Fault-tolerant Control Systems

The seriesAdvancesinIndustrialControl aims to report and encourage te- nologytransfer in controlengineering. The rapid development of controlte- nology has an impact on all areas of the control discipline. New theory, new controllers, actuators, sensors, new industrial processes, computer methods, new applications, new philosophies. . . , new challenges. Much of this devel- ment work resides in industrial reports, feasibility study papers, and the - ports of advanced collaborative projects. The series o?ers an opportunity for researchers to present an extended exposition of such new work in all aspects of industrial control for wider and rapid dissemination. Control system design and technology continues to develop in many d- ferent directions. One theme that the Advances in Industrial Control series is following is the application of nonlinear control design methods, and the series has some interesting new commissions in progress. However, another theme of interest is how to endow the industrial controller with the ability to overcome faults and process degradation. Fault detection and isolation is a broad ?eld with a research literature spanning several decades. This topic deals with three questions: • How is the presence of a fault detected? • What is the cause of the fault? • Where is it located? However, there has been less focus on the question of how to use the control system to accommodate and overcome the performance deterioration caused by the identi?ed sensor or actuator fault.

Fault-tolerant Control Systems reports the development of fault diagnosis and fault-tolerant control (FTC) methods with their application to real plants. After an introduction to fault diagnosis and FTC, a chapter on actuators and sensors in systems with varying degrees of nonlinearity leads to three chapters in which the design of FTC systems is given thorough coverage for real applications:

• a winding machine typifying a subsystem in various sheet and film processes;

• a hydraulic three-tank system representative of those used widely in chemical plants; and

• an active suspension system demonstrating application in whole large-scale systems by splitting into subsystems.

Actuator and sensor faults are accommodated within the control-law design and the integration of fault diagnosis models in the FTC systems described. Commentary is given on the recent results presented. Critical failures – the loss of system observability from total loss of a sensor and of controllability from complete loss of an actuator – are considered. Linearized systems around an operating point and nonlinear systems are discussed and illustrated. A complete simulation platform of the three-tank system, in closed-loop, with or without actuator and sensor faults, is provided for the use of the reader via download from www.springer.com/978-1-84882-652-6.

With its emphasis on real application, Fault-tolerant Control Systems makes an important contribution to the literature on FTC and will be of significant assistance to practicing control engineers with problems of this nature to solve. The book will also be of use to academic researchers and graduate students interested in FTC, bringing to their attention the need to adapt their methods for implementation and suggesting ways in which this can be done.