基于数字锁相放大器的电涡流位移传感器  

Eddy Current Displacement Sensor Based on Digital Lock-in Amplifier

作　　者：李昌 周松斌 LI Chang;ZHOU Songbin(Institute of Intelligent Manufacturing,Guangdong Institute of Intelligent Manufacturing,Guangzhou Guangdong 510075,China)

机构地区：[1]广东省科学院智能制造研究所,广东广州510075

出　　处：《电子器件》2022年第2期445-449,共5页Chinese Journal of Electron Devices

基　　金：国家自然科学基金青年基金(6180022835);广东省自然科学基金(2020A1515010768);广州市产业技术重大攻关计划(201902010040);广东省重点领域研发计划(2019B010154002)

摘　　要：针对电涡流位移传感器电路结构复杂、线性度低等问题,采用数字锁相放大技术来测量传感器线圈损耗,再通过线圈损耗测量位移大小。充分利用了STM32F3系列单片机的片内资源:片内数模转换器与DMA控制器配合产生激励信号,模数转换器与DMA控制器配合采集信号,浮点运算器运行数字锁相放大器算法,最后用片内数模转换器输出线性校准后的数值,实现了一种新型的电涡流位移传感器。传感器的电路简洁,线性度优于0.51%,动态响应时间小于2 ms。In order to solve the problem of low linearity and complex circuit structure of eddy current displacement sensor,the digital phase-locked amplification technology is adopted to measure the sensor coil loss,and then the displacement through the coil loss is measured,which makes full use of the STM32 F3 series MCU chip resources.In-chip digital-to-analog converter with DMA controller cooperates to generate excitation signal,analog-to-digital converter with DMA controller cooperates to collect signal,and the floating-point arithmetic runs the digital phase-locked amplifier algorithm.Finally,a new type of eddy current displacement sensor is realized by using the on-chip digital-to-analog converter to output the values after linear calibration.The circuit of the sensor is simple,the linearity is better than 0.51%,and the dynamic response time is less than 2 ms.

关 键 词：数字锁相放大器 电涡流位移传感器 相位测量 幅度测量 阻抗测量 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TN722[自动化与计算机技术—控制科学与工程]