摘要:

It is demonstrated that, for the best results, the Smith predictor need not necessarily be designed to eliminate time delay of a lumped-parameter process completely from the closed-loop characteristic equation. It is shown how this feature can advantageously be employed in a linear-predictor control of linear parameter-distributed processes containing in their transfer function term exp [-√(as2+bs+c)] which cannot be eliminated completely by a physically realizable predictor. Detailed analytical solution of the characteristic equation is given, for a heat-diffusion process compensated by an idealized form of the linear predictor. Digital simulation is then used to demonstrate how a particular rational approximation to this idealized predictor can improve the closed-loop system dynamic behaviour. Both set-point and load step changes are considered.

ISSN:0020-7179    

DOI:10.1080/00207177908922766

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

This paper gives bounds for the inverse transfer function.between thejth input-output pair in ann×nmultivariable feedback system when thejth loop is open and all other loopsk≠jare closed. Choice of the minimal such bounds are also studied as well as the effect of feedback gains on these bounds. These results are useful in the design of linear multi variable systems.

ISSN:0020-7179    

DOI:10.1080/00207177908922767

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The paper deals with optimal adaptive systems using quadratic criterion functions. The synthesis of the optimal control vector of parameter adaptive systems is based on the substitution of process matrices in the linear regulator with their estimates, obtained from an identification procedure. The optimal control vector of model reference systems is determined using the maximum principle. The identification procedure in the case of parameter adaptive systems and the synthesis of model reference systems are both based on the use of Lyapunov functions. The mathematical operations for transformation of the Riccati-type differential equation and optimal control vector of model reference systems into the form of classical Kalman-type feedback systems are determined. Using these operations optimal model reference systems can be transformed into parameter adaptive systems. The conditions for the reverse transformation are also given. It is shown, that both approaches lead to the same regulator structure.

ISSN:0020-7179    

DOI:10.1080/00207177908922768

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

This paper considers the poles and zeros of a rational matrix, particularly those situated at infinity. Certain results are established which are generalizations of the rational function case, and several connections are made with previous work.

ISSN:0020-7179    

DOI:10.1080/00207177908922769

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The problem of finite time controllability of linear time invariant systems by piecewise constant output feedback is considered. It is shown that complete controllability and complete observability are both necessary and sufficient conditions for output feedback controllability by piecewise constant gain. Dead-beat output feedback controllers that drives the system to the origin in at most (μd×vd) steps, are also presented, where μdandvgare the indices of controllability and observability.

ISSN:0020-7179    

DOI:10.1080/00207177908922770

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

For an irreducible polynomial system matrix P(s)= ((1970, p. 111) has shown that thepolarstructure of the associated transfer function R(s)=V(s)T−2(s)U(s)at any finite frequency is isomorphic to the zero structure ofT(s) at that frequency, while the zero structure ofR(s) at any finite frequency is isomorphic to that ofP(s) at the same frequency. In this paper we obtain the appropriate extensions for the structure atinfinite frequenciesin the particular case of systems for whichT(a) =.sE− A (withEpossibly singular),U(s) = B,V(s) = C, andW(a) =D, under a strengthened irreducibility condition. We term such systemsgeneralized state-space systems, and note that any rationalR(s) may bo realized in this form. We also demonstrate in this case that a minimal basis (in the sense of Forney (1975) for the left or right null space ofP(s) directly generates one with the same minimal indices for the corresponding null space of R(s), and vice versa. These results also enable us to identify the pole-zero excess ofR(s) as being equal to the sum of the minimal indices of its null spaces. Connections with Kronecker's theory of matrix pencils are made.

ISSN:0020-7179    

DOI:10.1080/00207177908922771

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The problem of constructing minimal-order inverses for linear, time-invariant systems with zero as well as arbitrary initial states is considered, and an algorithm which uses only simple matrix operations is presented for constructing these inverses. It is shown that, for a system described by the 4-tuple (A, B, C, D), a minimal-order inverse has dynamical order equal to the dimension of the maximal output-nulling invariant subspace of the state space of the system ; and in the case of a system with arbitrary initial states, this is identically zero.

ISSN:0020-7179    

DOI:10.1080/00207177908922772

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The problem of the decentralized control of a linear interconnected dynamical system is considered. This is done by defining the problems of the decentralized controllability and of the decentralized observability, which are solved for a system consisting of two interconnected scalar systems. The solution is determined using the theory of the linear dynamical systems in the differential operator representation (Wolovich 1974), and provides, besides structural results, a systematic method for the decentralized control of these systems.

ISSN:0020-7179    

DOI:10.1080/00207177908922773

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Reduced order models of high-order single-input single-output dynamical systems are derived in terms of beat Chebyshev rational approximations on a desired domain in the complex plane. An algorithm is proposed for deriving local best Chebyshev rational approximations for a complex function in the complex plane and is based on a complex version of Lawson's algorithm. The method is applied to minimizing a time response error bound of the reduced models and it is shown that the local best Chebyshev approximations are in fact frequency-response approximations. The algorithm enables the control of the rational approximation pole and zero locations and, therefore, if the given system is stable, its reduced order models can be made stable as well as minimal phase.

ISSN:0020-7179    

DOI:10.1080/00207177908922774

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Structural indices and state feedback of finite dimensional linear systems are analysed with the help of elementary module theory. The basic modules are polynomial and have a natural graduation. With respect to this graduation the concepts of minimal bases and degree preserving isomorphisms are introduced. Thus it becomes possible to give a module theoretic interpretation of the different definitions of structural indices. They are reduced to invariants of a special submodule ofKm[s] which is also crucial for the understanding of Brunovsky-transformations. It is shown that the Brunovsky-transformations induce families of degree-preserving module isomorphisms. A detailed study of this fact leads to results concerning pole assignment via state feedback, classification of orbits of the Brunovsky-group and canonical forms.

ISSN:0020-7179    

DOI:10.1080/00207177908922775

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor