【正文】 畢 業(yè)設(shè)計(jì) 說(shuō)明書(shū)（論文） 中文摘要 本系統(tǒng)是利用 AT89C52 為處理器，集合 DS1302 時(shí)鐘芯片、 DS18B20 溫度傳感器、水位傳感器等構(gòu)成的多功能太陽(yáng)能熱水器控制系統(tǒng)。該系統(tǒng)能夠測(cè)量并顯示實(shí)時(shí)水溫 、 水箱內(nèi)實(shí)時(shí)水位。具備自動(dòng)上水和手動(dòng)上水的功能，能夠根 水箱內(nèi)實(shí)時(shí)水位 決定是否上水，水滿自動(dòng)關(guān)閥并報(bào)警。 控制系統(tǒng)變換器部分的傳感器制作簡(jiǎn)單，安裝方便，經(jīng)濟(jì)實(shí)用。系統(tǒng)采用 4N26光電耦合器進(jìn)行光電隔離，增強(qiáng)系統(tǒng)抗干擾功能，保證系統(tǒng)安穩(wěn)準(zhǔn)確運(yùn)行。本說(shuō)明書(shū)詳細(xì)地闡述了系統(tǒng)設(shè)計(jì)原理，以及給出整體系統(tǒng)的原理框圖和電路圖。 關(guān)鍵詞 變換器 ， DS18B20， 電阻式 傳感器 畢業(yè)設(shè)計(jì) 說(shuō)明書(shū)（論文） 外文摘要 Title The Solar Water Heater Water Feeding Control System —— Converter Part Abstract Composed of set AT89C52 single processor, chip clock DS1302, temperature sensor DS18B20, The system is a multifunctional solar water heater control system,can measure and displays realtime water temperature, and water tanks in realtime. With automatic and manual water function, can root tank container, realtime water level determine whether water full automatic closing valves and alarm. The control system use simple part converter, and easy to be installed, economic and practical. The system uses 4N26 photoelectric coupler for photoelectric isolation, enhance the system antiinterference function to ensure that the system is safe accurate operation. This manual and expounds the system design principle, and gives overall system principle diagram and diagram. Keywords converter, DS18B20, resistive sensor 第 I 頁(yè) 共 Ⅱ 頁(yè) 目 錄 1 引言 ................................................................................................................................ 1 太陽(yáng)能熱水器的國(guó)內(nèi)外發(fā)展現(xiàn)狀 ............................................................................. 1 市場(chǎng)上各類熱水器的特點(diǎn) ......................................................................................... 2 課題研究的目的和意義 ............................................................................................. 3 課題研究的問(wèn)題和設(shè)計(jì)思路 ..................................................................................... 3 2 太陽(yáng)能熱水器上水控制系統(tǒng)總體設(shè)計(jì) ........................................................................ 3 系統(tǒng)方案設(shè)計(jì)原理 ..................................................................................................... 3 數(shù)據(jù)信息采集與轉(zhuǎn)換 ................................................................................................. 4 水位信號(hào)采集 .......................................................................................................... 4 溫度信息采集 .......................................................................................................... 5 時(shí)鐘 —— DS1302..................................................................................................... 7 單片機(jī)選擇 .................................................................................................................. 9 ATC89C52 單片機(jī) .................................................................................................... 9 鍵盤設(shè)計(jì)與顯示電路 ............................................................................................... 10 非編碼鍵盤的控制方式 ........................................................................................ 11 非編碼鍵盤接口設(shè)計(jì) ............................................................................................ 11 顯示設(shè)計(jì) ................................................................................................................ 11 光電隔離 ................................................................................................................... 12 太陽(yáng)能熱水器上水 控制系統(tǒng)上水電磁閥的選用 ................................................... 12 報(bào)警電路設(shè)計(jì) ........................................................................................................... 13 3 變換器部分設(shè)計(jì) .......................................................................................................... 14 電容式水位傳感器 ................................................................................................... 14 調(diào)頻電路 ................................................................................................................ 14 交流電橋電路 ........................................................................................................ 15 雙 T 型充放電網(wǎng)絡(luò) ............................................................................................... 16 運(yùn)算放大器電路 .................................................................................................... 18 差動(dòng)脈沖調(diào)寬電路 ................................................................................................ 18 電阻式水位傳感器 ................................................................................................... 21 電阻式水位傳感器原理 ........................................................................................ 21 測(cè)量電路 ................................................................................................................ 23 方案比較 ................................................................................................................... 24 電磁閥驅(qū)動(dòng)電路 ....................................................................................................... 25 4 控制器電源設(shè)計(jì) .......................................................................................................... 25 直流電源設(shè)計(jì) ..........................................................................