参数鲁棒镇定问题的可解性必要条件

给定对象族P(s,δ)其参数是向量p范数有界的不确定参数δ的仿射函数.用根轨迹 法证明,P(s.δ)的任意两个元素的可同时镇定性等价于P(s.δ)的每个元素的可镇定性.结果表 明,P(s,δ)的可镇定性可作为一个有效的判断条件以排除那些鲁棒镇定问题肯定无解的情况, 从而更加有效的应用棱边和顶点等已知结果寻找鲁棒镇定问题的解.     

基于互质因子摄动的反馈系统的鲁棒稳定性

考虑对象和控制器同时具有互质因子摄动时闭环系统的鲁棒稳定性问题,得到了闭环 系统鲁棒稳定的充要条件并给出了鲁棒控制器的优化设计方法.     

离散系统回路成形设计与鲁棒稳定性

本文首先给出了离散系统鲁棒稳定的充要条件及规范化互质分解因子摄动的鲁棒镇定问题,在此基础上讨论了如何在回路成形设计问题中考虑鲁棒稳定性的要求.     

含参数不确定性系统的鲁棒性能设计

讨论含有参数不确定性系统的鲁棒性能设计问题。首先将该问题转化为一个多项式簇的鲁棒稳定性问题，从而得到鲁棒性能控制器应满足的频域充要条件，然后通过一个双回路控制器的设计将鲁棒镇定和鲁棒性能设计分两步进行，使设计条理化、简单化。     

具有结构不确定性的输出反馈线性系统的鲁棒稳定性分析

基于向量的幂变换方法，对具有结构不确定性的输出反馈线性系统的鲁棒稳定性问题作了分析。单参数摄动时给出了闭环系统鲁棒稳定的充要条件，多参数摄动时得到了保证系统鲁棒稳定的充分条件，导出了闭环系统鲁棒稳定区域的一种代数表达形式。最后给出了实例。     

具有结构不确定性的输出反馈性系统的鲁棒稳定性分析

基于向量的幂变换方法，对具有结构不确定性的输出反馈线性系统的鲁棒稳定性问题作了分析。单参数摄动时给出了闭环系统鲁棒稳定的充要条件，多参数摄动时得到了保证系统鲁棒稳定的充分条件，导出了闭环系统鲁棒稳定区域的一种代数表达形式。最后给出了实例。     

多项式理论在导弹稳定性能评估中的应用

针对线性参数不确定性系统的鲁棒稳定性问题,提出一种新的分析方法,并对其在导弹自动驾驶仪鲁棒稳定性评估中的可行性进行了研究。首先给出线性参数不确定性系统在其特征多项式系数不相关情况下的鲁棒稳定性的充要条件,并通过自适应网格划分算法将此条件与鲁棒D-稳定性理论结合,得到基于多项式理论的评估算法。将算法用于导弹自动驾驶仪鲁棒稳定性评估,得到了不同攻角下导弹在全包线范围内的稳定区域。和只能在离散点进行评估的传统评估方法比较,结果表明提出的算法可以在全包线范围内连续进行评估,从而发现一些隐蔽的不稳定区域。     

具有结构不确定性的线性反馈控制系统的鲁棒稳定性

本文研究了具有结构不确定性(Structured Uncertainty)因素的反馈控制系统的鲁棒稳 定性问题,对于一个普通的补偿器,给出了闭环系统鲁棒稳定的充要条件,当补偿器满足某些 假设条件时,得出了闭环系统鲁棒稳定的有限检验的充分必要条件.     

时滞不确定系统DMC约束控制的鲁棒性条件

讨论具有控制变量约束的时滞线性不确定系统DMC算法的鲁棒稳定性充要条件,共有两个部分：1）线性时滞DMC约束控制算法,通过在预测模型中引进模型误差补偿时ε1（k)和干扰修正量ε2（k)来补偿预测输出,减小预测误差;2）给出闭环系统鲁棒稳定的充要条件,得出了保证系统鲁棒性的模型误差,干扰、预测误差、跟踪误差以及期望输出各量之间的定量关系。     

等时切换下线性切换系统的稳定性及鲁棒稳定性研究-LMI方法

研究等时切换下线性切换系统的稳定性及鲁棒稳定性问题。文中首先提出等时切换的概念。然后利用LMI方法推导出等时切换下线性系统稳定及鲁棒稳定的充要条件，使用这两个充要条件可以将文中研究的复杂问题转化为相应的易处理的线性系统的问题，再利用线性系统已有的结论使问题得到解决。使用上述结果，本文为系统设计了鲁棒控制器。文中还给出实现线性切换系统等时切换的具体方法，这使等时切换方法可以真正应用于工程实践。大量仿真证实文中所提出的方法简洁、有效。     

Necessary and sufficient conditions for robust oscillatory stability

The problem of robust oscillatory stability of uncertain systems is investigated in this article. For the uncertain systems, whose characteristic polynomial sets belong to the interval polynomial family or diamond polynomial family, sufficient and necessary conditions are given based on the stability and/or oscillation properties of some special extreme point polynomials. A systematic approach exploiting Yang's complete discrmination system is proposed to check the robust oscillatory stability of such uncertain systems. The proposed method is efficient in computation and can be easily implemented.     

Frequency domain criteria for lp-robuststability of continuous linear systems

Necessary and sufficient criteria in the frequency domain for robust stability are given under the assumption that coefficients of a characteristic polynomial belong to a transformed l^p-ball. Three cases are considered in detail: p =∞ (interval uncertainty), p=2 (ellipsoidal uncertainty), and p=1 (octahedral uncertainty). It is shown that frequency-domain-stability criteria are efficient when one deals with robust stability problems. The frequency-domain approach considered can be extended to various problems of robust stability     

Real and complex polynomial stability and stability domain construction via network realizability theory

Network realzability theory provides the basis for a unified approach to the stability of a polynomial or a family of polynomials. In this paper conditions are given, in terms of certain decompositions of a given polynomial, that are necessary and sufficient for the given polynomial to be Hurwitz. These conditions facilitate the construction of stability domains for a family of polynomials through the use of linear inequalities. This approach provides a simple interpretation of recent results for polynomials with real coefficients and also leads to the formulation of corresponding results for the case of polynomials with complex coefficients.     

New results on robust stability for differential-difference systems with affine linear parametric uncertainty

This article presents sufficient conditions to verify the robust stability property of convex combinations for quasipolynomials that represent the characteristic equation of differential-difference dynamics systems. It considers affine linear parametric uncertainty structure in the coefficients of quasipolynomials and also, interval uncertainty in the time delay. First of all, a transformation of the delay's operator is performed in order to get a two variable polynomial; after this, to obtain the robust stability property, a result based on the Hurwitz matrix is applied.     

Construction of value set for robustness analysis via circular arithmetic

Circular arithmetic technique is developed for constructing value set of a characteristic polynomial. It provides necessary and sufficient conditions for robust stability of disk polynomials and their simple combinations. In more complicated cases sufficient conditions can be obtained. Various examples including multilinear (real or complex) parameter perturbations are considered.     

Robust stability of state-space models with structureduncertainties

A method for robust eigenvalue location analysis of linear state-space models affected by structured real parametric perturbations is proposed. The approach, based on algebraic matrix properties, deals with state-space models in which system matrix entries are perturbed by polynomial functions of a set of uncertain physical parameters. A method converting the robust stability problem into nonsingularity analysis of a suitable matrix is proposed. The method requires a check of the positivity of a multinomial form over a hyperrectangular domain in parameter space. This problem, which can be reduced to finding the real solutions of a system of polynomial equations, simplifies considerably when cases with one or two uncertain parameters are considered. For these cases, necessary and sufficient conditions for stability are given in terms of the solution of suitable real eigenvalue problems     

Schur stability and stability domain construction

A discrete version of Foster's reactance theorem is developed and, subsequently, used to delineate necessary and sufficient conditions for a given polynomial with complex or real coefficients to be of the Schur type. These conditions, obtained from the decomposition of a polynomial into its circularly symmetric and anti-circularly symmetric components, facilitate the construction of stability domains for a family of polynomials through the use of linear inequalities. These results provide the complete discrete counterpart of recent results for a family of polynomials which are required to be tested for the Hurwitz property.     

Stability analysis and guaranteed domain of attraction for a class of hybrid systems: an LMI approach

This paper presents sufficient conditions for the regional stability problem for switched piecewise affine systems, a special class of Hybrid Systems. This class of systems are described by an affine differential equation of the type x˙=A(δ)x+b(δ), where x denotes the continuous state vector and δ is a vector of logical variables that modifies the local model of the system in accordance with the continuous dynamics. Using a Lyapunov function of the type v(x)=x′P(x)x, we present LMI conditions that, when feasible, guarantee local stability of the origin of the switched system. Examples of switched affine systems are used to illustrate the results. Copyright © 2003 John Wiley & Sons, Ltd.