Fault diagnosis and fault tolerant control design for a class of hybrid systems

In this paper, the fault diagnosis (FD) and fault tolerant control (FTC) problem for a class of hybrid systems modeled by hybrid automata is intensively discussed. An observer-based FTC method is proposed for the hybrid system with uncontrollable state dependent switching and without full continuous state measurements. Two kinds of faults are considered: Continuous faults that affect each mode; Discrete faults that affect the mode transition. A novel observer is designed for each mode which is not affected by continuous faults and sensitive to mode transitions. Sufficient conditions are given under which the hybrid system can be stabilized in the sense of LaSalle invariance principle. An example of CPU processing control is provided to show the efficiency of the proposed method.