Development and Prototyping of a Capacitive Oil Level Sensor for Aeronautical Applications

Abstract

Capacitive Level Sensors (CLSs) are one of the most used level-sensing technologies in the industry as they are cheap, reliable and show high sensitivity. A typical capacitive level sensor with concentric and closed cylindrical armatures has slow dynamical response when used for high viscosity liquids such as lubricating oil for aeronautic applications. This work investigates a conditioning circuit that uses a capacitance to frequency converter and that could provide fast and accurate measurements when paired with cylindrical sensor using an LC tank-based oscillator as the exciting source. The preliminary experimental results show a linear response with small error and standard deviation.