Sliding Mode Interval Observer Fault Detection and Adaptive Sliding Mode Fault‐Tolerant Control Designs for Uncertain Nonlinear Singular Systems

ABSTRACT In this article, the method of fault detection using a sliding mode interval observer (SMIO) is studied for uncertain nonlinear singular systems with an actuator fault. Assuming that the actuator fault does not exist, the SMIO of uncertain nonlinear singular systems is designed by two transformations. The output of SMIO is used to construct the upper and lower bounds of the output when the system does not contain an actuator fault, and the fault detection is realized by judging whether the system output exceeds the constructed upper and lower bounds. Based on the system after rank transformation, an adaptive sliding mode fault‐tolerant control (ASMFTC) scheme is designed to compensate for the influence of the fault on the uncertain nonlinear system, and a fault estimation strategy is proposed. Finally, the correctness and effectiveness of the proposed method are illustrated by two examples.