长沙航空职业技术学院（2012届）
毕业生毕业设计（论文）
基于单片机的热水器温度控制系统设计
系 别：专 业：
姓 名：班 级： 学号： 指导老师姓名： 职称： 最终评定成绩：
2012年5月
长沙航空职业技术学院2012届毕业生毕业设计（论文） 摘要
温度是一种最基本的环境参数，人们生活与环境温度息息相关；在工业生产中也离不开温度的检测和控制。随着国民经济的发展，人们需要对各种加热器、热处理炉、反应炉和锅炉的温度进行检测和精确控制。因此研究温度的检测和控制具有重要的意义。
本论文介绍了一种基于AT89S52单片机为主要控制器件，以DS18B20为温度传感器的热水器温度控制系统。本系统通过DS18B20实时检测电热棒所加热的水温温度，由单片机从DS18B20读取出所测量出的温度数值，然后通过软件程序进行判断，控制固态继电器SSR的通断，再控制加热棒是否加热，从而实现实时检测并精准控制水温的目的。利用软件编程和外围电路，结合智能温度传感器DS18B20，通过按键能够任意设置温度上下限报警。显示电路采用四位LED共阴数码管来显示检测的水温数值。
本系统可以方便的实现温度的检测控制和显示，具有精度高、量程宽、灵敏度高、体积小、功耗低等特点，适用于我们的日常生活和工、农业生产中的温度检测控制领域。同时，也可以当作温度处理模块，嵌入到其他系统中，作为其他主系统的辅助扩展。本系统结构简单，抗干扰能力强，适合在恶劣环境下进行现场温度检测控制，具有广泛的应用前景。
关键词： AT89S52 DS18B20 温度控制 固态继电器
Abstract
Temperature is one of the most fundamental environmental parameters,people's lives and is closely related to the ambient temperature; temperature detection and control in industrial production is also inseparable. With the development of the national economy, people need to detect and precisely control the temperature of the various heaters, heat treatment furnaces, reactors and boilers. Therefore, the temperature detection and control of the study has important significance.
This paper describes the water heater temperature control system based on AT89S52 microcontroller as the main control device,DS18B20 as the temperature sensor. The water temperature is the temperature of the system through the the DS18B20 real-time detection of electric heating rods are heated by the microcontroller from the DS18B20 read out the measured
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长沙航空职业技术学院2012届毕业生毕业设计（论文） temperature values, and then be judged by a software program, on-off control Solid State Relay (SSR), to control whether the heating rods heating , in order to achieve real-time detection and precise water temperature control purposes. Software programming and peripheral circuits, combined with intelligent temperature sensor DS18B20 were able to set upper and lower temperature alarm button. Common cathode circuit uses four LED digital tube to detect the water temperature value is displayed.
The system can facilitate the detection of temperature control and display, with high accuracy, wide range, high sensitivity, small size, low power consumption, applies to our daily life and work, the temperature in the agricultural production in the field of detection and control. Meanwhile, it is also can be used as the temperature of the processing module, embedded into other systems, as the auxiliary expansion of other primary system. The system structure is simple, strong anti-jamming capability, suitable for use in harsh environments, the scene temperature detection control, has a broad application prospects.
Keywords: AT89S52 DS18B20 temperature control solid state relay
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长沙航空职业技术学院2012届毕业生毕业设计（论文） 目录
目录 ............................................................................................................................ 4 第1章 绪论 .............................................................................................................. 6 1.1课题研究背景 ..................................................................................................... 6 1.2温度控制系统的发展现状 ................................................................................. 7 1.3系统设计要求 ..................................................................................................... 8 第2章 系统总体方案设计与论证 .......................................................................... 9 2.1系统微处理器方案的选择与论证 ..................................................................... 9 2.2温度检测模块电路方案的选择与论证 ............................................................. 9 2.3温度控制模块电路方案的选择与论证 ........................................................... 10 2.4温度设置模块电路方案的选择与论证 ........................................................... 11 2.5温度显示模块电路方案的选择与论证 ........................................................... 12 2.6加热器方案的选择与论证 ............................................................................... 13 第3章 系统总体框图设计 .................................................................................... 13 3.1系统硬件框图设计 ........................................................................................... 13 第4章 系统硬件模块电路设计 ............................................................................ 14 4.1系统电源模块电路设计 ................................................................................... 14 4.2单片机最小系统模块电路设计 ....................................................................... 14 4.3温度检测模块电路设计 ................................................................................... 16 4.3.1温度传感器DS18B20的介绍 .................................................................... 16 4.4温度控制模块电路设计 ................................................................................... 18 4.5温度设置模块电路设计 ................................................................................... 18 4.6温度报警模块电路设计 ................................................................................... 19 4.7温度显示模块电路设计 ................................................................................... 20 第5章 系统软件设计 ............................................................................................ 20 5.1系统软件主程序设计 ....................................................................................... 20 5.2温度读取子程序设计 ....................................................................................... 22 5.3温度计算子程序设计 ....................................................................................... 23 5.4温度转换命令子程序设计 ............................................................................... 23 5.5显示数据刷新子程序设计 ............................................................................... 24 5.6按键扫描处理子程序设计 ............................................................................... 25 第6章 系统仿真调试 ............................................................................................ 26 6.1仿真软件Proteus简介 ................................................................................... 26 6.2系统仿真调试过程 ........................................................................................... 27 6.3系统仿真调试结果 ........................................................................................... 29 设计总结 .................................................................................................................. 30 致谢 .......................................................................................................................... 31
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长沙航空职业技术学院2012届毕业生毕业设计（论文） 参考文献 .................................................................................................................. 33 附录1 原理图与PCB图 ......................................................................................... 34 附录2 元器件清单 ................................................................................................. 36 附录3 参考程序 ..................................................................................................... 37
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