基于观测器的严格耗散控制器的设计问题。首先利用Lyapunov函数的方法,由矩阵不等式的形式给出满足要求的基于观测器的控制器存在的一个充分条件,保证闭环广义系统容许（即正则、稳定、无脉冲）且严格耗散。进而在上述条件的基础上,通过矩阵缩放技术和矩阵等价变换得到由线性矩阵不等式（LMI）形式给出的满足要求的控制器的存在条件和设计方法。最后给出一个数值算例说明设计方法的有效性及可行性。     

一种不需要严正实条件的模型参考自适应控制

对于具有未建模动态ηn的系统（1）和（2）,考察了模型参考自适应控制问题。利用有界的外部激励和随机变向截尾技术,我们给出了一种类似于（1）的模糊参考自适应控制器的设计。对于这种控制器,我们证明了闭环系统是全局稳定的,建模部分的参数估计是0（ε）,且这种模型参考自适应控制器在lim supn→∞1/n∑^n i=0(Am(z)yi 1-Bm(z)zi^*-Cm(z)wi 1)^2≤0(ε^2) γ^2b1^2意义下是次优的,而其他文献中利用的严正实条件减弱为稳定性条件。     

线性奇异时滞系统的观测器设计

Two kinds of observers for linear singular time-delay systems, namely functional observers and full-order observers, are considered in this paper. For the former, observers with and without internal delay are considered. For the latter, observers without internal delay is given. The corresponding design steps for various observers, which are all normal linear time-delay systems, are presented. Numerical examples are given to illustrate the methods.     

Observer Design for Linear Singular Time-delay Systems

Two kinds of observers for linear singular time-delay systems,namely functional ob- servers and full-order observers,are considered in this paper.For the former,observers with and without internal delay are considered.For the latter,observers without internal delay is given.The corresponding design steps for various observers,which are all normal linear time-delay systems,are presented.Numerical examples are given to illustrate the methods.     

线性时变离散系统的状态观测器

本文放弃了Ｌｕｅｎｂｅｒｇｅｒ状态观测器理论对系统完全可观测性的要求，提出了一般线性时变离散系统的状态观测器设计方法，并对ｊ＝ｉ，ｉ－１给出了系统完全（ｉ，ｊ，Ｔｉ）－可重构这一新概念的充要条件。     

Event-triggered Control of Positive Systems With State Saturation Using Linear Programming

This paper proposes the event-triggered control of positive systems with state saturation both in discrete-time and continuous-time cases. A 1-norm based event-triggered mechanism is established for positive systems. Under the event-triggered mechanism, the error term between actual and sample states is transformed into interval uncertain form. Together with the properties of saturation, the systems with state saturation are transformed into interval uncertain systems and the corresponding lower and upper bounds of the system matrices are obtained, respectively. Using a linear co-positive Lyapunov function, the event-triggered controller and the auxiliary gain matrix of the domain of attraction are designed in terms of linear programming, respectively. Then, the systems with state and input saturation are also described via interval uncertain systems. An event-triggered controller is designed and thus the closed-loop systems are positive and stable under the designed controller. Furthermore, the presented event-triggered control approach is extended to the continuous-time case. Compared to existing control approaches, the event-triggered control can reduce energy consumption and increase the practicability. Finally, several numerical examples are given to illustrate the effectiveness of the proposed design.

     

反馈严格正实输出的必要与充分条件

本文研究线性多输入多输出系统反馈成为严格正实系统问题，得到了反馈严格正实系统的必要和充分条件，这个条件在表达上十分简洁。由于这个条件的检验仅需考虑系统矩阵，控制矩阵及输出矩阵间的某种确定系统，从而便于实际使用。     

Real Solving for Positive Dimensional Systems

Finding one point on each semi-algebraically connected component of a real algebraic variety, or at least deciding if such a variety is empty or not, is a fundamental problem of computational real algebraic geometry. Although numerous studies have been done on the subject, only a small number of efficient implementations exist.In this paper, we propose a new efficient and practical algorithm for computing such points. By studying the critical points of the restriction to the variety of the distance function to one well chosen point, we show how to provide a set of zero-dimensional systems whose zeros contain at least one point on each semi-algebraically connected component of the studied variety, without any assumption either on the variety (smoothness or compactness for example) or on the system of equations which define it.From the output of our algorithm, one can then apply, for each computed zero-dimensional system, any symbolic or numerical algorithm for counting or approximating the real solutions. We report some experiments using a set of pure exact methods. The practical efficiency of our method is due to the fact that we do not apply any infinitesimal deformations, unlike the existing methods based on a similar strategy.     

L∞ Observer for Uncertain Linear Systems

In this paper, an L_∞ observer design method is proposed for linear system subject to parameter uncertainty and bounded disturbance. The proposed L_∞ observer, which satisfies a peak‐to‐peak disturbances attenuation performance, is designed to overbound the estimation error. Moreover, sufficient conditions for the design of L_∞ observer are derived and expressed in terms of linear matrix inequalities (LMIs). The novelty of the proposed method is that we develop an L_∞ observer that not only can attenuate bounded disturbance but also provides an upper bound of estimation error norm. Simulation results are presented to illustrate the effectiveness of the proposed method.     

反馈正实系统和Stalford问题

本文讨论系统的反馈正实性和Stalford问题:1)给出了系统Σ(C,A,B)为反馈正实的新的充分必要条件;2)对Stalford问题,证明了由Chao和Stalford给出的必要条件也是充分条件.此外还将Stalford问题推广到系统不可控的情况,并给出了易于检验的充分必要条件.     

Comments On "an Asymptotic Modal Observer For Linear Autonomous Time Lag Systems"

It is show that the proof of theorem 1 in the original paper of J. Leyva-Ramos and A.E. Pearson (ibid., vol. 40, p. 1291-4, 1995) is incomplete and that the state observer scheme results in steady-state error. Alternatively, a memoryless state observer for linear time-delay systems is provided. The original authors acknowledge that the criticism is correct, and suggest an alternative way of overcoming the problem     

Open‐Loop Functional Observer and State Feedback for Linear Systems Using Multirate Output Sampling

In this paper, the problem of estimating a linear functional of the state vector is considered in order to implement a feedback control law for discrete‐time linear multivariable systems. The proposed method is based on multirate sampling of the plant output. We give necessary and sufficient conditions for the existence of the functional observer, and propose a functional observer with the minimal number of output samples. In this work, the control law is implemented using the output samples, thus this methodology is more practical than state based techniques. A numerical example is considered to illustrate the procedure and highlight the advantages of the proposed method.     

Positive Controllability Test for Continuous-Time Linear Systems

This note presents a method to test the positive controllability of a continuous-time linear system. Based on the Jordan canonical form, the controllability of a given system can be reduced to those of its subsystems with real eigenvalues. Because the dimension of the subsystem is smaller than that of the given system, the controllability test can be simplified. It is pointed out that the conditions for a continuous-time system to be positive controllable have almost the same expressions as those for a discrete-time system.     

广义系统正实反馈控制的一种新方法

研究了广义连续系统的扩展严格正实的控制问题.首先,利用与原系统等价的增广系统和矩阵分解,给出了广义系统正则,无脉冲,稳定且扩展严格正实的一个新的充分必要条件.并且此条件是便于Matlab求解的严格线性矩阵不等式形式.其次,基于此定理和线性矩阵不等式的性质,给出了保证闭环系统是正则,无脉冲,稳定且ESPR的控制器设计方法.最后通过2个数值算例说明了所提出方法的有效性和可行性.     

基于干扰观测器的不确定线性多变量系统控制

针对不确定线性多变量系统,提出一种基于干扰观测器(Disturbance observer,DOB)的保证系统内部稳定性的控制策略.以简单的结构和少量的计算代价实现鲁棒的控制效果,补偿外界干扰以及内部模型误差.通过引入一个闭环稳定性等价系统,辅助分析基于干扰观测器的多变量控制系统的内部稳定性,探讨在存在外部扰动及内部模型不确定性的情况下系统保证内部稳定的充分条件,指导外环控制器及内环干扰观测器中Q滤波器的设计.通过数值模型上的仿真验证了提出的控制方法的有效性.     

广义时滞系统的降维观测器设计

讨论广义时滞系统的降维观测器的设计方法．通过引入矩阵的广义逆矩阵,给出在一定条件下降维观测器的具体形式,然后分别利用广义逆矩阵及Lyapunov函数方法给出这些条件成立的具体条件及验证方法。最后给出一个例子来说明方法的有效性。