Observer Design and Residual Evaluation of System Actuators With Lipschitz Nonlinearity

Summary: This paper studies observer design and residual evaluation of system actuators with Lipschitz nonlinearity. A fault detection observer for actuators that satisfies the Lipschitz nonlinearity condition is proposed in the finite‐frequency domain to ensure its robustness to disturbances and sensitivity to faults under bounded fault amplitude conditions. On this basis, in order to improve the accuracy of fault detection, a redesign method of dynamic threshold for fault detection is proposed. The effectiveness of the proposed methods is illustrated by numerical simulations.