Abstract    This paper investigates the fault detection of a micro parallel plate capacitor subjected to nonlinear electrostatic force. For this end Thau observer, which has good ability in fault detection of nonlinear system has been presented and governing nonlinear dynamic equation of the capacitor has been presented. Upper and lower threshold for fault detection have been obtained. The robustness of the observer to noise and uncertainty and sensitivity to fault has been investigated. Finally, simulation results for fault detection of the capacitor are presented and the ability of the observer in the vicinity of dynamic pull-in voltage has been checked.

Keywords    Fault detection, Thau observer, nonlinear force, micro-parallel plate capacitor, noise and uncertainty

چکیده    در این مقاله عیب­یابی میکروخازن صفحه موازی که تحت تاثیر نیروی غیر­خطی الکترواستاتیک قرار دارد؛ مورد بررسی قرار گرفته است. به این منظور روئیتگر تائوکه قابلیت خوبی جهت عیب­یابی سیستمهای غیر خطی دارد؛ ارائه شده است و معادلات غیرخطی دینامیکی خازن تعیین و ارائه گشته است. آستانه ­ی بالایی و پایینی عیب­یابی تعیین شده و حساسیت روئیتگر به عیب و مقاومت آن در مقابل وجود اغتشاش و عدم قطعیت سنجیده شده است. در انتها نتایج شبیه سازی برای عیب­یابی خازن تعیین و ارائه گشته و توانایی روئیتگر در عیب­یابی سیستم در نزدیکی ولتاژ ناپایداری سنجیده شده است

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