摘要:

For linear controllers, the anti-windup compensator based on conditioning technique is often treated as a special case of the generalised anti-windup compensator. The conditioning technique is then defined simply by a special observer in the generalised anti-windup compensator. Instead, in this paper the concept of back calculation or the modified setpoint is emphasised, which is indeed the conceptual basis for the derivation of the conditioning technique. The behaviour of the modified setpoint is investigated by use of a simple example, and an inherent weakness (‘short-sightedness’) in the conditioning technique is demonstrated. A simple modification to the conditioning technique that reduces the effect of short-sightedness is presented, and its anti-windup compensation properties are investigated. Also, a general approach to the conditioning technique is proposed by introducing a filtered setpoint. This approach provides a parameterisation to deal not only with the short-sightedness problem but also with the other drawbacks of the conditioning technique. An important outcome of this generalisation is that it unifies and interprets through the conditioning technique a class of AWCs described in the literature.

DOI:10.1049/ip-d.1992.0016

出版商:IEE    

年代:1992

数据来源: IET

摘要:

A new approach is developed for fault detection in linear, stochastic, interconnected dynamic systems, based on designing a set of decentralised Kalman filters for the subsystems resulting from overlapping decomposition of the overall large-scale system. The malfunctioning sensors can be detected and isolated by comparing the estimated values of a single state from different Kalman filters. The new method is applied to a sixth-order system represented by a ladder network.

DOI:10.1049/ip-d.1992.0017

出版商:IEE    

年代:1992

数据来源: IET

摘要:

A method is presented for the systematic design of stabilising decentralised controllers for large-scale interconnected dynamical systems. The design method is based on (i) decentralised implementation of global controllers obtained by using existing global controller design methods, (ii) model reduction of dynamical systems, and (iii) modelling of the interactions among the subsystems comprising the global closed-loop control system. This is used for generating local corrective control signals, which would account for these interactions. The resulting decentralised controller uses local information only to generate local control inputs. It comprises local state feedback controllers and feedforward compensators. Three distinct schemes for the implementation of the controller are proposed. They all guarantee near optimal performance. A four-station interconnected dynamical system is considered. Results of time simulation studies demonstrate that the overall performance of the system under the proposed decentralised controller is near that of the global optimal controller.

DOI:10.1049/ip-d.1992.0018

出版商:IEE    

年代:1992

数据来源: IET

摘要:

A unified approach is developed for identification of linear time-invariant systems. It is shown that, given the experimental frequency-response data of the system, the plant can be identified using a simple, numerically reliable algorithm. Further, an error bound is derived for exponentially stable systems when the frequency-response data are corrupted by bounded noise. An example is presented to illustrate the proposed algorithm.

DOI:10.1049/ip-d.1992.0019

出版商:IEE    

年代:1992

数据来源: IET

摘要:

In this paper, the problem of forming desired transients for systems which are governed by partial differential equations is discussed. It is assumed that information about external disturbances is incomplete and that there are finite dimensional controls. The design method called the localisation method is used. Such problems as choices of structure of the control law, realisability conditions, control accuracy, influence of the differentiating filters and noises, are considered. Simulation results are also presented.

DOI:10.1049/ip-d.1992.0020

出版商:IEE    

年代:1992

数据来源: IET

摘要:

A polynomial solution to the LQG optimal-control problem is presented for a system with special controller structure and robust cost-weighting terms. The controller structure has the advantages of both single- and two-degrees-of-freedom designs. The effect of introducing a common robustness weighting term in the cost index is considered. It is shown that this leads to an additional gain term in the Youla parameterised form of the controller. To illustrate the advantages of the controller structure and the influence of the robustness weighting term, a flight control system design example is presented.

DOI:10.1049/ip-d.1992.0021

出版商:IEE    

年代:1992

数据来源: IET

摘要:

An integral variable structure control (IVSC) approach for robot manipulators is presented to achieve accurate servo-tracking in the presence of load variations, parameter variations and nonlinear dynamic interactions. A procedure is proposed for choosing the control function so that it guarantees the existence of the sliding mode and for determining the coefficients of the switching plane and the integral control gain such that the IVSC approach has the desired properties. Furthermore, a modified proper continuous function is introduced to overcome the chattering problem. The proposed IVSC approach has been simulated for the first three links of a PUMA 560 robot arm as an illustration. The simulation results demonstrate the potential of the proposed scheme.

DOI:10.1049/ip-d.1992.0022

出版商:IEE    

年代:1992

数据来源: IET

摘要:

The paper presents an adaptive implementation of internal model principle for continuous time systems. It is shown that without persistent excitation the adaptive control system with the internal model principle is globally stable in that the plant input and output remain bounded. It is also shown that the stability of the adaptive control system is still maintained in the presence of plant unmodelled dynamics and other bounded disturbances.

DOI:10.1049/ip-d.1992.0023

出版商:IEE    

年代:1992

数据来源: IET

摘要:

The objective of the paper is the search for algorithms to reduce the spatial-time complexity of dynamic programming. These algorithms have been verified in second-order continuous systems, with indexes of performance where the time explicitly appears. The use of such algorithms is vital when dealing with third-order systems and second-order stochastic systems.

DOI:10.1049/ip-d.1992.0024

出版商:IEE    

年代:1992

数据来源: IET

摘要:

An adaptive inferential algorithm is developed for estimation and control of multirate systems. The outputyis measuredJtimes slower than the secondary process outputvand the inputu, but an output estimateYeis produced at each sampling interval ofvandu. Compared with previous work on multirate inferential systems, the proposed algorithm has a more formal theoretical basis. For example, the outputyis related to the secondary outputvnot only through external stochastic disturbances but also through the internal system structure. Convergence properties are formally proven for the case of zero external stochastic disturbances, and a simplified algorithm is proposed for practical applications. Simulated results illustrate the convergence properties of the algorithm and the improvement obtained in simple feedback control systems.

DOI:10.1049/ip-d.1992.0025

出版商:IEE    

年代:1992

数据来源: IET