51单片机的室内空气质量检测系统设计论文定稿

基于单片机的气体质量检测系统的设计摘 要本论文讨论设计了一种用于公共场所与室内具有检测与超限报警功能的室内空气质量检测系统。其设计方案基于 89C51 单片机，选择瑞士蒙巴波公司的 CH20/S-10 甲醛传感器和 MQ-5 气体传感器。系统将传感器输出的4~20mA 的标准信号通过以 AD0832 为核心的 A/D 转换电路调理后，经由单片机进行数据处理，最后由 LCD 显示甲醛浓度值。文中详细介绍了数据采集子系统、数据处理过程以与数据显示子系统和报警电路的设计方法和过程。系统对于采样地点超出规定的甲醛容许浓度和天然气规定浓度时采纳三极管驱动的单音频报警电路提醒监测人员。同时，操作人员对于具体报警点的上限值可以通过单片机编程进行设置。 另外，该系统对浓度信号进行了信号补偿等处理，减少了测量误差，因此，具有较高的测量精度，而且结构简单，性能优良。本系统的量程为 0-10ppm，精度为 0.039ppm 。关键词: 甲醛检测/天然气检测/AT89C52 单片机ABSTRACTThis thesis design of a paper for public places and indoor testing and over-limit alarm functions with indoor air quality testing system. Its design is based on 89C51 single chip, with the choice of MQ-5 gas sensors and CH20/S-10 formaldehyde sensor from Switzerland mengbabo pany. Sensor system will output 4 ~ 20mA standard signal through the core ADC0832 for A / D conversion circuit after conditioning, by the single-chip microputer for data processing, at last display the formaldehyde concentration on the LCD . The article detailed the data acquisition subsystem, data processing and data display and alarm system circuit design method and process.When the sampling sites when the formaldehyde and Natural gas concentration exceeded ， To the single-transistor drive circuit audio alarm will sound the alarm ， Testing staff to remind.At the same time ， The concentration of formaldehyde, Can be set through the single-chip programming. In addition, the system signals a concentration pensation signal processing, a...