In this paper, the reliable control problem for decentralized systems is considered. It concerns the ability of closed-loop system to maintain stability and disturbance rejection properties during arbitrary sensor, controller, and actuator failure without being retuned. The notion of block decentralized robust servomechanism problem with complete reliability is first introduced to address systems with a block diagonal feedback structure. This is followed by establishing two conditions for reliability: (i) systems satisfying certain steady-state interaction characteristics or (ii) systems possessing minimum phase “block” transmission zeros. Accordingly, two types of decentralized controllers are applied to achieve reliable control for these two categories of systems. Simulation examples are also included to illustrate the properties of the reliable control system.

Issue Section:
Technical Briefs
Keywords:
reliability, decentralised control, large-scale systems, closed loop systems, feedback, servomechanisms, reliable control, fault tolerant systems, decentralized control, servomechanism problem, component failure
Topics:
Closed loop systems, Control equipment, Failure, Feedback, Reliability, Servomechanisms, Steady state, Theorems (Mathematics), Sensors, Actuators, Stability
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Copyright © 2006
 by American Society of Mechanical Engineers
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