高溫鹽浴爐溫度控制系統(tǒng)

論文編號:ZD1234   論文字?jǐn)?shù):16927,頁數(shù):45  附原理圖，外文翻譯

摘  要
                              
 鹽浴爐是熱處理車間的主要加熱設(shè)備之一，多用于零件的淬火、回火、正火等處理。目前使用的鹽浴爐大多采用的是分檔調(diào)節(jié)、人工控溫的落后辦法。這種控制方法能耗高、控溫精度差，而且爐溫波動大，噪聲大。電壓調(diào)節(jié)通過人工轉(zhuǎn)換無載分接開關(guān)機(jī)械觸電實(shí)現(xiàn)，造成無載分接開關(guān)容易燒壞，維修頻繁，并且溫度波動大，有時不能滿足某些工件的加工要求。
 為使之一設(shè)備能更加有效地工作，本文提出了對鹽浴爐控制系統(tǒng)進(jìn)行改造的方案。針對鹽浴變壓器只能進(jìn)行無載分接、有級調(diào)節(jié)的問題，本方案采取在變壓器原邊串接晶閘管的方法，將手動轉(zhuǎn)換的溫度控制，即無載分接開關(guān)機(jī)械觸點(diǎn)調(diào)節(jié)電壓改為單片機(jī)自動控制晶閘管的導(dǎo)通，將手動控制溫度改為PID控制，從而提高了控制精度，降低了工人勞動強(qiáng)度。
 針對鹽浴爐的非線性、變參數(shù)、大時滯，工作環(huán)境差，加工零件多樣的特點(diǎn)，本方案控制器采用PID控制算法。本文提出的PID控制算法。主要由數(shù)字PID調(diào)節(jié)構(gòu)成。PID控制算法提高了系統(tǒng)的自適應(yīng)能力和魯棒性，獲得了較好的控制穩(wěn)定性。還實(shí)現(xiàn)了生產(chǎn)過程參數(shù)的自動顯示和記錄、超溫報(bào)警、工件入爐、出爐提示等輔助控制功能。節(jié)約了維修時間和費(fèi)用。系統(tǒng)投入使用后，提高了產(chǎn)品質(zhì)量；節(jié)省了能源。

關(guān)鍵詞：鹽浴爐  PID控制  MPU

Abstract        
                                  
   Today, salt-bath stove is still one of the main heating equipments in the heat-treating workshops. The sale-bath stove employs presently generally adopt the backward method of gearshift adjusting and segment heat controlling. These methods of controlling consume too much power. It also has other demerits such as low precision and much noise. The voltage is manually regulated by non-load machine switch, which is apt to be burnt. As a result, frequent fixing is inevitable; moreover, these methods of controlling cannot meet the needs of processing certain work pieces.
   I this paper, transform approach is proposed for the salt-bath stove controlling system. In the
Approach, non-load machine switch is replaced by SCR controlled by MPU to regulate the temperature. This control precision is greatly improved, and at the same time parameters can be automatically stored and displayed during the manufacturing process, it also included some other auxiliary controlling functions, such as over-temperature alarm, work piece input or output reminding, etc. 
 The fuzzy PID control algorithm consists of fuzzy control and digital PID adjustment. The fuzzy controller can adjust the parameter of PID controller on line. The combination of fuzzy control and PID control would achieve fine function. The result of simulation and experiment show that the reformed automatic control system can gain upon higher product quality, less power consumption, less fixing time and expense, etc.
 
 
Keywords: Salt-bath stove   PID control   Micro-process Unit

目  錄

第一章 概述…………………………………………………………………………1
第二章 方案論證……………………………………………………………………2
第三章 高溫鹽浴爐控制系統(tǒng)的硬件設(shè)計(jì)…………………………………………5
3.1現(xiàn)場環(huán)境介紹……………………………………………………………………5
3.2總體設(shè)計(jì)…………………………………………………………………………5
3.3控制系統(tǒng)結(jié)構(gòu)……………………………………………………………………5
3.4元器件選擇………………………………………………………………………6
3.4.1 熱電偶…………………………………………………………………………6
3.4.2 A/D轉(zhuǎn)換器 ……………………………………………………………………7
3.4.3 89C51單片機(jī) …………………………………………………………………11
3.4.4LED顯示部分 …………………………………………………………………18
3.4.5 控溫電路………………………………………………………………………21
第四章 高溫鹽浴爐PID算法………………………………………………………25
4.1數(shù)字控制…………………………………………………………………………25
4.2數(shù)字PID控制算法………………………………………………………………26
第五章 高溫鹽浴爐軟件設(shè)計(jì)………………………………………………………28
5.1芯片間的通訊方式………………………………………………………………28
5.2 控制系統(tǒng)軟件設(shè)計(jì) ……………………………………………………………28
5.2.1 主程序…………………………………………………………………………28
5.2.2 子程序…………………………………………………………………………29
第六章 系統(tǒng)抗干擾的設(shè)計(jì)…………………………………………………………33
致謝………………………………………………………………………………… 34
參考文獻(xiàn)…………………………………………………………………………… 35
附表一………………………………………………………………………………36
附表二………………………………………………………………………………37
附表三………………………………………………………………………………