摘要:

A polynomial-based ARMA model, when posed in a state-space framework can be regarded in many different ways. In this paper two particular state-space forms of the ARMA model are considered, and although both are canonical in structure they differ in respect of the mode in which disturbances are fed into the state and output equations. For both forms a solution is found to the optimal discrete-time observer problem and algebraic connections between the two optimal observers are shown. The purpose of the paper is to highlight the fact that the optimal observer obtained from the first state-space form, commonly known as the innovations form, is not that employed in an optimal controller, in the minimum-output variance sense, whereas the optimal observer obtained from the second form is. Hence the second form is a much more appropriate state-space description to use for controller design, particularly when employed in self-tuning control schemes.

ISSN:0020-7179    

DOI:10.1080/00207178708933989

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Relationships between asymptotic stability and exponential stability are investigated. It is shown that asymptotically stable but not exponentially stable non-linear systems are structurally unstable and hence of little practical interest.

ISSN:0020-7179    

DOI:10.1080/00207178708933990

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

In this paper, we investigate a model reference adaptive control problem for the class of distributed parameter systems generated by spectral operators. First we present an equivalent static input-output representation for the spectral system using filtered values generated from the inputs and the outputs. Next, we design and analyse a model reference adaptive control system for systems with unknown input and output distribution functions.

ISSN:0020-7179    

DOI:10.1080/00207178708933991

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A design method for type-1 servo systems having prescribed stability margins at the control input and error channels is presented. The former and latter stability margins affect the properties of sensitivity and robustness and the transient response characteristics, respectively. As a preliminary, a class of state feedback laws for regulators that possess a prescribed stability margin is parametrized by means of a generalized Riccati-type equation. This is applied to designing servo systems, which enables us to specify the stability margins at the above two portions. We can improve the output response of the system by the proposed design procedure and the effect is ascertained by an example. The integrity at the error channel is also investigated.

ISSN:0020-7179    

DOI:10.1080/00207178708933992

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The stability robustness of discrete linear time-invariant systems in state-space models is analysed. Based on a root-locus approach and from the stable-eigenvalue viewpoint, fundamental criteria for testing the stability robustness of autonomous systems are derived and applied to the robustness analysis of multivariable feedback systems. Both the norm bound and the element bounds for the allowed perturbations are obtained. A stability robustness index is denned which is useful both for the analysis and synthesis of control systems.

ISSN:0020-7179    

DOI:10.1080/00207178708933993

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This paper presents an approach for the control of linear systems with parameter uncertainty. The parameter uncertainty under consideration is assumed to be unknown but bounded and can exist in both state and input matrices. Using the linear quadratic optimal control formulation, we consider a cost functional which is parameterized by uncertainties. An upper bound on the cost which is incurred by state feedback control and system uncertainties is obtained, and a linear state feedback law is found to minimize the upper bound. Furthermore, under the conditions presented in this paper the steady-state bound-minimizing control gain is shown to exist and the stability of the resultant closed-loop systems is guaranteed for all admissible uncertainties. Finally, a gradient search algorithm is proposed to find the optimal values of the free parameters which affect the cost upper bound. A numerical example is included to demonstrate the effectiveness of the proposed method.

ISSN:0020-7179    

DOI:10.1080/00207178708933994

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The optimal projection equations for quadratically optimal centralized fixed-order dynamic compensation are generalized to the case in which the dynamic compensator has, in addition, a fixed decentralized structure. Under a stabilizability assumption for the particular feedback configuration, the resulting optimality conditions explicitly characterize each subcontroller in terms of the plant and remaining subcontrollers. This characterization associates an oblique projection with each subcontroller and suggests an iterative sequential design algorithm. The results are applied to an interconnected flexible beam example.

ISSN:0020-7179    

DOI:10.1080/00207178708933995

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A newly developed frequency-domain optimization approach for solving the model matching problem, perfect or imperfect, is presented. A new necessary and sufficient condition for perfect model matching in linear multivariable systems is derived, which, if satisfied, results in an exact model matching control system. If the perfect matching condition fails, an optimal approximation design can be used so that the controlled system responds in a manner approximating to the chosen model. Compared with existing methods, the proposed optimization method is conceptually simpler.

ISSN:0020-7179    

DOI:10.1080/00207178708933996

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The Lyapunoy stability of a form of singularly perturbed bilinear system is investigated. A theorem is proposed to show how to calculate the stabilizing controller for the whole system from a knowledge of the stability of the reduced-order model. A numerical example is given.

ISSN:0020-7179    

DOI:10.1080/00207178708933997

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The piecewise linear polynomial function approach to the minimum energy control of linear systems with time delay, is presented in this paper. The concepts of a delay shift matrix and an operational matrix for integration are employed in solving the related state and costate equations containing terms with advanced and delayed arguments. An attractive feature of the present method is its ultimate simplicity and convenience. The differential equations with delay and advance terms are converted into a set of linear algebraic equations using a recurrence algorithm. An example demonstrates the accuracy of the method.

ISSN:0020-7179    

DOI:10.1080/00207178708933998

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor