粮仓料位智能检测系统研究.doc

粮仓料位智能检测系统研究

摘要：粮食储藏是国家为防备战争、灾荒及其它突发性事件而采取的有效措施，因此，粮食的安全储藏具有重要意义。针对粮食储藏装置料位检测的需要,设计了一种以双电容料位传感器的智能检测系统，双电容传感器技术,消除了温、湿度等干扰因素,使该检测系统能适应恶劣的工业环境。同时该系统以AT89C51单片机为微控制器，由双电容式料位传感器、传感器信号检测电路,CPU及显示电路、报警电路和系统软件等构成。

关键词：双电容式传感器；单片机；微小电容测量电路； C/V转换电路；报警器

Abstract：Food storage is an effective measure of national preparedness for war, famine and other unforeseen incidents. So the safe of the grain storage is of great significance. In response to the needs of the Level detection for foods storage, this paper describes an intelligent detection system which is based on a two-capacitance sensor. The use of the two-capacitance sensor technology eliminates the interference factors of temperature, humidity and other factors in the detection system, which adapts to the harsh industrial environment. Meanwhile , based on the AT89C51 microcontroller, the system are made up of the double-Level capacitive sensor , the detection circuit of sensor signals, CPU and display circuits, alarm circuits and system software.

Key words: two-capacitance sensor; single chip processor; Small measurement circuit of capacitance; C/V converting circuit; annunciator

目 录
1 绪论 1
1.1 课题背景 1
1.2 粮仓料位检测的目的和意义 1
1.3 国内外料位监测的发展现状 2
1.4本论文的研究内容 2
2 电容式料位传感器原理、应用及发展 3
2.1 电容式料位传感器 3
2.1.1 电容式料位传感器的基本原理 3
2.1.2 目前电容式料位传感器存在的问题与不足 4
2.1.3 电容式料位传感器的改进和其发展趋势 5
3 粮仓料位智能检测系统 5
3.1电容式传感器的设计 5
3.2系统设计方案的确定 7
4 系统硬件电路设计 8
4.1 正弦激励源电路 8
4.2信号检测电路 8
4.3数据采集电路设计(A/D) 9
4.4 显示电路的设计 12
4.5 报警系统电路设计 13
4.6 看门狗电路设计 14
5 系统软件实现 15
5.1 主程序 16
5.2 数据采集子程序 16
5.3 显示子程序 17
6 结论 18
参考文献 18