摘要:

Conditions for loeal optimality are worked out using simple calculus of variations. To find the optimum control, a two-point boundary value problem in space and time has to be solved, which involves the solution of the adjoint differential equation together with the prooess equation. The method is applied to the optimization of a periodic process, consisting of a tubular reactor where a second-order homogeneous reaction takes place and a periodicity oondition of the state is satisfied everywhere along the reactor. Tho plug flow and the diffusion model are assumed. In the first case an exact solution is carried out. The improvements in yield compared with steady-state conditions are obtained and shown in graphs.

ISSN:0020-7179    

DOI:10.1080/00207176908905864

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The paper shows how the general shape of the root–locus of a four polo system is related to the relative positions of its open loop poles. The various forms of the locus are displayed on two maps. One map shows the loci of systems having two or four real open loop poles while the second map deals with the case of two pairs of complex poles. For each general shape of the locus analytical expressions are given for real axis break points, imaginary axis crossings, and maximum gain consistent with closed loop stability.

ISSN:0020-7179    

DOI:10.1080/00207176908905865

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

A successive approximation technique based on statistical linearization is developed which permits the design of sub–optimal linear controls for non–linear time–invariant processes perturbed by Gaussian random disturbances. The application of the technique to a chemical process example is given, and the validity of the results is confirmed by simulation.

ISSN:0020-7179    

DOI:10.1080/00207176908905866

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

Convergence properties of a perturbational procedure for generating sub–optimal control laws for non–linear dynamical systems described by x = Ax + ∈φ(∈, x)+ Bu are discussed. Optimization is carried out with respect to a quadratic performance index, and an estimate of the degradation of performance resulting from truncation of the perturbational solution is presented.

ISSN:0020-7179    

DOI:10.1080/00207176908905867

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

For a given system, the insensitivity approach is to seek a region within which para-motors or functions may lie so that some property of the solution is unaltered by (i.e. is completely insensitive to) such variations provided they lie within the determined region. For optimal control systems a set of finite changes are found which leave the optimal control (as a function of state variables and time) unaltered. A now result is given for the general non-linear case and is unified with earlier work on optimal linear systems, and on stable systems where the problem is to find finite disturbances which do not affect the stability behaviour.

ISSN:0020-7179    

DOI:10.1080/00207176908905868

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

Methods due to Undrill and to Burnett and Storey for calculating MacFarlane's generalized functional matrix are critically compared. A comparison is also made with a method of Bass and Webber for finding the optimal feedback control in the case of linear systems with higher than quadratic indices.

ISSN:0020-7179    

DOI:10.1080/00207176908905869

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The results of a numerical investigation of a number of techniques for stability analysis of non-linear systems are presented. The methods compared are the Ingwerson and Zubov procedures for construction of Liapounov functions, a number of methods for obtaining optimum Liapounov functions, tracking functions, the alternating extreme radius path, and the method of Luus and Lapidus.

ISSN:0020-7179    

DOI:10.1080/00207176908905870

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

Exact and approximate methods of determination of limit cycles in a relay control system including an actuator with PI transfer function and limited output are given. No restrictions are imposed on the order of the plant transfer function. The stability of the limit cycles may be checked using one of the well-known methods, using the describing function concept. With the help of an example it is indicated that the methods suggested give reliable results in eases where the use of the conventional describing function fails.

ISSN:0020-7179    

DOI:10.1080/00207176908905871

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

An algorithm is presented for solving the algebraic matrix Riccati equation using the Fletcher-Powell reformulation of Davidon's method of function minimization. The function to be minimized, as well as its gradient vector required by the minimization process, are evaluated in closed-form, thereby preserving the simplicity and stability properties of the minimization procedure. The quadratic convergence of the algorithm is not dependent on the initial choice of the approximate solution.

ISSN:0020-7179    

DOI:10.1080/00207176908905872

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor