摘要 :电涡流传感器是基于电涡流效应的传感器。本文通过对传统电涡流传感器测量电路的熟悉,分析并设计了新的电涡流传感器线圈阻抗测量电路,将变化的阻抗量转换成相应的电量,由此得到变化阻抗的信息。为了提高电路的集成度、稳定性和可靠性,此电路应用了AD5933芯片,结合基准电压工作。AD5933处理的正弦波信号都是单极性的直流信号,而线圈所需的是双极性的正弦波交流信号,所以在AD5933与线圈之间,加入了信号调理电路用于两者之间的匹配。本电路主要由AD5933、基准电压电路、信号调理电路组成,再通过单片机得到阻抗的信息。
关键词:电涡流; AD5933; 调理电路; 阻抗测量
Abstract :The eddy current sensor is based on the eddy current effect. In this paper, familiarity with traditional eddy current sensor measuring circuit, I analysis and design the new eddy current sensor coil impedance measurement circuit. Impedance changes is converted into the corresponding power, and then we get information of the impedance changes. In order to improve the level of integration, stability and reliability of the circuit, this circuit has applied the AD5933 chip, and combined with the reference voltage. Sine wave signal processing by AD5933 is unipolar DC signal. But the signal needed of coil is a bipolar sine wave AC signal. so I add a signal conditioning circuit to match the AD5933 and the coil. This circuit is composed mainly by the AD5933, the reference voltage circuit and the signal conditioning circuit, and we can get information of impedance through the MCU.
Key words: Eddy current; AD5933; signal conditioning circuit; impedance measurement