消除材料敏感性的电涡流传感器测量电路

Measurement Circuit of Eddy Current Sensor for Material Sensitivity Elimination

被测材料的电磁特性会影响传感器的输出性能,限制其使用范围。为此,在分析阻抗投影变换原理的基础上,设计了一种能实现该原理的测量电路,用以消除传感器对被测材料的敏感性。11mm传感器输出测试实验的结果表明:所用7种被测材料经线性补偿后的输出特性曲线近似重合,可用一条直线替代,实现了消除材料敏感性的功能;计算出的传感器材料敏感性误差为±1.8%。

Electromagnetic properties of the target materials can affect the sensor's output performance and restrain its range of application. Basing on analyzing the projection transformation method,a kind of measurement circuit was designed to eliminate the objective material's sensitivity. Testing the output of the 11mm sensor indicates that,after to be compensated linearly,the output characteristic curves of the seven testing materials nearly overlap and can be replaced by a straight line,it can eliminate the material sensitivity and the material's error sensitivity calculated of the sensor stays at ± 1. 8%.