【正文】 1 安徽工業(yè)大學 畢業(yè)設(shè)計 (論文 )任務書 課題名稱 反應釜的溫度控制系統(tǒng) 學 院 電氣信息學院 專業(yè)班級 儀表 093 姓 名 鄒貴章 學 號 099064035 2 摘要 反應釜是化工生產(chǎn)過程中的重要設(shè)備，反應過程中伴隨有大量的吸、放熱現(xiàn)象，具有大滯后、時變、非線性、反應機理復雜等特點 . 傳統(tǒng)的 PID控制是一種基于過程參數(shù)的控制方法。具有控制原理簡單、穩(wěn)定性好、可靠性高、參數(shù)易調(diào)整等優(yōu)點，但其設(shè)計依賴于被控對象的精確數(shù)學模型，在線橄定參數(shù)的能力差，而反應釜因為機理復雜、各個參數(shù)在系統(tǒng)反應過程中時變，不能建立精確的數(shù)學模型，不能滿足系統(tǒng)在不同條件下對參數(shù)自整定的要求，因而采用一般的 PID控制器無法實現(xiàn)對反應釜的精確控制。 模糊控制是一種基于規(guī)則的語言控制，在設(shè)計中不需要建立被控對象的精確數(shù)學模型，魯棒性強，干擾和參數(shù)變化對控制效果的影響被大大減弱，控制效果好。但模糊控制器是以誤差和誤差變化作為輸入變量，這種控制器具有模糊比例一微分控制作用，精度不太高、穩(wěn)態(tài)誤差較大、自適應能力有限和易產(chǎn)生振蕩現(xiàn)象。 預測控制是一 種優(yōu)化控制算法，它是通過對某一性能指標的最優(yōu)來確定未來的控制作用的，具有對模型要求低、魯棒性好、適用于數(shù)字計算機控制的優(yōu)點。由于計算機模型預測控制具有良好的跟蹤性能，能有效地提高系統(tǒng)的穩(wěn)定性和消除誤差，對滯后過程有明顯控制效果，更加符合工業(yè)溫度控制的實際要求，從而大大提高了溫度控制系統(tǒng)的性能。 本文比較全面的分析了反應釜溫度變化的特點以及控制難點，總結(jié)當前溫度控制系統(tǒng)精度差的根本原因，在此基礎(chǔ)上采用基于預側(cè)的模糊自整定 PID集成控制技術(shù)實現(xiàn)反應釜溫度控制，其主要思想是利用系統(tǒng)模型的預測輸出，結(jié)合常規(guī) PID的控制經(jīng)驗，采用模糊推理方法，對控制器算法進行改進。實驗結(jié)果表明，與通常的 PID控制方案相比，該方案提高了系統(tǒng)的魯棒性和適應性，較好的解決了反應釜溫度控制的難題。 課題完成了反應釜溫度控制系統(tǒng)的硬件電路的設(shè)計、系統(tǒng)軟件的編譯與調(diào)試，對基于預測的模糊自整定溫度控制系統(tǒng)進行了仿真與實驗研究，與 PID控制方法相比，控制性能更加穩(wěn)定，可靠性更高，實時性、適應性、魯棒性都顯著增強，控制效果較好。 關(guān)鍵詞 :反應釜，預鍘控制，模糊控制， PID控制 3 Abstract Reactor is the important equipment in the process of chemical production, the chemical reaction acpanied by phenomenon whereby heat is liberated or absorbed, having characteristics of large time delay, timevarying, nonlinear, and the plicate d reaction mechanism. Traditional PID control is a control method based on process parameter, having many advantages of a simple control principle, good stability, high reliability and easy adjustment of parameters. But the design of the abject depends on the precise mathematical model and bad at tuning parameter online. The mechanism of reactor is plex and every parameter changes in the reaction process, unable to establish a precise mathematical model and it can not meet the requirements of selftuning under different conditions. So the general PID controller can not be achieved on the precise control of reactor. Fuzzy control is a rulebased language control, the precise mathematical model does not need to be established in the design and with good robustness, the effect that interference and the changes of parameters have on the control result is greatly reduce ,with effective Control. However , the fuzzy controller takes error or error change for input variables and this controller has fuzzy proportiondifferential control talc. The accuracy is too high, with a larger steadystate error, limited adaptive ability and easy oscillation. Predictive control is an optimal control algorithm, which determines the future control role by optimization of a performance index。 having advantages of low model, good robustness, applicability to the merits of digital puter control. The predictive control of puter model has a good tracking performance, and it can effectively improve system stability and eliminate the error, has significant control result for lag process, more in line with the actual industrial temperature control requirements, so it greatly improves the performance of temperature control system. In this paper, the characteristics and control difficulty of reactor temperature change are analyzed, and the root causes of poor accuracy for the current temperature control system is summarized, on the basis ,a technology of fuzzy selftuning PID control based on prediction is used to achieve reactor temperature control. The main idea is to use the prediction output of system model, bined with the experience of conventional PID control, using fuzzy reasoning algorithm to improve the algorithm of controller. The experimental results show that the PID control scheme, pared to the mon PID control scheme, can improve the system robustness and adaptability, with a better solution to the reactor temperature control problem. 4 This subject pletes the hardware circuit design of the reactor temperature control system, the pilers and debugging of system software. Simulation and experimental study are done for fuzzy selftuning PID control based on prediction, pared to the PID control method, the method has more stable control performance, higher reliability and the tealtime performance,adaptability, robustness are significantly increased. The control result is better. Keywords: Reactor, predictive control, fuzzy control, PID control. 5 目錄 摘要 ................................................................................................................................. 2 Abstract ............................................................................................................................ 3 第 1 章 緒論 ............................................................................................................... 7 國內(nèi)外化工控制發(fā)展現(xiàn)狀 ................................................................................ 7 控制方案的設(shè)計及不足 .................................................................................... 8 本課題采用的方案及內(nèi)容 ................................................................................ 8 本論文結(jié) 構(gòu)安排 ............................................................................................... 9 第 2 章 溫度控制系統(tǒng)方案 ........................................................................................ 10 微機控制系統(tǒng)簡介 ........................................................................................ 10 微機控制系統(tǒng)分類 .............................................................................. 10 微機控制系統(tǒng)硬件 .............................................................................. 11 微機控制系統(tǒng)軟件 .............................................................................. 11 PID 及新型 PID 控制算法簡介 .........................