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Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors
Published on: January 16, 2020
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Design and Analysis of Small Size Eddy Current Displacement Sensor
Sheng-Ching Wang1, Bo-Ren Xie1, San-Ming Huang1
1Department of Mechanical Engineering, National United University, Miaoli 360302, Taiwan.
Sensors (Basel, Switzerland)
|October 14, 2022
Summary
A novel eddy current (EC) displacement sensor was designed and optimized using simulations. This EC sensor achieves high sensitivity and linearity with effective temperature drift compensation.
Area of Science:
- Electromagnetism
- Sensor Technology
- Instrumentation Engineering
Background:
- Eddy current (EC) sensors are widely used for non-contact displacement measurements.
- Miniaturization and improved accuracy, especially under varying temperatures, remain key challenges in EC sensor development.
Purpose of the Study:
- To systematically design and analyze a small-size eddy current displacement sensor.
- To develop methods for signal conversion and temperature drift compensation.
- To evaluate the sensor's performance characteristics.
Main Methods:
- Utilized electromagnetic simulations to optimize the sensor's winding structure and dimensions.
- Developed a linear-fitting approach for AC to DC signal conversion.
- Implemented a compensation strategy to mitigate temperature-induced drift.
Main Results:
- Achieved a sensor sensitivity of approximately 3 μm.
- Demonstrated a working temperature range of 25-55 °C.
- Exhibited a linearity of ±1.025%.
Conclusions:
- The proposed systematic design and compensation methods enable a high-performance small-size EC displacement sensor.
- The sensor is suitable for applications requiring accurate non-contact displacement measurement within the specified temperature range.
- This work contributes to advancing EC sensor technology for improved industrial and scientific applications.
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