摘要:

A design of reduced-order observers is proposed for linear time-invariant systems with unknown inputs including unknown measurement disturbances. Based on the unknown-input observer design, a systematic treatment of designing fault detection and isolation (FDI) observers is provided. The core of the FDI observer design is to find an observable subsystem where the faults of interest show up and the rest of the faults disappear. The FDI observer design procedure has a clear physical meaning. Robust FDI observers for uncertain systems can also be obtained using the FDI observer design provided the uncertainties of the system can be formulated as unknown inputs. It is shown that the parity equations of another important FDI method can be generated in an elegant way using a dead-beat FDI observer scheme directly in the time domain. Examples are included to show some concepts and to illustrate the FDI observer design method.

ISSN:0020-7179    

DOI:10.1080/00207179408921497

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

A non-parametric method for controller synthesis developed earlier is extended to non-minimum-phase (NMP) plants represented by non-parametric impulse response (IR) models. The authors are not aware of the existence of other non-parametric design techniques for NMP plants. The proposed method borrows ideas from Predictive Control, and its effectiveness is confirmed by design examples.

ISSN:0020-7179    

DOI:10.1080/00207179408921498

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

In his 1868 paper on governors, Maxwell gave an analysis of the hydraulic-brake governor devised by William Siemens. The present paper attempts to elucidate and fill out Maxwell's treatment, which was brief and enigmatic.

ISSN:0020-7179    

DOI:10.1080/00207179408921499

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Early and current self-tuning algorithm formulations were generally based on the assumption that the process model under investigation is linear within a certain operating point. A standard Recursive Least-Squares (RLS) estimation algorithm was used to update the model parameters whose data input and output were normally fed through a filter with adequate characteristics. One of the most popular themes belonging to this class of adaptive controllers is that of generalized predictive control (GPC). Classified in the category of long-range predictive controllers (LRPC) its control law stems from the minimization of a cost function over a horizon which spans that used by the RLS algorithm (one step ahead). This paper describes a new approach which derives the same model parameters using extra filtering provided by an identification objective similar to the one used for control derivation. Already successfully applied in real-time to a SISO control system by its original authors, the scheme, known as long-range predictive identification (LRPI), is applied here to a nonlinear multivariable anaesthetic model in combination with generalized predictive control with feedforward (GPCF) and multivariable GPC using a P-canonical form for the process model, and its performance is assessed.

ISSN:0020-7179    

DOI:10.1080/00207179408921500

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

In this paper we make explicit connections between classical absolute stability theory and modern mixed-μanalysis and synthesis. Specifically, using the parameter-dependent Lyapunov function framework of Haddad and Bernstein and the frequency dependent off-axis circle interpretation of How and Hall, we extend previous work on absolute stability theory for monotonic and odd monotonic nonlinearities to provide tight approximations for constant real parameter uncertainty. An immediate application of this framework is the generalization and reformulation of mixed-μanalysis and synthesis in terms of Lyapunov functions and Riccati equations. This observation is exploited to provide robust, reduced-order controller synthesis while avoiding the standardD, N - Kiteration and curve-fitting procedures.

ISSN:0020-7179    

DOI:10.1080/00207179408921501

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

A Predictive Proportional + Integral (PPI) controller with improved performance over standard PI and PID controllers is proposed. This controller consists of two parts: a standard PI controller and a predictive term with which its dynamics depend on the system time delay. The controller is realized by a continuous time implementation; i.e. a numerical solution of differential equations rather than a transformation to the Z-domain. The performance of this controller is compared with that of the PID controller tuned by Zeigler and Nichols and three other recent methods of tuning PID controllers. The conditions for stability are derived and the sensitivity of the new controller to process parameter changes is analysed by Monte-Carlo evaluation.

ISSN:0020-7179    

DOI:10.1080/00207179408921502

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

This paper discusses the role and the relationships among three coupled diophantine polynomial equations involved in the solution of the optimal continuous-time LQ regulation problem. The emphasis is on establishing conditions under which the LQ regulator can be obtained via the solution of a single uncoupled diophantine equation. This analysis is motivated by the fact that, although recent papers have clarified the matter for the discrete-time domain, some subtle differences exist in the continuous-time domain. As a consequence, the extension of the discrete-time results to the continuous-time context requires a deeper analysis, which is the main aim of this paper.

ISSN:0020-7179    

DOI:10.1080/00207179408921503

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

This paper describes a set of piecewise constant waveforms which, when used as the method of dispatch of power to a first-order system, offers distinct advantages over other piecewise constant signal methods. The waveforms are similar to those which are produced by binary rate multipliers and the technique is called ‘Binary Rate Modulation’. The stability of the resulting discrete closed loop system is investigated using a circle criterion adaptation, applied to a multiple nonlinearity, with a multiple pulse output in each nonlinearity and by a proposed ultimate linear technique. The gains for asymptotic stability and limit cycling are found from the techniques. Results in accordance with the predicted values are obtained from observed system responses. The two stability techniques can be easily applied to systems using pulse width or pulse frequency modulation output drives to first-order systems.

ISSN:0020-7179    

DOI:10.1080/00207179408921504

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

This paper is concerned with the minimization of a given quadratic functional for time-invariant, controllable linear systems with the constraint that another quadratic functional (the ‘output energy’) assumes a given value. It is shown that (under certain assumptions) an optimal solution exists if and only if the linear system is strongly observable (i.e. observable with unknown inputs).

ISSN:0020-7179    

DOI:10.1080/00207179408921505

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

This paper considers linear control design for systems with input magnitude saturation. A general anti-windup scheme which optimizes nonlinear performance, applicable to MIMO systems, is developed. Several examples, including an ill-conditioned plant, show that the scheme provides graceful degradation of performance. The attractive features of this scheme are its simplicity and effectiveness.

ISSN:0020-7179    

DOI:10.1080/00207179408921506

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor