边缘电场传感器测量系统的设计与实验

边缘电场传感器是一种电容式传感器，由于具有单边穿透、信号强度可调及层析成像等优点，被广泛应用于工业过程控制中非接触测量。选择叉指型电极传感器为研究对象，分析传感器集总参数等效电路，设计测量系统的调理电路和驱动电路，基于LabVIEW平台构建测量系统，实现驱动信号产生、信号采集和预处理、扫频测量及计算等功能。对不同介电常数的样本进行检测，实验表明，该测量系统具有较好的灵敏度和低频测量精度。

Design and experimental study on measurement system for fringing electric field sensor

Fringing Electric Field （FEF） sensor which belongs to capacitive sensor is widely used in nondestructive testing, because it has the advantages of one-side access, controllability of signal strength, imaging capability, etc. The paper focused on the interdigital sensor and analyzed the lumped parameter equivalent circuit of FEF sensors. The condi- tioning and driving circuit is designed. The measurement system is built on the LabVIEW platform, with the functions of generating the driven signal, collecting the signals, sweeping frequency and calculating. The experiment for samples with different dielectric constant is done. The results show that the system has better sensitivity and measurement precision in low frequency range.