摘要:

In this paper the computational complexities hitherto associated with the sequential synthesis of modal control policies for multi-input continuous-time systems are removed by the presentation of a set of new results concerning the eigenstructure of sequentially synthesized multi-input systems. The resulting design procedure is illustrated by considering a numerical example involving a sixth-order system with three control inputs.

ISSN:0020-7179    

DOI:10.1080/00207177708922248

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

If a continuous strong Markov process is exponentially stable w.p.l., then there exists a Lyapunov function which satisfies an exponential inequality along the process. An analogous result is also true for discrete-time processes, but requires a different construction for the Lyapunov function. This is in contrast to the case of asymptotic stability w.p.l. for which the same construction is valid for both continuous and discrete-time processes.

ISSN:0020-7179    

DOI:10.1080/00207177708922249

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

This paper deals with the design of fixed-order dynamic compensators for non-stationary linear stochastic systems with noisy observations, where the observation noise need not necessarily be white. An integral quadratic performance index defined over a finite time interval is employed and this yields a matrix variational problem in the compensator parameters. It is shown how the optimal, possibly time-varying, compensator parameters rnay be determined by direct solution of this variational problem using a conjugate-gradient technique. Consideration is also given to finding suboptimal compensators that are simpler to implement. In particular, an algorithm is proposed for designing compensators having gains that are constrained to be piecewise-constant functions of time, with provision for optimally choosing the instants at which gains changes occur. An illustrative numerical example is included.

ISSN:0020-7179    

DOI:10.1080/00207177708922250

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A unified approach to multilevel control and optimization of interactive dynamic systems based on the generalized gradients technique is fully analysed. Through this approach the variables involved are divided into two basic distinct sets : a dependent set which is handled on the first level and an independent set which is manipulated on the second level of the proposed structure. Depending on the choice of both sets of variables several two-level structures could result. An appropriate candidate is thus selected in which the co-state variables are updated successfully at the coordination level. The developed structure possesses the principal advantages of solution feasibility, avoiding singular arcs and bypassing the difficulties of two-point boundary value problems.

ISSN:0020-7179    

DOI:10.1080/00207177708922251

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

This paper considers the problem of optimal control for systems which are linear in control but non-linear in state. It is shown that there is a large class of control systems in which optimal singular trajectories are allowed to lie only on a certain hypersurface when a condition similar to the normality condition for linear time-optimal control systems is fulfilled. Furthermore, under the same condition, it is proved that the optimal control becomes totally bang-bang or totally singular. A necessary and sufficient condition for the optimality of these singular solutions is established. It should be noted that such a hypersurface cannot be defined when the system is linear. Finally an example is given to show that the results obtained can no longer be valid for a slightly wider class of optimal control systems.

ISSN:0020-7179    

DOI:10.1080/00207177708922252

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A quantitative technique is presented for determining the existence and uniqueness of simple limit cycles in autonomous relay control systems. In addition, the technique gives bounds on the error resulting from the use of an approximate limit cycle analysis method. The technique here is based on the contraction mapping fixed-point theorem. The intention of this work is to provide an organized procedure for studying error-bound problems in relay control systems in which any computations are as transparent as possible. The results presented here are general in the sense that they may be applied to any approximate analysis, including but not limited to the describing function, in which the relay characteristic may be frequency dependent.

ISSN:0020-7179    

DOI:10.1080/00207177708922253

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The paper outlines a modified multivariable frequency-response approach to design which takes advantage of the particular characteristics and control requirements of a power-station. The usual design aim of achieving low interaction levels following disturbances in any loop is relaxed to one where low interaction is required following a disturbance in only one loop, leading to improved power-response performance by means of a simpler controller and design procedure.

ISSN:0020-7179    

DOI:10.1080/00207177708922254

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

In this paper the concept of recoverability is developed and a criterion for recoverability is presented in the case of constant linear systems. A second-order process with control component failure is studied and control strategies for the choice of various performance indices are determined. The time-optimality of the resulting trajectories for certain values of the time of component failure is demonstrated.

ISSN:0020-7179    

DOI:10.1080/00207177708922255

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A scalar polynomial expression in the scalar feedback gain, that is used to evaluate the root-loci of a linear multivariable system, is derived. It is shown that the set of values of the scalar gain for which the root-loci intersect the imaginary axis (excluding the origin) is a subset of these polynomial roots.

ISSN:0020-7179    

DOI:10.1080/00207177708922256

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Frequency-domain design of feedback systems for prescribed insensitivity of response to parameter variation has relied, in the past, on trial-and-error methods of translating sensitivity specifications from time domain to frequency domain. A rational method for such translation is introduced, which enables time-domain specifications to be achieved by known methods of frequency-domain design.

ISSN:0020-7179    

DOI:10.1080/00207177708922257

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor