基于单片机的天然气泄漏检测系统设计

基于单片机的天然气泄漏检测系统设计

摘要

随着经济和科学技术的快速发展，人们对生活质量的提高和生活环境的改善越来越重视。天然气作为一种清洁型能源进入家庭得到广泛使用，为人们的生活带来了方便，减少了城市的污染，提高了生活质量和效率，但是同时，天然气也是潜在的“危险品”，天然气在使用过程中，若管道和阀门密封不好，一旦泄漏出去极易爆炸，危及人们的生命财产安全。面对燃气泄漏而造成的种种事故威胁，我们需要一个解决办法。然而使用天燃气检测系统成为了一个重要的研究课题。

本毕业设计的题目是基于单片机的天然气泄漏检测系统设计。本设计主要是由一个MQ-4传感器采集气体浓度信号，系统建立浓度与电压关系，进行浓度电压转换，浓度显示，声光报警构成的报警装置。本系统由ADC0832处理数据，MCU采用STC89C52，完成气体浓度信号的采集显示内容的传输、显示等功能。本设计的可燃气体报警器由六个部分组成：传感器、数码管显示器、声光报警器、控制电路、A/D转换和电源模块。软件上采用C语言编程，结构简单运行稳定。

该检测系统能够检测天然气浓度，当检测天然气浓度低于设定报警阈值的时候，数码管显示器仅仅显示测得的可燃气体浓度；当检测天然气浓度超出设定报警阈值时给出声光报警，并伴有语音提醒。

关键词：MQ-4传感器；ADCO832；STC89C52；数码管；声光报警

Abstract

With the rapid development of economy and the science technology , people pay more and more attention to the quality of life and the improvement of living e nvironment. Natural gas are widely used in our daily life and brings convenience f or people's lives as a cleaner fuel, reduce the city's pollution and improve the life quality and efficiency.

but at the same time, natural gas is also potential dangerous, If not sealed pipes an d valves, they leaked,easily caused by fire ,endangering people's lives and property . Facing the gas leak all kinds of accidents caused by threats, we need a solution. And it is obviously very important to study on the inspection methods and sensor s of all kinds of gases.

This graduation design is a gas leak detection alarm system based on single chip microcomputer. This design mainly by an MQ - 4 gas concentration sensor acquisition signals, Concentration and voltage relations system,To convert the concentration of voltage, concentration of voltage conversion, concentration, according to the sound and light alarm alarm device.This system by ADC0832 processing data, use STC89C52 MCU, complete the gas concentration signal collection and display content transmission, display, and other functions.The design of the combustible gas alarm is composed of six parts: sensor,digital tube, sound and light alarm, control circuit, A/D conversion and power module.The software system is based on the C language programming, whose structure is simple and running stable.

This detection alarm system can detect the density of gas , When detecting gas concentration is lower than the set alarm threshold, digital tube display show only measured concentration of combustible gas; When detecting gas concentration exceeds the alarm threshold acousto-optic alarm.

Keywords：MQ-4；ADC0832；STC89C52；Digital tube；Sound and light alarm

目录

摘要 (1)

Abstract (2)

绪论 (1)

1基于单片机的天然气泄漏检测系统概述 (2)

1.1天然气泄漏检测报警器的概述 (2)

1.2家用天然气泄漏检测报警器现状 (2)

1.3家庭燃气泄漏报警的发展趋势 (2)

1.4天然气泄漏检测报警设计意义 (3)

2天然气泄露检测报警系统的方案设计 (4)

2.1天然气泄漏检测报警系统简介 (4)

2.2气体传感器的选型 (4)

2.3 天然气泄露报警系统的整体设计方案 (5)

2.3.1天然气泄漏报警器工作原理 (5)

2.3.2天然气泄漏报警器的结构 (5)

2.3.3报警器各模块的功能 (6)

3天然气泄露报警的硬件部分设计 (7)

3.1主控电路设计 (7)

3.1.1STC89C52单片机简介 (7)

3.1.2 STC89C52单片机的基本结构 (7)

3.1.3 STC89C52RC单片机的引脚 (8)

3.2电源电路设计 (10)

3.3可燃气体信号采集部分 (11)

3.4 MQ-4气体传感器 (11)

3.5 A/D转换部分 (13)

3.5.1 A/D转换电路 (13)

3.6 气体结果测量计算 (15)

3.7 声光报警部分 (15)

3.8 计数器译码显示电路 (16)

3.8.1 LED 的综述 (16)