A modified linear capacitive displacement transducer for any range

Area of Science:

• Electrical Engineering
• Instrumentation and Measurement

Background:

• Capacitive displacement transducers are widely used for non-contact measurement.
• Traditional designs often suffer from non-linearity and various error sources.
• Minimizing these errors is crucial for high-precision applications.

Purpose of the Study:

• To develop a modified linear capacitive displacement transducer.
• To minimize measurement and non-linearity errors.
• To achieve a linear output related to displacement for any range.

Main Methods:

• A modified transducer design featuring sensing and reference capacitors.
• Each capacitor utilizes a noninductive double layer short-circuited winding on a hollow cylinder.
• A displaceable conducting disk within the sensing cylinder and a fixed disk in the reference cylinder.
• Measurement of the difference in combined cylindrical-perpendicular plate capacitances.

Main Results:

• The developed transducer exhibits a linear relationship between output and displacement over the entire sensing range.
• Errors due to atmospheric parameters, parasitic fringe capacitance, stray capacitance, and plate shifting are significantly minimized.
• The cancellation of non-linearity factors in the differential measurement ensures high accuracy.
• Experimental results validate the derived characteristic equations with excellent accuracy and repeatability.

Conclusions:

• The modified linear capacitive displacement transducer effectively overcomes limitations of conventional designs.
• The transducer provides highly accurate and linear displacement measurements.
• This technology offers a robust solution for precise displacement sensing in various industrial and scientific fields.