基于差动式电容传感器的弹簧检长系统  

Spring length detection system based on differential capacitance sensor

作　　者：张永超[1] 赵录怀[2] 杨钧翔 ZHANG Yongchao;ZHAO Luhuai;YANG Junxiang(Xi an Jiaotong University City College,Xi an 710018,China;School of Electrical Engineering,Xi an Jiaotong University,Xi an 710048,China)

机构地区：[1]西安交通大学城市学院,西安710018 [2]西安交通大学电气学院,西安710048

出　　处：《工业仪表与自动化装置》2020年第4期74-76,共3页Industrial Instrumentation & Automation

摘　　要：针对弹簧检长系统测量误差大的问题,该文设计了基于差动式电容传感器的弹簧检长系统,该系统由差动式变面积式电容传感器、双T形交流电桥测量电路、信号调理电路、FPGA和显示组成,经试验得到电压与弹簧相对长度函数关系,在实际使用中运用该函数关系通过测量电压计算出待测弹簧长度。经实验测得电压与弹簧相对长度拟合函数其线性度为1%,灵敏度为2.5292 mV/mm,分辨力为0.05 mm,按照国家标准1级弹簧长度误差小于标准弹簧±0.2 mm为合格。实验表明,该系统完全可以满足弹簧检长要求,且线性度好、灵敏度高、分辨力强、稳定性好;经实际和标准仪器相比准确率达到100%,且比现有设备操作简单、成本低。Aiming at the problem of large measurement error of spring length detection system,this paper designs a spring length detection system based on differential capacitance sensor.The system consists of differential variable area capacitance sensor,double T-shaped AC bridge measurement circuit and signal conditioning circuit,FPGA and display composition,the voltage and the relative length function of the spring are obtained through experiments.In the actual use,the function relationship is used to calculate the length of the spring to be tested by measuring the voltage.The linearity of the voltage and spring relative length fitting function is 1%,the sensitivity is 2.5292 mV/mm,and the resolution is 0.05 mm.According to the national standard,the spring length error is less than the standard spring±0.2 mm.The system can fully meet the requirements of spring inspection,and has good linearity,high sensitivity,strong resolution and good stability.Compared with the standard instrument,the accuracy rate is 100%,and the operation is simpler and the cost is lower than the existing equipment.

关 键 词：弹簧检长 差动式电容传感器 双T形交流电桥 

分 类 号：TM932[电气工程—电力电子与电力传动]