【作者】 袁飞；

【导师】 卢文科；

【作者基本信息】 东华大学 ， 控制理论与控制工程， 2010， 硕士

【摘要】 随着可燃性气体应用范围的增加,可燃性气体的泄漏事故日益增多。若泄漏的可燃性气体未被及时发现,而使其浓度不断增加,当到达一定的爆炸极限是就可能引起火灾爆炸事故,对生命财产造成严重的危害。因此,研制一种性能稳定、测量精度高的可燃性气体探测器是十分必要的。根据设计要求和成本等因素,本文选用KC-1型催化燃烧式可燃气体传感器对可燃性气体的浓度进行检测。采用ATmega128型单片机作为中央处理单元,完成对浓度信号的采集、处理、显示以及报警等工作。本文详细的阐述了可燃性气体探测器的软件和硬件设计。介绍了直流稳压电源、安全栅、前置放大电路的设计。并且根据本质安全电路的要求,对处于危险场所中的电路的每一个结点进行检验,以确保电路的本质安全性。防止因为电路设计不当而引起爆炸。文中还介绍了核心芯片的选型,以及外围电路和主要流程图的设计。外围电路主要包括故障自诊断电路、单片机接口电路、声音报警电路、状态指示灯电路和浓度显示电路。系统软件流程主要分为主程序、初始化子程序、故障自诊断子程序、浓度显示子程序、报警子程序等。本文设计的本质安全型可燃性气体探测器可以对空气中可燃性气体的浓度进行实时的检测,并且将浓度值显示在仪表盘上。当空气中的可燃性气体浓度值达到或超过限定浓度时,报警器发出报警。通过实验表明,该探测器可以实时准确的检测可燃性气体的浓度值,并且运行稳定,有较高的实用价值。更多还原

【Abstract】 With the rapid increase of combustible gas applied range, the leakage of combustible gas is more often. If combustible gas is not detected immediately and accumulates to the blast limit, it can lead to fire and blast. It can endanger the property and human life. So it is necessary to develop a new type of combustible gas detector.According to the design requirements, cost and other factors, we choose the KC-1 catalytic combustion gas sensor to measure the concentration of combustible gas. We choose ATmega128 as the core part of combustible gas alarm instrument. It is used to get, process and display the signal.This paper discusses the combustible gas detector instrument hardware circuit and software program design in detail, introduces the design of the DC power supply, the safety barrier and the preamplifier. And to ensure that the circuits are safe, we check the every node in the circuits. This paper also introduces the core chip, interface with external circuit and central flow chart. The hardware circuit mainly includes malfunction self-diagnosing circuit, MCU interface circuit, sound alarm circuit, light control circuit and display circuit. The applied software are composed by main program flow, initial subprogram flow, malfunction self-diagnosing subprogram flow, concentration disposal subprogram flow, alarm subprogram flow and so on.This combustible gas detector can detect the concentration of combustible gas, and displays the value of concentration on the instrument. When combustible gas reaches alarm threshold value, the instrument sends out sound and light alarm. The combustible gas detector instrument has got past the test and got a satisfying result. It has a high practical value.更多还原