QuickField
A new approach to field modelling

Industrial

Educational

Scientific

Sample problems

Examples gallery

Step-by-step tutorials

Verification examples

Programming examples

Distributive examples

Success stories

Customers

Main >> Applications >> Sample problems >> Capacitive displacement sensor

Capacitive displacement sensor

QuickField simulation example

Capacitive displacement sensor working principle is based on the capacitance change with variation of the mutual position of the two coaxial cylindrical electrodes.

Problem Type
Axisymmetric problem electrostatics.

Geometry
Capacitive displacement sensor Capacitive displacement sensor working principle is based on the capacitance change with variation of the mutual position of the two coaxial cylindrical electrodes 30 mm ΔU 20 mm R5 mm

Given
Relative permittivity of air ε = 1.

Task
Calculate the capacitance as a function of the inner cylinder's displacement.

Solution
We apply the potential difference of ΔU = 1 V to the cylinders and measure the electric field energy W stored in the air.
The capacitance is 2*W / ΔU ².
A set of QuickField problems with different cylinders position is automatically generated by the Label Mover tool.

Results
At zero displacement the capacitance is 2*7.57e-12 / 1² = 15.14 pF.


Capacitive displacement sensor