Reliable control for systems with block diagonal feedback structure

The reliable control problem for decentralized systems is considered. It concerns the ability of a closed loop system to maintain stability and disturbance rejection properties during arbitrary sensor, controller, and actuator failure without being retuned. The notion of the block decentralized robust servo 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: 1) systems satisfying certain steady state interaction characteristics and 2) systems possessing minimum phase “block” transmission zeros. Accordingly, two types are 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