摘要:

In this paper the linear transformation which is used in the unified analysis of electrical machines without & commutator is considered. It is shown that, a very straightforward derivation of the so-called commutator transformation is obtained if the underlying mathematical problem is well defined and linear system theory techniques are used to reduce a set of time-varying linear differential equations to a set of time-invariant ones. This leads to a generalization of Park's transformation to an arbitrary polyphase machine, and also yields a better insight into why the usual assumptions of unified machine theory are necessary

ISSN:0020-7179    

DOI:10.1080/00207177208932158

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

This paper discusses the mathematical description of propagation and growth of wave-type phenomena which may occur in many physical systems, such as magneto-hydrodynamic system, fluid flow system, electromagnetic field system. This work also discusses the statement of a maximum principle for this wave generating system, and the problems associated with approximating this distributed system by discretization into lumped systems for the sake of computations. A one-dimensional version of this system with a quadratic cost function has been taken, and the method of gradients and quasilinearization techniques has been applied to derive the optimal control function

ISSN:0020-7179    

DOI:10.1080/00207177208932159

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

This paper extends the analogue solution of initial value hyperbolic equations, as described in an earlier paper (Paul and Ahmad 1970), to equations with split boundary conditions. Solutions obtained on a non-linear flow problem are compared with digital computer solutions and confirm the significant advantage of the analogue machine in respect of computing time. This advantage is of particular relevance to on-line control applications of distributed parameter systems

ISSN:0020-7179    

DOI:10.1080/00207177208932160

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

In Part I, the authors utilized frequency domain techniques to obtain low-order sensitivity models M of m-input, linear, constant, nth-order dynamic systems. The purpose of this paper is to develop a constructive approach for determining the minimal order (ρ) of M. Forsingle-inputsystems it is demonstrated that ρ = n and fornormalsystems ρ = inn. For general systems, tight upper and lower bounds on ρ are provided. These bounds are stated in terms of the system structural properties. Procedures for synthesizing the minimal-order sensitivity models are mentioned. Examples motivate and illustrate both the key ideas and applications of the results.

ISSN:0020-7179    

DOI:10.1080/00207177208932161

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

A second-order method for numerically solving control optimization problems has been developed. The method, referred to as the Modified Sweep Method (MSM), differs from the Successive Sweep Method (SSM) proposed by McReynolds and Bryson (1965) in that the conditions for local control optimality are used to determine the control as an explicit function of the state variables and time. The control is eliminated from the problem and the solution to the resulting two-point boundary value problem can be obtained by linear perturbation methods. The modified sweep method proposed here uncouples the perturbation equations for the state variables and the Lagrange multipliers by using a generalized matrix-Riccati transformation of variables. The resulting algorithm for the numerical iteration process is concerned with determining the initial values of a set of Lagrange multipliers rather than correcting a numerical control programme over the entire time interval of interest. The MSM, therefore, requires less computer storage than the SSM and it is also computationally faster since fewer variables must be integrated. Numerical results are obtained by applying the method to the problem of optimizing the re-entry trajectory of an Apollo-type space-vehicle returning from a lunar mission

ISSN:0020-7179    

DOI:10.1080/00207177208932162

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

Formulae for the differential, with respect to plant parameters of an optimized performance index (performance sensitivity), are extended to include hard (instantaneous) as well as soft (isoperimetric) constraints on the control. In particular, this extends to discontinuous and bang-bang controls the Pagurek-Witscnhausen result on the equality of such differentials for open and closed-loop optimal systems

ISSN:0020-7179    

DOI:10.1080/00207177208932163

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

The estimation of a vector of unknown spatially varying parameters in non-linear partial differential equations from noisy observations is considered. Two algorithms are presented. The first is a method of steepest descent based on consideration of the unknown parameter vector as a control vector. The second is baaed on treating the parameter as an additional state vector and employing least-square filtering. Computational results are presented on the estimation of the diffusivity in the heat equation

ISSN:0020-7179    

DOI:10.1080/00207177208932164

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

Most chemical reactors are multivariable processes and a systematic study of stability and control requires the prior determination of their equilibrium states. This paper shows the multivariable character of such processes by signal flow diagram representation and also presents algorithms for computer determination of the equilibrium states. The chemical reactor chosen is a typical continuous stirred tank reactor with an irreversible, exothermic reaction. Both first and second-order reactions are considered

ISSN:0020-7179    

DOI:10.1080/00207177208932165

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

A simple relationship is shown to hold between two methods which have been suggested for obtaining the least order of a transfer function matrix without determination of a minimal realization

ISSN:0020-7179    

DOI:10.1080/00207177208932166

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

A method of stochastic optimization is presented which enables non-stationary optima to be found. It is based upon the resemblance of basic relations for stochastic and deterministic problems. It is further shown that the method used for determining stationary optima can also be applied for obtaining non-stationary optima, the objective function having been suitably adapted. The relations presented can also servo as a basis for adaptive-seeking algorithms when either the gradient or the restrictions cannot be calculated but nevertheless it is possible to measure their realizations

ISSN:0020-7179    

DOI:10.1080/00207177208932167

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor