摘要:

In this paper it is shown that a number of ambiguous points arising in transient stability analysis of power systems can be clarified if partial or output stability concepts are used instead of stato stability. This solves the question of the number of state variables and the validity of using positive semi-definite Lyapunov functions. It is further discussed how a very general Lur'e-type Lyapunov function can be derived for the power system stability problem, which unifies and generalizes numerous Lyapunov functions available in the technical literature.

ISSN:0020-7179    

DOI:10.1080/00207177408932606

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The problem of obtaining output feedback gains to minimize a quadratic performance criterion which includes sensitivity variables is discussed. The equivalent stochastic problems are also studied and when a Kalman filter is allowed, the minimum variance estimate of the state is employed to implement the control. A set of non-linear matrix equations are obtained which constitute the necessary conditions that must be satisfied for an optimal solution. For the deterministic case it is shown that when no sensitivity is considered and the matrix which relates output and input is invertible, the usual Riccati formulation is obtained. The problem is also reformulated using a compensator and it is shown that it can be cast into an instantaneous feedback form.

ISSN:0020-7179    

DOI:10.1080/00207177408932607

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

A discrete complementary variational principle is developed and applied to linear and non-linear discrete-time optimal control systems. Using the variational approach, a primal-dual relationship is established. This relationship provides a precise measure of system suboptimality independent of anya prioriknowledge of the optimal solution.

ISSN:0020-7179    

DOI:10.1080/00207177408932608

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

It is shown that a Routh-type array can be applied to the problem of location of zeros of a real polynomial with respect to the unit disc. This is done by obtaining new half-order expressions for the Schur-Cohn determinants. The work is complementary to that in a previous paper in which it was shown that a generalization of the Jury array can be similarly applied to the continuous-time linear system stability problem.

ISSN:0020-7179    

DOI:10.1080/00207177408932609

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The controllability properties of the sensitivity system are shown to play an essential role in a number of control problems. By thoroughly analysing the Jordan canonical form of the sensitivity system, the condition is obtained that such a system is uncontrollable whenever the number of parameters is greater than the number of control variables.

ISSN:0020-7179    

DOI:10.1080/00207177408932610

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

This paper considers a class of multivariable, non-linear time-varying feedback systems with an unstable convolution subsystem as feedforward and a time-varying non-linear gain as feedback. The impulse response of the convolution subsystem is the sum of (i) a finite number of increasing exponentials multiplied by non-negative powers of the timet, (ii) a term that is absolutely integrable and (iii) an infinite series of delayed impulses. The main result of the paper is theorem 1. It essentially states that (i) if the unstable convolution subsystem can be stabilized by a constant feedback gainFand (ii) if the incremental gain of the difference between the nonlinear gain function andFis sufficiently small, then the non-linear system isLpinstable for anypε[l, ∞]; furthermore, the solutions of the non-linear system depend continuously on the inputs in anyLp-norm. The fixed point theorem is crucial in deriving the above theorem.

ISSN:0020-7179    

DOI:10.1080/00207177408932611

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The stability problem for distributed parameter energy systems governed by a set of nonlinear, parabolic, partial differential equations is treated by the method of comparison theorems. Sufficient conditions for asymptotic stability are presented in terms of the system parameters. The example of a system with temperature control is also presented.

ISSN:0020-7179    

DOI:10.1080/00207177408932612

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

A second-order control system with a saturating controller and a random disturbance is investigated. It is known that when the control signal preceding the saturator is a linear combination of state coordinates, the steady-state probability density in state space may be obtained by solution of the Fokker-Planck equation. In the present note it is shown that when the mean-square-error is minimized the saturator operates as a relay ; and the optimal parameter of the switching line is calculated. The explicit results obtained make the system a useful test case for computational solutions of the Fokker-Planck equation, and in other investigations of non-linear stochastic control systems.

ISSN:0020-7179    

DOI:10.1080/00207177408932613

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Conditions under which the asymptotic stabilization of uniformly decoupled time-varying multivariate systems is possible are explored. This is accomplished by developing a canonical form for integrator uniformly decoupled system in which the coefficient matrices have a simple structure. The procedures developed rely on certain conditions on the given system and yield explicit expressions for the stabilization compensators.

ISSN:0020-7179    

DOI:10.1080/00207177408932614

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The accuracy of the Guillemin transfer function model is analysed; an arbitrary degree of precision can be achieved by proper choice of the approximation segments applied to transient response. The technique is also attractive for non-linear systems with low-pass filter specifications. A singular Guillemin model is also discussed.

ISSN:0020-7179    

DOI:10.1080/00207177408932615

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor