摘要:

The influence of state feedback on the transfer matrix in singular systems is considered. We first discuss the problem for SISO systems, then by utilizing the time-scale transformation the same problem is solved for MIMO systems. We also consider realizations of the feedback control strategies given here. It is pointed out that the singular system is distinguished from the normal one by an important feature: we can design a pure input prediction system for it. Finally, the results are applied to the model matching problem.

ISSN:0020-7179    

DOI:10.1080/00207178908559674

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The robust pole assignment of systems with linear time-invariant perturbations is considered. Based upon the Lyapunov approach, new techniques for calculating the robustness bounds for pole assignment in any chosen region are presented. These take account not only of stability robustness but also of certain types of performance robustness. Examples are presented to illustrate the merit of the proposed analysis methods.

ISSN:0020-7179    

DOI:10.1080/00207178908559675

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The order of the stabilizing controller and the closed-loop eigenvalues in LTI control systems designed using the fractional approach are studied. New insight is provided and guidelines are given to attain tighter control over the number of the closed-loop eigenvalues and the compensator order, thus avoiding unnecessarily high order controllers and computationally expensive calculations. The study is carried out using the results of Antsaklis (1986) to derive the closed-loop internal descriptions directly in terms of the proper, stable factorizations of the plant and the controller transfer matrices.

ISSN:0020-7179    

DOI:10.1080/00207178908559676

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The design of a robust observer-based compensator for imprecisely known linear multivariable systems is considered. Necessary and sufficient conditions for robust stability are derived with respect to additive plant perturbation, multiplicative plant perturbation and fractional plant perturbation. Necessary and sufficient conditions are also given for the existence of such a robust observer-based compensator.

ISSN:0020-7179    

DOI:10.1080/00207178908559677

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The problem of the stabilization of an uncertain time-delay system with a saturating actuator is discussed. These uncertainties may be linear, non-linear, and/or time-varying, but only the upper bounds are known. A linear dynamical feedback compensator is used to stabilize this uncertain saturating and time-delay system. The concept of matrix measure and the comparison theory are employed to investigate the robust stability condition which assures asymptotic stability. One example is given to illustrate the application of the proposed design method.

ISSN:0020-7179    

DOI:10.1080/00207178908559678

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The disturbance attenuation problem is studied for linear (distributed) plants described by partial differential operators and by using one lumped- (i.e. acting at a single point) feedback loop. A result emphasizing the trade-off between stability and disturbance attenuation is proven. Also, the effect of the feedback loop location on disturbance attenuation is pointed out. Finally, a synthesis procedure is derived, valid also for plants having bounded uncertainty in the gain. The procedure is illustrated by two significant examples in a one-dimensional, bounded domain.

ISSN:0020-7179    

DOI:10.1080/00207178908559679

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Systems like unstable aircraft or large space structures are inherently vulnerable to failure of components and their reliability has to be improved through fault-tolerant control: given a set of redundant components, the failed element is diagnosed by a failure detection and isolation (FDI) device and its influence is removed through a reconfiguration of the control algorithms. Performance requirements are then usually expressed in terms of a short detection delay and a low false alarm rate for the FDI function and, for example, stability of the reconfigured system. Linear systems subject to random jumps in parameter values are used to analyse the dynamic behaviour of a fault-tolerant control system and it is found that even a short detection delay and/or a low false alarm rate, when fedback in a reconfigurable control loop, significantly affect stability.

ISSN:0020-7179    

DOI:10.1080/00207178908559680

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Stability is a central issue for polynomials with variable coefficients. The stability of a class of polynomials whose coefficients are characterized by a polytope is studied. We show that the stability of this whole family of polynomials is assured if the zeros of the even and odd parts of the vertex polynomials have interlacing properties.

ISSN:0020-7179    

DOI:10.1080/00207178908559681

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Linear time-invariant systems of the formare considered. The problem is to find a control vectoru(t)that will drive the state of this system from a givenz(0) to some (not necessarily fixed) final statez(tf) in some (not necessarily fixed) timetfwhile minimizing a cost functional of the formThe original system is re-written in the form of a descriptor-variable system consisting of the equations diagIt is shown that there is a matrixsuch thatthus the original optimal control problem is equivalent to the following problem. Find a control vectoru(t)that drives the descriptor vectorx(t)from a given x(0) to somex(tf)while minimizingUsing the results of an earlier paper on optimal control of descriptor systems (Ibrahimet al.1988), necessary conditions are derived for the existence of minima of; the problem of finding sufficient conditions for the existence of minima ofis not considered. Various formulae are obtained for designing open-loop controls corresponding to three different terminal boundary conditions (tffixed,z(tf)=0;tffixed,z(tf) free;tffree,z(tf)=0). The problem of choosing the matrixQof the original cost functionalJis investigated in some detail.

ISSN:0020-7179    

DOI:10.1080/00207178908559682

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Input-output representations of non-linear discrete-time systems are discussed. It is shown that the NARMAX (Non-linear AutoRegressive Moving Average with eXogenous inputs) model is a general and natural representation of non-linear systems and contains, as special cases, several existing non-linear models. The problem of approximating non-linear input-output systems is also addressed and several properties of non-linear models are highlighted using simple examples.

ISSN:0020-7179    

DOI:10.1080/00207178908559683

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor