涡流测距探头灵敏度与磁性芯片位置的相关性研究

Research on the Correlation between the Sensitivity of Eddy Current Distance Measuring Probe and the Position of Magnetic Chip

本文基于涡流测距理论,推导了激励线圈置于一定厚度金属平板上,空间内不同位置处复合磁场强度与位移S的关系式.利用Maxwell软件对三维模型进行求解,分析距离线圈下边沿d处,直线L1上各点磁感应强度峰值随S变化规律,并引入△B/△S作为L1上各点对S变化敏感程度的评价指标.结果 表明,L1上各点与线圈轴心和被测板距离越小,△B与△S比值越大,表明磁性芯片放置该位置对S值检测灵敏度更高,认为对管道变形检测更有利.

In this paper,based on the theory of eddy current ranging,the relationship between the compound magnetic field intensity and displacement S at different positions in the space of the excitation coil on a certain thickness of metal plate is deduced.The 3 d model is solved by using Maxwell's software,to distance under the coil edge d analysis on each point on the straight line LI with magnetic induction intensity peak S change rule,and introduce A B/A S as each point on the LI is sensitive to change S degree of evaluation index.Results show that the smaller the distance between each point on LI and the axis of the coil and the board under test,the greater the ratio of AB to AS,indicating that the position of the magnetic chip placed at this position is more sensitive to the detection of S value,and it is considered to be more beneficial to the detection of pipeline deformation.