Suppression Efficiency of the Correlated Noise and Drift of Self-oscillating Pseudo-differential Eddy Current Displacement Sensor

Journal article (2016)

Authors

Chaturvedi Electronic Instrumentation - EEMCS
Vogel Electronic Instrumentation - EEMCS
Nihtianov Electronic Instrumentation - EEMCS
Research Group
Electronic Instrumentation (EEMCS) (TU Delft)
Copyright: © 2016 V. Chaturvedi, J.G. Vogel, S. Nihtianova
DOI: https://doi.org/10.1016/j.proeng.2016.11.312
Sensor Drift Oscillator Nonlinearity Displacement Demodulator Eddy-current Finite elelement
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Published Date

01-09-2016

Language

English

Faculty

Electrical Engineering, Mathematics and Computer Science

Department

Microelectronics

Research Group

Electronic Instrumentation

Abstract

The suppression efficiency of the correlated noise and drift of self-oscillating front-end circuit in a pseudo-differential eddy-current displacement sensor (ECDS) is investigated using COMSOL and MATLAB. The transfer characteristic of the sensor coil, excited at 200 MHz, is obtained through a FE model in COMSOL. The characteristic is linearized to a second-order fit around a standoff distance to the target (xso) of 55 μm. The nonlinearity of the interface is modelled in MATLAB. It is found that, in order to tolerate 1% drift in the oscillator amplitude, a maximum 2nd harmonic distortion (HD2) of the interface has to be less than −72 dB when the sensor HD2 is −51.5 dB for 5 μm displacement range around xso = 55 μm.