线性位移检测信号调理电路设计  

Design of signal conditioning circuit for linear displacement detection

作　　者：洪琴 周亮 贾中宁 HONG Qin;ZHOU Liang;JIA Zhongning(Software Engineering Institute of Guangzhou,Guangdong Guangzhou 510990,China)

机构地区：[1]广州软件学院计算机系,广东广州510990

出　　处：《工业仪表与自动化装置》2024年第3期117-122,共6页Industrial Instrumentation & Automation

基　　金：广州软件学院2023年“质量工程”建设项目(JYS202302)。

摘　　要：线性位移检测时会输出一个调幅波,幅值反映了位移大小,但位移方向无法判断。针对此问题,提出一种信号调理电路,主要由相敏检波器和低通滤波器组成。首先对其电路的工作原理做了理论分析、仿真设计与验证,然后设计制作PCB电路、对各个电路测试点的波形进行测试与验证。最后将其应用于LVDT线性位移测量,测得灵敏度S=-1.97672 V/mm,非线性误差γ=0.83%,实验结果表明,该相敏检波器具有结构简单、调试方便、抑制噪声能力强、可靠性高等优点,能够实现对信号的准确检测和解调。When performing linear displacement detection using LVDT,an amplitude-modulated wave is output,with the amplitude reflecting the displacement size,but the direction of displacement cannot be determined.To address this issue,a signal conditioning circuit is proposed,mainly composed of a phase-sensitive detector and a low-pass filter.First,theoretical analysis,simulation design,and verification of the working principle of the circuit were conducted.Then,PCB circuits were designed and fabricated,and the waveforms at various test points of the circuits were tested and verified.Finally,it was applied to LVDT linear displacement measurement,with a measured sensitivity of S=-1.97672 V/mm and a nonlinear error ofγ=0.83%.Experimental results show that the phase-sensitive detector has the advantages of simple structure,convenient debugging,strong noise suppression capabilities,and high reliability,enabling accurate detection and demodulation of signals.

关 键 词：LVDT 相敏检波 信号调理 低通滤波 

分 类 号：TN702[电子电信—电路与系统] TP212.13[自动化与计算机技术—检测技术与自动化装置]