基于ANSYS电涡流测厚线圈的优化设计

Optimal Design of Eddy Current Thickness Coil Based on ANSYS

以连铸结晶器内的45#钢薄板坯为研究对象,采用有限元软件ANSYS建立电涡流测多层板厚度模型。研究了涡流测厚线圈在不同外半径、厚度和匝数的情况下,线圈的阻抗变化和金属板电涡流密度变化趋势,通过对变化趋势进行分析得出线圈最优尺寸。研究结果表明:在线圈激励频率和提离不变的条件下,线圈外径大时,涡流线圈的敏感范围大,线性范围相应就会增大,但灵敏度降低,反之亦然;外径大小一定时,线圈越薄,线圈的线性测量范围和灵敏度越高;匝数的增多,使线性范围增大、灵敏度降低,同时抑制温漂的产生。

With 45# steel in the thin slab continuous casting mold as the research object, the finite element software ANSYS was used to establish the eddy current measurement model of the thickness of the muhilayer board. In the case of eddy current thickness measurement coil with different outer radiuS, different thickness and different turns, the impedance of the coil and met- al plate eddy current density changes trend was analyzed.The optimal coil size was analyzed through the trend analysis.The results showed that under the condition of the same excitation frequency and the lift off , when the coil diameter is large, the sensitive range of the eddy current coil is large, the linear range can increase, but the sensitivity reduces ,vice versa.When the outer di- ameter is determined, the thinner the coil is, the higher the linear measurement range and the sensitivity of the coil is.The increasing of the number of turns makes linear range increased and sensitivity decreased, at the same time generation of tempera- ture drift is inhibited.