摘要:

In this paper some aspects of the partial realization problem for multivariable formal power series are considered. The dynamic structure of the systems underlying such series is analysed on the basis of the results of Kalman, and a canonical realization algorithm is described based on this concept of structure. Special attention is paid to the aspect of uniqueness of the realization; necessary and sufficient conditions are given for the uniqueness of the extension sequence. A specific class of power series is defined for which a very simple uniqueness criterion is derived. Generally, noise-disturbed data sequences belong to this specific class; it is shown that the unique partial realization for such a noise-disturbed power series may serve as an intermediate step to arrive at an approximate realization of limited order.

ISSN:0020-7179    

DOI:10.1080/0020718508961152

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The method of projective controls is applied to the design of static and low order dynamic output regulators for discrete-time systems. Basic properties of the projective controls approach are obtained and the relation of the associated regulator to the state regulator as well as to the standard output regulator is determined. An explicit relationship of dynamic regulators design by projective controls approach with observers is also developed and fundamental differences are highlighted.

ISSN:0020-7179    

DOI:10.1080/0020718508961153

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The time-optimal output regulator is considered for a special class of linear time-invariant discrete-time systems. It is shown that a simple state feedback law achieves time-optimal output regulator response in one sampling period. For a square system, the state feedback law always assigns the invariant zeros as closed-loop poles. For a non-square system, time-optimal regulator response is achieved even if the set of invariant zeros is empty. If the set of invariant zeros is not empty, the control law always assigns these zeros as closed-loop poles. The method of this paper, for the discrete system described by the state and output equationsx(k + 1) =Ax(k) +Bu(k) and z(k) =Cx(k), does not require thatAbe invertible and that the open-loop system S(A, B, C) be state controllable. Furthermore, the only requirement is the existence of a right inverse for the matrixCBwhich is sufficient for output controllability.

ISSN:0020-7179    

DOI:10.1080/0020718508961154

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

This paper proposes a computer-aided design methodology for linear multivariable feedback systems. This methodology utilizes a two-input controller to give two degrees of freedom in the design, and is applicable to distributed systems with unstable plants. Unlike others, this methodology obtains designs directly from plant measurements, bypassing the intermediate step of constructing a plant model. Thus the numerical problems inherent in the manipulation of polynomial and rational matrices are avoided. By formulating and solving the appropriate non-linear programming problems, this methodology can select the best design, relative to designer-specified inequality constraints and cost functions, from a globally parametrized family of designs. Such families are obtained from known results in algebraic control theory. Since the plant is specified only by isolated measurements, the compensator will only be specified by the same. Hence, the methodology suggests a procedure for realizing a lumped compensator satisfying the known measurements. Possible variations by which distributed compensators may be obtained are also suggested.

ISSN:0020-7179    

DOI:10.1080/0020718508961155

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

This paper is concerned with a method of designing a type one servomechanism for a discrete-time system subject to a time-varying demand and an unmeasurable constant disturbance. It is assumed that the time-varying demand is previewable in the sense that some finite future as well as present and past values of the demands are available at each time. A controller with state feedback plus integral and preview actions is derived by applying a linear quadratic integral (LQI) technique due to Tomizuka and Rosenthal (1979). It is shown under the stabilizability and detectability conditions that the closed-loop system achieves a complete regulation in the presence of small perturbations in system parameters, eliminating the effect of disturbance. An example of power plant control is presented to show the flexibility of the design method and the effectiveness of the preview action for improving the transient responses of the closed-loop system.

ISSN:0020-7179    

DOI:10.1080/0020718508961156

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

A method for shifting the real parts of the open-loop poles to any desired positions while preserving the imaginary parts is presented. The method is based on the mirror-image property which has been reported by Molinari. In other words, Molinari's results are extended and then a recursive approach is developed. In each step of this approach, it is required to solve a first-order or a second-order linear matrix Lyapunov equation for shifting one real pole or two complex conjugate poles respectively. The presented method yields a solution which is optimal with respect to a quadratic performance index. The attractive feature of this method is that it enables solutions to complex problems to be easily found without solving any non-linear algebraic Riccati equation.

ISSN:0020-7179    

DOI:10.1080/0020718508961157

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

In this paper necessary and sufficient conditions for target path controllability (TPC) of continuous-time dynamical systems that depend on the choice of the admissible target and control space are derived. It is shown that the well-known rank criterion of Brockett and Mesarović (1965) has to be replaced by stronger conditions for TPC by means of Lp-controls, if the target space contains not only sufficiently smooth output functions, but also functions that are not so ‘well behaved’.

ISSN:0020-7179    

DOI:10.1080/0020718508961158

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Feedback control is developed for a class of distributed systems described by second-order evolution equations with unbounded observation. In order to increase the degree of stability of the system, a dynamic compensator is designed on the basis of a finite-dimensional model of the system, and a feedback control system is constructed by using sensor outputs. It is shown that the degree of stability of the whole system including the compensator is improved by ‘modal control’ based on a finite-dimensional modal model.

ISSN:0020-7179    

DOI:10.1080/0020718508961159

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The asymptotic properties of the eigenvalues of an optimal closed parabolic system as functions of control weight in the quadratic cost functional are discussed. Boundary control is considered. The results obtained are a generalization of the well-known Kalman theory of finite-dimensional linear systems. The practical importance of the results lies in the fact that they allow us to determine the limit possibilities of control.

ISSN:0020-7179    

DOI:10.1080/0020718508961160

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

A general eigenvalue assignment (EA) control problem for linear multivariable systems is formulated and solved within the framework of parametric eigenstructure assignment. It is shown that EA control is achievable by means of a family of classes of state feedback EA controllers. The number of classes is equal to the number of admissible Jordan forms of the closed-loop system. Each class is characterized by a specific minimum numberNof free parameters (degree of freedom) in the parametric form of the feedback gain matrix. The class of EA controllers with the greatest value ofNis specified. Salient aspects of the method are highlighted in a numerical example.

ISSN:0020-7179    

DOI:10.1080/0020718508961161

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor