摘要:

A variable-structure control system (VSS) for single-input systems is investigated. It is shown that the design of VSS control is similar to that of modal synthesis and can be treated as such if the feedback gains are not switched. The case of reduced-order switching VSS control is investigated where not all states are available for switching function synthesis or control. A second-order example and a third-order example are given with time responses and state trajectories.

DOI:10.1049/ip-d.1983.0007

出版商:IEE    

年代:1983

数据来源: IET

摘要:

The paper describes a proposed new type of extended-range angular pick-off which has characteristics that could prove superior in certain respects to existing devices. AC rotary pick-offs currently being manufactured have a linear output voltage over an angular range of 70°. The object of the work is to design and construct a prototype pick-off which has a linear output voltage over an angular range of 90°. The extended range of linearity is achieved by two offset concentric excitation windings and an offset rotor, giving a constant mutual flux over a range of 90° of rotor angle relative to the stator. The paper is mainly concerned with the design, construction and testing of the prototype pick-off. It is felt that this pick-off has successfully achieved its objectives and can be a very useful addition to the present-day limited-range pick-offs.

DOI:10.1049/ip-d.1983.0008

出版商:IEE    

年代:1983

数据来源: IET

摘要:

Controller design for scalar or multivariable systems whose models are unknown or highly complex are frequently based in practice on the use of a highly simplified approximate plant model. In such circumstances it is vital to be able to quantify the degree of uncertainty to be expected from the use of such a model for prediction of closed-loop characteristics. It is shown how frequency-domain design techniques can be simply extended to incorporate information deduced from the observed differences between open-loop plant and the approximate model step response to quantify this uncertainty and, in particular, to guarantee closed-loop stability and tracking of step demands. A modification of this analysis also yields the possibility of bounding the error in prediction of closed-loop transient performance. The approaches are all graphical in nature and are easily implemented in an interactive computer-aided-design mode.

DOI:10.1049/ip-d.1983.0009

出版商:IEE    

年代:1983

数据来源: IET

摘要:

The paper deals with the nonlinear adaptive stabilisation of a class of continuous linear large-scale interconnected systems. The presented new approach combines previously known linear and new non-linear stabilisation features. Systems subject to a class of external perturbations are also considered. Sufficient conditions of stability are derived using the notion of eventual stability. The results are illustrated numerically.

DOI:10.1049/ip-d.1983.0010

出版商:IEE    

年代:1983

数据来源: IET

摘要:

A set of sufficient conditions for a robust control of a nonlinear process consisting of memoryless time-varying nonlinearities is obtained by extending the results of the linear servomechanism problem. The robust controller consists of an error-driven servocompensator, containing the modes of all the endogenous (system states) and exogenous (reference and disturbance) signals present in the system, and a stabiliser.

DOI:10.1049/ip-d.1983.0011

出版商:IEE    

年代:1983

数据来源: IET

摘要:

The dominance concept has proved of great value in multivariable design; essentially providing a condition which allows design on a single-input single-output basis. It also plays a key role in construction and analysis of iterative procedures for solving sets of linear equations. Three practical steps for achieving dominant transfer function matrices are discussed together with three classes of algorithms capable of solving relatively large problems and yielding solutions which are ‘optimal’ in a natural sense. The algorithms discussed solve:(i) optimum permutation of plant input-output relationships(ii) optimal scaling of plant variables(iii) construction of ‘real’ precompensation

DOI:10.1049/ip-d.1983.0013

出版商:IEE    

年代:1983

数据来源: IET

摘要:

Interaction introduced by the chassis structure of a magnetically suspended vehicle can deteriorate the performance of the suspension controllers. The paper presents a comparison between two particularly simple chassis structures and the design constraints introduced by misaligned tracks.

DOI:10.1049/ip-d.1983.0015

出版商:IEE    

年代:1983

数据来源: IET