唐 山 学 院
毕 业 设 计
设计题目：基于单片机的锅炉温度控制系统的设计与实现
系 别： 信息工程系 班 级： 12电气工程及其自动化（2）班 姓 名： 周雄 指 导 教 师： 廉文利
2016年
6月
1 日
唐山学院毕业设计
基于单片机的锅炉温度控制系统的设计
摘 要
根据对当前采暖需求情况广泛调查，目前的广大用户的采暖方式为燃煤锅炉的一次集中供暖，就能源方面的而言，集中燃煤供暖对能源的利用率相对比较低，消耗大，就实际供暖效果而言，燃煤供暖对有的用户供暖过热的时候，而有的用户却没有达到理想的供暖效果。结合工程实际需要，针对燃气锅炉的特点，研制开发了基于MCS-51单片机的小型家用燃气锅炉蒸汽温度控制系统，其目的在于改善燃煤锅炉集中采暖时所遇到的锅炉温度不易控制，改进采暖的控制方式，提高采暖的经济性、实用性。这种采暖方式的目的是将每一位需要供暖的用户都看成一个独立的个体，针对性的供暖。本设计主要利用 Protues电路设计软件，对智能控制器的电源电路、复位电路、时钟电路、报警电路、LCD液晶显示电路，以及控制器温度采集电路进行了设计。电源采用三端集成稳压器W7800或者W7900系列元件7805,交流220 V电压转换成为MCS-51单片机所需要的5V电压；将AT89S51作为控制器的核心器件；利用集成电路温度传感器DS18B20测量锅炉水温;将测量的水温与预先设定的设定值进行比较，单片机另外使用LCD液晶显示器显示水位的上下限值、当前水位、预先设定的温度报警值、当前采集的温度值。当测量的温度超过设定的报警温度值时，系统会发出报警声音，同时关闭锅炉燃烧器。然后等待温度降到下限值，这时就可以重新对锅炉燃烧器进行通电，继续加温，如此反复监控温度。这样就可以节约能源，提高能源的使用率。针对该系统的要求和特点，在上述硬件电路及实现方法的基础上，利用汇编语言，设计了基于单片机的锅炉蒸汽温度控制系统。控制软件主要包括温度和温度采集子程序、键盘扫描子程序和LCD液晶显示子程序等。通过对温度的测试，可以发现所设计的控制系统能够满足设计要求，并达到理想的效果。
关键词：单片机；LCD；燃气锅炉；温度控制；DS18B20
唐山学院毕业设计
Microcontroller-based design of the boiler
temperature control system
ABSTRACT
According to the current heating demand extensive investigation, current users of heating coal-fired boiler central heating, energy, coal-fired heating energy utilization rate is relatively low, consumption, the actual heating effects, coal-fired heating for some users heating overheating, and some users has not reached the ideal heating effect. Combined with the actual needs of the project, according to the characteristics of gas boiler and developed based on MCS-51 single chip microcomputer small household gas boiler steam temperature control system, its purpose lies in encountered improve coal-fired boiler central heating boiler temperature is not easy to control, improved the control mode of heating and improve the heating is economic and practical. The purpose of this kind of heating way is to be regarded as an independent individual, for the purpose of heating. This design mainly uses Protues circuit design software, the intelligent controller power supply circuit, reset circuit, clock circuit, alarm circuit, LCD display circuit, and a controller temperature acquisition circuit is designed. Power supply using three terminal voltage regulator integrated w7800 or W7900 series element 7805, AC 220 V voltage into a MCS-51 microcontroller need 5V voltage; the AT89S51 as the core chip of the controller; the use of integrated circuit temperature sensor DS18B20 measuring boiler water temperature; will measure the temperature of the water with preset setting values were compared, MCU and LCD display to display the water level of upper and lower limit value, the current level and preset temperature alarm value, the collection of temperature value. When the measured temperature exceeds the set alarm temperature value, the system will send out alarm sound, and close the boiler burner. And then wait for the temperature to drop to the lower limit, then you can re boiler burner for electricity, continue to heat, so repeated monitoring temperature. This can save energy, improve energy efficiency. According to the requirements and characteristics of this system, the boiler steam temperature control system based on single chip microcomputer is designed, which is based on the hardware circuit and the realization method. Control software mainly includes temperature and temperature acquisition subroutine, keyboard scanning subroutine and LCD liquid crystal display subroutine, etc.. Through the test of temperature, it can be
唐山学院毕业设计
found that the designed control system can meet the design requirements, and achieve the desired results
Keywords:MCU; Liquid Crystal Display; Gas boiler; Temperature control;DS18B20
唐山学院毕业设计
目录
1 引言 ................................................................................................................................... 1
1.1 课题背景及研究意义 ............................................................................................. 1 1.2 系统的总体设计思想 ............................................................................................. 2 2 系统方案论证及工作原理 ............................................................................................... 3
2.1 设计方案论证 ......................................................................................................... 3 2.2 系统结构框图 ......................................................................................................... 3 2.2.1主要器件的选择 ................................................................................................... 5 2.2.2 锅炉辅助器件选择 .............................................................................................. 5 3 硬件电路设计 ................................................................................................................... 6
3.1 主电路 ..................................................................................................................... 6 3.2单片机选择设计 ...................................................................................................... 7 3.3 单片机最小系统 ..................................................................................................... 9
3.3.1时钟电路设计 ................................................................................................ 9 3.3.2 复位电路 ....................................................................................................... 9 3.4温度检测电路设计及温度传感器选择 ................................................................ 10
3.4.1 DS18B20简介 ............................................................. 错误！未定义书签。 3.4.2温度采集电路 .............................................................................................. 11 3.5 温度控制电路设计 ............................................................................................... 12 3.6 水位控制电路 ....................................................................................................... 12 3.6 显示电路设计 ....................................................................................................... 13 3.7 报警电路设计 ....................................................................................................... 16 3.8 稳压电源电路设计 ............................................................................................... 17 3.9按键电路的设计 .................................................................................................... 17 4 系统软件设计 ................................................................................................................. 19
4.1主流程图设计 ........................................................................................................ 19 4.2中断程序程序 ........................................................................................................ 21 4.3 DS18B20温度采集子程序设计 ........................................................................... 21 4.4 LCD液晶显示子程序设计 ................................................................................... 23 总 结 ................................................................................................................................... 24 致谢 ..................................................................................................................................... 25 参考文献 ............................................................................................................................. 27
附录：总程序 .............................................................................................................. 28