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Updated: Apr 18, 2026

Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors
Published on: January 16, 2020
Note: Eddy current displacement sensors independent of target conductivity
Hongbo Wang1, Wei Li1, Zhihua Feng1
1Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui 230026, China.
Abstract:
Eddy current sensors (ECSs) are widely used for non-contact displacement measurement. In this note, the quantitative error of an ECS caused by target conductivity was analyzed using a complex image method. The response curves (L-x) of the ECS with different targets were similar and could be overlapped by shifting the curves on x direction with √2δ/2. Both finite element analysis and experiments match well with the theoretical analysis, which indicates that the measured error of high precision ECSs caused by target conductivity can be completely eliminated, and the ECSs can measure different materials precisely without calibration.
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