摘要:

In parallel manner to a previous paper on continuous systems, stability analysis is made of single-loop, sampled-data, time-delay systems wherein the plant consists of a delay element in combination with a pure gain, a single integration or a double integration. The sampled-data controller is considered in turn to be of proportional, simple lead or simple lag characteristics; the method is extendable to other systems of relatively low order. Analysis is taken only to the extent allowed by the solution of relatively simple polynomial equations derived from the characteristic equation in thez-domain. The resulting catalogue of results is offered as compact information not previously available in this form.

ISSN:0020-7179    

DOI:10.1080/00207177108932011

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A ‘small-gain’ theorem is derived concerning theL1∩Lpstability of a stable IPFM system,p∈[1,∞] The development of the theorem through familiar functional analysis techniques is rendered possible after a formulation of the input-output relation of the pulse modulator is established.

ISSN:0020-7179    

DOI:10.1080/00207177108932012

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

This paper introduces a technique for the synthesis of optimal sample-data systems with constrained control variables. The performance index is chosen to be of integral form so that the system errors between sampling instants are accounted for as well as the errors at the sampling instants. Both time-varying and stationary systems are considered. The development of the synthesis technique is based upon an extended maximum principle and the variation method. The result of the synthesis may be implemented by a closed-loop non-linear discrete-time system or a closed-loop nonlinear sampling system without on-line computation. A numerical example is given. The technique presented in this paper can be extended to synthesize the optimal control of multi-rate, variable-rate or staggered sampled-data systems.

ISSN:0020-7179    

DOI:10.1080/00207177108932013

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

This investigation is concerned with the optimal control of unknown, time-invariant. linear discrete systems. Of particular interest is the relationship among the identification problem, the specification of the control law assuming the system is known and the overall optimalizing control. For single-stage control with noiseless observations, conditions under which the use of separate identification and control procedures results in overall optimal control are established. The complexity inherent in the control problem is illustrated with a simple single-stage example wherein optimal control calls for filtering of the observed data by a time-varying, data-dependent operator, for which no simple recursive implementation exists.

ISSN:0020-7179    

DOI:10.1080/00207177108932014

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A coupling perturbation method is developed for near optimum design of non-linear systems. A scalar parameter ϵ is introduced in annth-order system such that for ϵ ϵ = the system decouples into two (or more) independent low-order sub-systems. By the same procedure ϵ is introduced into the performance index. The near optimal controlu¯is defined as a truncated power series in ϵ. It is shown that each term of the above series can be sequentially obtained by separate sub-system calculations. Thus a considerable saving in computational effort is achieved

ISSN:0020-7179    

DOI:10.1080/00207177108932015

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Quasi-stationary switching boundary in the case of time-optimal control of third-order systems is dealt with in this paper. Time-optimal switching boundaries are derived for servomechanism-type systems for two types of pole locations. In each case the input to be applied after the optimal timeT*in order that the system follows the reference input is also calculated.

ISSN:0020-7179    

DOI:10.1080/00207177108932016

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The asymptotic behaviour is studied of feedback systems which are described by time-varying or nonlinear differential-difference equations. Frequency-domain criteria are obtained using Liapunov functionals which are denned as path-independent line integrals in function space. They constitute an extension to distributional convolution equations of well-known results for ordinary differential equations.

ISSN:0020-7179    

DOI:10.1080/00207177108932017

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The stochastic bang-bang control problem of maximizing the expectation of the first passage time of the state to the boundary of a certain safe region is considered. It is assumed that the dynamics of the system is described by a linear stochastic differential equation. By use of dynamic programming, the problem is reduced to a boundary-value problem of Dirichlet type for the Bellman equation. A difference scheme is applied in order to obtain the numerical solution of the boundary-value problem. It is found that for first-order systems the difference scheme gives excellent numerical results. Some switching curves are also obtained for a second-order plant l/s2with additive Gaussian white noises.

ISSN:0020-7179    

DOI:10.1080/00207177108932018

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A method of obtaining estimates of the parameters of the pulse transfer function of linear systems is described for the situation where a pseudorandom binary sequence test signal is used. The technique used is essentially an extension of the instrumental variable method described in the literature and involves the use of time-weighted pseudorandom binary sequences to improve the estimates in the presence of random disturbances

ISSN:0020-7179    

DOI:10.1080/00207177108932019

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A new method has been presented for the determination of a low-order model approximating a high-order system. It is based on the use of the matrix pseudo-inverse to estimate the parameters of the model which minimize the sum of the squares of the errors between the response of the actual system and that of the model at the sampling instants. One of the advantages of this method is that the description of the actual system dynamics need not be known, but only the measurements of the input-output data are required. As the algorithms are iterative, computation is fairly straightforward, and the requirement for storage of input-output data depends only on the order of the assumed model, not on the number of iterations in the interval considered for minimization. An example of the application of the method for the determination of an approximate second-order model of a seventh-order system has been given, and compared with the reduced model obtained using another method.

ISSN:0020-7179    

DOI:10.1080/00207177108932020

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor