摘要:

One of the problems in applying optimal control theory to practical optimal controller design is the need to know all the state variables, a condition which is rarely satisfied. No method is currently available for exactly reconstructing the state variables from the observable variables. In this paper, a method is developed for exact reconstruction of the state variables from the measurable variables.

ISSN:0020-7179    

DOI:10.1080/00207178408933224

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This paper presents a new structure and parameter estimation procedure based on a parametrization obtained from the partial-fraction decomposition of the transfer matrices. The ML method is applied to estimate the parameters. The notation of elementary subsystems (ESS) is introduced, and the structure determination is performed by special rules derived from evaluating the estimated ESS parameters. Examples are shown to illustrate the efficiency of the procedure.

ISSN:0020-7179    

DOI:10.1080/00207178408933225

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Stability analysis is of great significance in those feedback control systems in which the power amplifier is operated as a pulse-modulator device, since under these circumstances the whole control system is highly non-linear. Stability in PWM feedback control systems with a proportional type regulator has been amply described in the literature. Only recently, however, have such studies been extended to include systems with a proportional-plus-integral regulator. In this paper the problem is considered for the case involving a PWM control system, where the regulator is a proportional-plus-integral-plus-derivative, the PWM modulator is of a very general type and the controlled process is of arbitrary order. The stability of the system is analysed by means of a discrete version of the second Lyapunov method ; this method in turn leads to an investigation of the positivity region of a quadratic form defined in the parameter space of the regulator. To improve the stability region obtained, a procedure is investigated whereby only a few parameters of the quadratic Lyapunov function need to be varied. The method proposed has proved extremely simple and flexible to apply, even in cases where the system is of arbitrary order.

ISSN:0020-7179    

DOI:10.1080/00207178408933226

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The use of optimization techniques for the control of drives using a frequency controlled induction motor as an actuator is considered. The approach proposed is based on the choice of a specific control law in the framework of a prefixed class of stabilizing feedback controls. The optimized performance index is obtained aposterioriby applying the Bellmann's principle to a problem with an index in which the term depending on the state is initially unspecified. Successively, the control law is developed, and it is proved how it minimizes a particular index which takes into account both the influence of the error and the control effort. This index has proved very useful in the control choice since it makes it possible to determine a correspondence between the elements of the weighting matrices and the system transient behaviour.

ISSN:0020-7179    

DOI:10.1080/00207178408933227

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This paper considers the set (℘) of all solutions of a quadratic matrix inequality (QMI) that arises in the discrete-time stochastic realization theory and the subset (℘0) of all solutions of the corresponding algebraic Ricatti equation (ARE). A complete characterization of some subsets of ℘ and ℘0is given. The boundary, interior and extreme points of ℘ are identified. It is shown that elements of ℘0are not only boundary points of the convex compact set ℘, but are extreme points as well.

ISSN:0020-7179    

DOI:10.1080/00207178408933228

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This paper presents results from a study to examine the stabilization properties of linear time delay systems and systems depending on a parameter using techniques associated with the algebraic Riccati equation (ARE). These classes of systems can be viewed as members of a broader class of systems called generalized linear systems (GLS). Techniques of spectral factorization for the GLS play an essential role in the methods for performing this stabilization. Necessary and sufficient conditions for the existence of a polynomial solution to the generalized ARE are derived. Numerical examples are given in order to illustrate and clarify the results.

ISSN:0020-7179    

DOI:10.1080/00207178408933229

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A new concept of the unknown input observability, namely(r, s ; K)observability, for discrete-time linear multivariable systems is introduced. This concept is an extension of the conventional unknown input observability and reconstructibility. Necessary and sufficient conditions for the(r, s ; K)observability of the given system are derived by introducing a new unobservable subspace and presenting algorithms for obtaining the subspace. It is also shown that these new concepts are closely related to the existence condition of a dead-beat observer for a decentralized control system.

ISSN:0020-7179    

DOI:10.1080/00207178408933230

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A bang-bang control law is presented for use in three axis gas jet attitude control systems where precise pointing is required within stringent mass and power limitations. A switching boundary similar to the time optimal one for a double integrator adapts to a disturbance acceleration estimate, a fixed magnitude offset from the phase plane origin being changed in sign whenever the boundary is crossed. The latter feature facilitates optimal acquisition of the ideal limit cycle of preset amplitude, the number of thruster operations being automatically minimized to prolong valve life. In order to render performance largely independent of the iteration period of the microprocessor or digital computer assumed for implementation, at least two successive switching times of the desired control function are predicted, being signed to include the sense of control to be applied. The control law is able to function in the presence of disturbance torques ranging in magnitude from a small fraction of the available control torque to values actually approaching the control torque. The control law is intended to be complemented by a state estimator providing estimates of the disturbance acceleration, body rate and pointing error.

ISSN:0020-7179    

DOI:10.1080/00207178408933231

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

An efficient technique is presented for the evaluation of cost integrals for systems with delay in either feedback or forward paths. Closed form results in terms of system transfer function parameters are given for some systems of low order as examples of the application of the technique.

ISSN:0020-7179    

DOI:10.1080/00207178408933232

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

This paper presents a necessary and sufficient condition for finite spectrum assignability of systems with multiple commensurate delays in both states and control. A systematic design procedure of the control law is presented. The important point of the proposed method is that finite spectrum assignment can be accomplished without any extra integrators, in contrast to the suggestion given by Manitius and Olbrot (1979).

ISSN:0020-7179    

DOI:10.1080/00207178408933233

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor