摘要
鉴于市场应用的油中水含量检测方法和仪器的不足,设计了一种基于边缘电场效应和PCB技术的水含量测量仪。仪器由检测探头、探头电容检测电路、嵌入式处理器、外置SRAM、SD卡存储器、RS485通信模块、触摸屏、键盘、电源模块等组成。检测探头利用电容极板的边缘电场效应,并通过PCB技术制造;探头电容检测采用精度高达28位的电容检测芯片和侧贴SMA屏蔽头以提高抗干扰性能;主控采用嵌入式处理器STM32F407ZGT6,运行μCOSIII多任务操作系统;外置SRAM和SD卡提供运行和存储空间;触摸屏和键盘为用户提供交互体验。实验测试:大豆油中水含量在0%~80%范围内,检测误差小于3%,灵敏度为3.3 pF/%。
In view of the market application deficiency of the water content detection method and the instrument,a measurement system based on capacitive fringing field effect and PCB technology was designed,consisting of self-designed detection probe,capacitance detection circuit,embedded processor,external SRAM,SD card memory,RS485 communication module,LCD touch screen,keyboard,power supply module and other components.The design of oil-water capacitance detection probe was made by the fringing field effect of the capacitor plate PCB technology.Capacitance detection circuit was designed in using the up to28-bit accuracy capacitance detection chip and the side stick SMA shielding head,which could improve the anti-jamming performance of the circuit. The system control hardware utilized embedded processor STM32 F407 ZGT6 and ran u COSIII real-time embedded multi-tasking operating system.External SRAM and SD card memory provided the system operation and storage space.LCD touch screen and keyboard for users provided good interaction experience.Experimental data showed that the oil-water measurement system was a successful implementation of the prototype,which detection error was less than 3% and sensitivity could be achieved in 3.3 pF/%,given the oil-water ranged from 0 to 80%.
出处
《仪表技术与传感器》
CSCD
北大核心
2018年第1期25-30,共6页
Instrument Technique and Sensor
基金
江苏省普通高校专业学位研究生实践创新计划项目(SJZZ16_0154)
制造过程测试技术-省部共建教育部重点实验室开放基金项目(14zxzk02)
江苏省信息与通信工程优势学科资助项目
关键词
电容检测探头
边缘电场效应
PCB技术
嵌入式操作系统
capacitive detecting probe
capacitive fringing filed effect
PCB technology
embedded operating system
