D-stable condition formulation for cascade reconfiguration control design

Abstract

The paper is concerned with the problem of reconfiguration to retain fault tolerance in control of linear continuous-time systems with system parameter faults. Following the concept of fault tolerant control systems the main idea is to use a model output as the reference to be followed when a fault occurs, while the nominal control loop is kept untouched and the nominal controller remains a part of the reconfigured control loop. The full state control tenet is proposed for nominal control strategy and the static output control principle for the compensation control law specification. Exploiting u-stability circle regions, new conditions for control laws parameter design are introduced and proven and a cascade-like reconfiguration structure stability is analyzed in the paper. The results, offering the sufficient and necessary design conditions, are illustrated with a numerical example to note the effectiveness of the proposed approach.