Fault detection for sandwich systems with hysteresis based on robust observer

Abstract

In the real application, realizing the accurate fault prediction of non-smooth sandwich system with hysteresis which widely exists in the real engineering systems is of great importance. Therefore, a novel dynamic robust observer is proposed in this paper. First, the non-smooth sandwich system with hysteresis is transformed into a system in which conventional dynamic robust observer design method can be applied by converting the non-smooth item into a general disturbance. Then, by zeros assignment and minimizing the H_{∞, F} /H_-,F indicator on the basic operation zone, the feedback matrices of this observer can be obtained. After that, the simulation results are presented. The comparison between the proposed robust non-smooth scheme and the conventional method demonstrated that the proposed robust fault detection approach can detect the actuator and sensor faults accurately and quickly which the conventional observer can not detect the faults at all. Moreover, the missing and false alarms are effectively reduced by the robust observer.