基于单片机的可燃气体探测报警控制系统

河南科技学院新科学院2014届本科毕业论文（设计）基于单片机的可燃气体探测报警控制系统学生姓名：侯青青所在院系：新科学院电气工程系所学专业：电子信息工程导师姓名：王红军完成时间：2015年4月10日基于单片机的可燃气体探测报警控制系统摘要随着电子科学技术的进步和发展，电子技术逐渐成为安全方面的有力手段，许多安全方面的电子产品，是人们在生活中的得力助手。本设计利用单片机技术结合A/D转换芯片构建了一个可燃气体探测报警系统。当环境中可燃气体泄露并达到一定浓度时，可燃气体报警报警系统将会检测到并发出报警信号，以提醒工作人员采取安全措施。本文首先简要介绍了可燃气体探测报警控制系统的主要方式以及单片机系统的优势，后又详细地介绍了可燃气体探测报警控制系统的设计流程，以及硬件系统和软件系统的设计，给出了硬件电路的设计细节，包括各个部分电路、芯片的选择、方案的可行性分析等。本系统主要由传感器MQ-2、单片机AT89C52、模数转换芯片ADC0808、液晶显示屏LCD1602构成，其功能是对环境中可燃气体的浓度进行监测，当浓度达到原本设定的报警值时，就会触发声光报警。其主要工作流程为：首先由传感器MQ-2对环境中有害气体的浓度进行采集，然后将其转化为相应的电压值，将模拟信号采集处理后传送给模数转换芯片ADC0808，再将转换后的数字信号传送给单片机AT89C52，单片机内部建立浓度与电压的关系，将结果送入LCD进行显示，若可燃气体浓度达到报警值时会触发声光报警，从而能够降低日常生活中可燃气体泄漏所引起的事故的发生。关键词：单片机，可燃气体，MQ-2传感器DesignofIgnitableGasAlarmDetectorandControllerBasedonMCUAbstractWiththeprogressanddevelopmentofelectronicscienceandtechnology,electronictechnologyhasbecomethepowerfultoolsforthesecurity,manysecurityelectronicproducts,ispeopleinlife'sright-handman.ThisdesignusingthesinglechipmicrocomputertechnologycombinedwiththeA/DconversionchipbuiltAcombustiblegasdetectionalarmsystem.Whenthecombustiblegasleakageintheenvironmentandachieveacertainconcentration,combustiblegasalarmalarmsystemwillbedetectedandsignalalarm,toremindstafftotakesafetyprecautions.Thispaperfirstbrieflyintroducesthemainwayofcombustiblegasdetectionalarmcontrolsystemandtheadvantageofsinglechipmicrocomputersystem,andintroducesindetailthedesignprocessofthecontrolsystemofflammablegasdetectionalarm,andthedesignofhardwaresystemandsoftwaresystem,detailsthedesignofhardwarecircuitaregiven,includingtheselectionofeachpartofthecircuit,chip,projectfeasibilityanalysis,etc.MQ-2thissystemismainlycomposedofsensor,microcontrollerAT89C52,modulusconversionchipADC0808,LCDdisplayLCD1602,itsfunctionistotheconcentrationofthecombustiblegasinenvironmentmonitoring,whentheconcentrationreachesoriginallysetalarmvalue,willtriggerasoundandlightalarm.Itsmainworkingprocessis:firstbythesensorMQ-2toacquisitionoftheconcentrationofharmfulgasintheenvironment,andthentranslatethemintocorrespondingvoltagevalue,theanalogsignalcollectionandprocessingwillbesenttoADC0808modulusconversionchip,thentheconverteddigitalsignaltransmittedtothesinglechipmicrocomputerAT89C52,MCUinternalbuildrelationsbetweentheconcentrationandvoltage,theresultsintotheLCDdisplay,ifcombustiblegasconcentrationreachesthealarmvalue,willtriggertheacousto-opticalarmsothattheycanreducedailylifecausedbycombustiblegasleakageaccidents.Keywords:AT89C52,combustiblegas,MQ-2sensorI目录绪论..................................................................................................................................................11报警器的概述.............................................................................................................................11.1报警器的研究背景及意义........................................................................................................11.2气体传感器的分类....................................................................................................................22系统组成框图与工作原理...........................................................................................................23主要原件介绍...............................................................................................................................33.1STC89C52单片机.....................................................................................................................33.1.1概述.........................................................................................................................................33.1.2管脚介绍.................................................................................................................................33.1.3最小系统..................................................................................................................................53.2转换芯片ADC0808.....................................................................................................................63.2.1概述.........................................................................................................................................63.2.2管脚介绍.................................................................................................................................73.3气体传感器MQ-2.......................................................................................................................83.4液晶显示模块............................................................................................................................94电路单元硬件设计.......................................................................................................................94.1可燃气体信号采集部分电路....................................................................................................94.2A/D转换部分电路.................................................................................................................104.3显示部分电路..........................................................................................................................114.4报警电路......