Application of Thau Observer for Fault Detection of Micro Parallel Plate CapacitorSubjected to Nonlinear Electrostatic Force

This paper investigates the fault detection of a micro parallel plate capacitor subjected tononlinearelectrostatic force. For this purpose, Thau observer, which has demonstrated good performance in faultdetection of nonlinear systems,as well asgoverning nonlinear dynamic equation of the capacitor,ispresented. Upper and lower threshold for fault detection have been obtained. The robustness of theobserver to noise, uncertainty as well as sensitivity to faults wasinvestigated. Finally, simulation resultsfor fault detection of the capacitor are obtained and the ability of the observer in the vicinity ofdynamic pull-in voltage has been checked