Minute Displacement Measurement with Eddy Current Sensor

Abstract:

Typically, eddy current sensor describes the distance by measuring the voltage reflected impedance of the coil. But in some cases, such as the measurement of different materials, the voltage (impedance Z) doesn’t change monotonously which may affect the sensor Measuring range and even the accuracy of the results. So we designed a new structure of eddy current sensor using phase sensitive detection techniques to analysis the impedance of the coil. After the A/D convention of C8051F020 MCU, the signal is analyzed and processed in PC,the displacement of the object is got. The experiment shows that the device has a high accuracy and stability, suitable for the tiny-distance measurement of different materials.

• Periodical: Advanced Materials Research (Volume 426)
• Pages: 251-254
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.426.251
• Online since: January 2012
• Authors: Q.S. Xu, C.S. Ai
• Keywords: Distance Measurement, Eddy Current Sensor, Impedance Analyze, Phase Sensitive Detection

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