电容式灌装液位检测系统的设计  

Design of Capacitive Filling Level Detection System

作　　者：徐乐年 林敏 孙崇雨 许艳云 XU Le-nian;LIN Min;SUN Chong-yu;XU Yan-yun(College of Electronic Communication and Physics,Shandong University of Science and Technology,Qingdao 266590,China)

机构地区：[1]山东科技大学电子通信与物理学院,山东青岛266590

出　　处：《仪表技术与传感器》2019年第2期72-74,共3页Instrument Technique and Sensor

摘　　要：基于CDC的电容式灌装液位检测系统可适用于工业生产中的液体灌装高度的检测。该系统设计了能够对灌装液位进行非接触有效测量的电容式传感器结构,并使用电容数字转换器AD7745进行电容测量。硬件上采用接地、外加屏蔽罩等措施降低电磁干扰,软件上对AD7745寄存器进行合理设置实现高精度测量。实验结果表明:在恒温的条件下该设备反应灵敏且稳定性高,成本低、可实时在线监测及远程操作;检测速度最高可达72 000瓶/h,检测精度±2 mm,误剔除率小于1%。This paper introduced a CDC-based capacitive filling level detection system that can be applied to the detection of liquid filling height in industrial production.The system was designed with a capacitive sensor structure that enables non-contact measurement of the filling level and used the AD7745 capacitance-to-digital converter for capacitance measurement.The hardware adopted grounding,plus shielding cover and other measures to reduce electromagnetic interference,and the software reasonably set the AD7745 register to achieve high-precision measurement.The experimental results show that the device is sensitive,stable,cost-effective and real-time on-line monitoring and remote operation under constant temperature.The detection speed is up to 72 000 bottles / h,the detection accuracy is ±2 mm and the false rejection rate is less than 1%.

关 键 词：液位检测 AD7745 电容耦合 电磁兼容 

分 类 号：TP277[自动化与计算机技术—检测技术与自动化装置]