摘要:

The closed-loop optimal control of a singularly perturbed linear system, with free-end-point conditions, gives rise to a matrix Riccati equation. A singular perturbation method is developed to analyse the Riccati equation. An algorithm is presented to indicate the sequence of steps involved in the actual application of the method for obtaining the zeroth-first- and second-order approximations. An example5,6,9is provided to illustrate the method.

DOI:10.1049/ip-d.1980.0001

出版商:IEE    

年代:1980

数据来源: IET

摘要:

Improvements in control strategy for steam temperature have been made at Fawley power station because of the changing emphasis, from base-load to load-following, and to two-shift operation. Saturation protection is included to prevent tube waterlogging; although the principle is well established, the implementation is superior to some others. A new valve characteristic is recommended, although, as a temporary expedient, gain adaption has been used to emulate the desired characteristic. Finally, the slow dynamics of the final temperature control are countered by a predictive calculation, backed up by a feedback trim. Experimental results are presented, and a suggestion is made for a further improvement in the predictive calculation, suitable for a digital implementation.

DOI:10.1049/ip-d.1980.0002

出版商:IEE    

年代:1980

数据来源: IET

摘要:

This paper presents a self-tuning controller that minimises a cost function incorporating system input, output and set-point variations, and adapts it in such a way that the closed-loop poles are located on prespecified locations. The link that exists between the classical control strategy of pole assignment and the suboptimal strategy of the self-tuning controller is demonstrated and made use of to produce a generalised controller which possesses the major advantages of both. The controller combines the robustness of pole assignment with the ease of reference following provided by suboptimal self tuning.

DOI:10.1049/ip-d.1980.0003

出版商:IEE    

年代:1980

数据来源: IET

摘要:

A new block-Routh array with block-Routh algorithm is developed to extract the greatest common matrix polynomial of two matrix polynomials that are not coprime, and to construct a block-transformation matrix that transforms a block-state equation from a block-companion form to a block-tridiagonal form. The newly developed block-state equation in the block-tridiagonal form is a minimal realisation of a matrix-transfer function. Also, the block-state equation is used to synthesise a driving-point impedance matrix. A stability criterion is then derived to test the stability of a class of matrix transfer functions.

DOI:10.1049/ip-d.1980.0004

出版商:IEE    

年代:1980

数据来源: IET

摘要:

A convenient technique for placing some poles while preserving others is to use state feedback with unity-rank controllers. The paper discusses the problem of reducing the required control effort by considering the minimisation of a matrix functional whose value reflects the magnitudes of the elements of the feedback gain matrix. The investigation proceeds with vector-analysis methods, and it is shown that solutions can be obtained in closed form without recourse to numerical optimisation techniques. The algorithms are developed for use in a recursive scheme for placing several poles. A well established algorithm for constructing feedback controllers for pole placement preserves the acceptable modes by making use of the concept of unobservability. A proposed extension to this scheme is that of preserving modes by making use of the dual concept of uncontrollability, and it is shown that further substantial reductions in control effort can be made by the use of this generalisation.

DOI:10.1049/ip-d.1980.0005

出版商:IEE    

年代:1980

数据来源: IET