Control reconfigurability of linear time-invariant systems

For any fault-tolerant control method to take effect, sufficient redundancy must exist in the plant (process) to be controlled. This paper is intended to establish a means of measuring the level of redundancy in connection wi th feedback control by borrowing the notion of the second-order modes. In p articular, it is assumed that foreseeable faults of a process are parameter ized in the model of the process. The smallest second-order mode is used as a measure of the potentiality of the process to maintain a certain perform ance through control reconfiguration at the occurrence of the worst faults over a prescribed set in the fault parameter space. This measure is called by the authors a control reconfigurability. The control reconfigurability i s calculated for two process models to show its relevance to redundant actu ating capabilities in the models. (C) 2000 Elsevier Science Ltd. All rights reserved.