單片機(jī)電加熱爐溫度控制系統(tǒng)

目 錄
第1章 緒 論 1
1.1 溫度控制系統(tǒng)的發(fā)展?fàn)顩r 1
1.2 本次設(shè)計(jì)的主要內(nèi)容 1
第2章 系統(tǒng)的基本原理及性能指標(biāo) 3
2.1 系統(tǒng)基本原理 3
2.2 預(yù)期達(dá)到的性能指標(biāo) 3
第3章 溫度控制系統(tǒng)的硬件設(shè)計(jì) 5
3.1 溫度檢測(cè)電路及元器件選擇 5
3.1.1 放大器AD522 5
3.1.2 橋式測(cè)量電路設(shè)計(jì) 6
3.2 單片機(jī)最小系統(tǒng)及外圍設(shè)備 7
3.2.1 系統(tǒng)電源電路設(shè)計(jì) 10
3.2.2 看門狗電路設(shè)計(jì) 11
3.2.3 系統(tǒng)時(shí)鐘電路設(shè)計(jì) 13
3.3 數(shù)據(jù)采集電路的設(shè)計(jì) 14
3.3.1 模數(shù)轉(zhuǎn)換器AD574 14
3.3.2 多路轉(zhuǎn)換開(kāi)關(guān)CD4051 16
3.4 鍵盤/顯示接口技術(shù)及報(bào)警電路 17
3.4.1 8279的電路組成和工作原理 18
3.4.2 管腳功能說(shuō)明 19
3.4.3 8279與鍵盤顯示器的連接 21
3.4.4 LED報(bào)警電路的設(shè)計(jì) 23
3.5 溫度控制電路設(shè)計(jì)及控制算法 23
3.5.1 控溫電路 23
3.5.2 系統(tǒng)控制算法設(shè) 24
第4章 溫控系統(tǒng)的軟件設(shè)計(jì) 26
4.1 軟件設(shè)計(jì)總體思想 26
4.2 軟件程序流程圖 26
4.2.1 主程序流程圖 26
4.2.2 鍵盤掃描和譯碼過(guò)程的流程圖 28
4.2.3 8通道數(shù)據(jù)采集的程序流程圖 29
4.2.4 單片機(jī)主程序流程圖 30
第5章 結(jié) 論 31
參考文獻(xiàn) 32
致 謝 34
附 錄Ⅰ 35
附 錄Ⅱ 49
附 錄Ⅲ 50

摘 要
隨著計(jì)算機(jī)技術(shù)、控制理論和控制技術(shù)的發(fā)展，電加熱爐的溫度控制日趨成熟，已經(jīng)成為工業(yè)生產(chǎn)中的一個(gè)重要部分。
為了適應(yīng)工業(yè)控制發(fā)展的需要，本文在分析單片機(jī)對(duì)電加熱爐溫度控制的 基礎(chǔ)上，從該系統(tǒng)的基本性能和基本操作出發(fā)，將整個(gè)系統(tǒng)分為溫度測(cè)量、A/D轉(zhuǎn)換、單片機(jī)系統(tǒng)、鍵盤操作系統(tǒng)、溫度顯示電路、報(bào)警電路、D/A轉(zhuǎn)換等若干個(gè)功能模塊。同時(shí)分別闡述其結(jié)構(gòu)體系、工作原理、設(shè)計(jì)、集成方法以及它們之間的共性和特點(diǎn)。由于溫控技術(shù)與自動(dòng)化技術(shù)的發(fā)展非常迅速，本文一方面結(jié)合實(shí)際應(yīng)用經(jīng)驗(yàn)，力求做到較為系統(tǒng)和全面的介紹系統(tǒng)設(shè)計(jì)與實(shí)施技術(shù)；另一方面盡可能反應(yīng)出溫控系統(tǒng)的發(fā)展趨勢(shì)，以及其先進(jìn)性和實(shí)用性。
本設(shè)計(jì)的控制對(duì)象為電加熱爐，通過(guò)控制加在電阻絲兩端電壓的工作時(shí)間，來(lái)對(duì)電阻絲輸出的平均功率加以控制。以單片機(jī)為核心，采用固態(tài)繼電器控溫電路，實(shí)現(xiàn)對(duì)電爐的自動(dòng)控制。本文將采用PID控制，闡述了PID控制器的設(shè)計(jì)，硬件結(jié)構(gòu)和軟件設(shè)計(jì)，實(shí)現(xiàn)了一套溫度采集和控制的方案。該系統(tǒng)具有硬件成本低，控溫精度較高，可靠性好，抗干擾能力強(qiáng)等特點(diǎn)。

關(guān)鍵詞：電加熱爐；單片機(jī)；溫度控制；固態(tài)繼續(xù)電器

Abstract
With the development of the technology of computer and control，the temperature control of electric heating furnace is becoming fully developed, the technology has been an important part of industry.
To meet the requirement of industrial control, the thesis designs a system which is constituted of temperature detecting device, A/D conversion, monolithic processor keyboard and display apparatus, alarming circuit and D/A conversion based on the control of electric heating furnace. The thesis explains the principle, the concept of design, constitution and characteristic. Because of the great developing speed of automatic temperature controlling, the thesis try to explain the system in detail, and the thesis also reflect the direction of the development of temperature controlling system.
This design controlled member is an electric heating stove, adds through the control in the resistance wire beginnings and ends voltage operating time operating time, comes the average power which outputs to the resistance wire to perform to control. Automatic temperature control of the electric furnace is realized by a temperature control circuit of solid state relay on the basis of the single-chip computer. This article put PID algorithm applies in the resistance furnace temperature control system, elaborated PID controller design, the hardware constitution and the software design, have realized set of temperatures gathering and the control design proposal. This control system has such advantages as low cost .control accuracy, good reliability and good resistance to interference.

Key words: electric heating furnace；single-chip computer；temperature control；solid state relay