Title
Probe Design For High-Precision Eddy-Current Displacement Sensors
Abstract
State-of-the-art industrial Eddy-Current Displacement Sensors (ECDSs) are typically not suitable for use in high-precision applications due to their low resolution and poor stability. By using a smaller, flat sensing coil, a reference coil, a dedicated readout chip and by operating at much higher excitation frequency a higher measurement sensitivity and better mechanical and thermal stability can be achieved. To use the sensor in industrial applications, the chip and the coils must be integrated in a small package. This paper presents a probe design for a high-precision ECDS, aiming at compactness and low thermal sensitivity. In this design, the sensing coil and the reference coil are closely spaced to minimise thermal gradients. The coils can, together with intermediate shielding and capacitive tilt electrodes, be integrated into a single stack only 2 mm thick and 12 mm in diameter, which can be realised on a multilayer PCB. Thermomechanical modelling shows that placing the readout chip on a separate PCB leads to significantly decreased self-heating compared to placement directly on the stack. Experiments show that the inductance behaviour of the realised stack is similar to that of the model.
Year
DOI
Venue
2018
10.1109/IECON.2018.8591562
IECON 2018 - 44TH ANNUAL CONFERENCE OF THE IEEE INDUSTRIAL ELECTRONICS SOCIETY
Keywords
Field
DocType
eddy-current sensor, displacement measurement, probe design, coil inductance, self-heating
Thermal,Inductance,Control theory,Electromagnetic shielding,Excitation,Capacitive sensing,Chip,Electromagnetic coil,Eddy current,Acoustics,Engineering
Conference
ISSN
Citations 
PageRank 
1553-572X
0
0.34
References 
Authors
0
3
Name
Order
Citations
PageRank
Johan Vogel112.17
Vikram Chaturvedi2243.41
Stoyan Nihtianov38018.83