基于PLC的溫控系統開發

電氣自動化論文編號:ZD898    論文字數:13650,頁數:38

目 錄
摘要………………………………………………………………………………………………Ⅰ
Abstract………………………………………………………………………………………Ⅱ
目錄………………………………………………………………………………………………Ⅲ
1  緒論 …………………………………………………………………………………………1
 1.1  背景 ……………………………………………………………………………………1
 1.2  溫度智能控制平臺的總體概述 ………………………………………………………2
2  系統的硬件設計……………………………………………………………………………3
 2.1  松下PLC介紹………………………………………………………………………3
 2.2 FPΣ及擴展單元詳細介紹………………………………………………………………4
 2.2.1  FPΣ…………………………………………………………………………5
 2.2.2  FP∑及模擬量輸入模塊介紹………………………………………………… 7
    2.3  溫度采集電路  ………………………………………………………………………10
 2.4  電熱絲控制電路………………………………………………………………………12
3  系統軟件設計 …………………………………………………………………………13
 3.1  PID控制簡介………………………………………………………………………13
 3.1.1  PID控制的特點………………………………………………………………13
 3.1.2  PID控制原理…………………………………………………………………14
 3.1.3  PID控制算法的設計…………………………………………………………16
 3.1.4  參數的整定……………………………………………………………………18
 3.2 松下編程軟件介紹……………………………………………………………………17
 3.3  程序結構圖……………………………………………………………………………19
     3.3.1  主程序流程圖 ……………………………………………………………… 20
 3.4  程序設計………………………………………………………………………………20
 3.4.1  參數自整定程序………………………………………………………………21
 3.4.2  PID控制程序…………………………………………………………………23
 3.4.3  繼電器控制程序………………………………………………………………24
4  溫控系統平臺  …………………………………………………………………25
 4.1  溫度采集電路  ………………………………………………………………………25
 4.2  PLC連接電路  ………………………………………………………………………25
 4.3  電熱絲控制電路  ……………………………………………………………………26
 4.4  電熱絲  ………………………………………………………………………………26
 4.5  溫控系統整體  ………………………………………………………………………27
5  總結…………………………………………………………………………………………28
致謝………………………………………………………………………………………………29
參考文獻 ………………………………………………………………………………………30
附錄1  主要程序……………………………………………………………………………31

 摘  要
 溫度是工業對象中主要的被控參數之一，像冶金、機械、食品、化工各類工業中，廣泛使用的各種加熱爐、熱處理爐、反應爐等，對工件的處理溫度要求嚴格控制，因為它直接影響燃燒、化學反應、發酵、烘烤、煅燒、蒸餾、濃度、擠壓 成形，結晶以及空氣流動等物理和化學過程。隨著技術的發展，溫度控制系統的組成部分也在變化。本文介紹了以松下PLC為核心的溫度控制平臺的設計。并介紹了其軟、硬件設計的方法和給出了系統的硬件原理圖、軟件流程圖。在該設計中采用熱敏電阻對烤箱的溫度進行實時精確測量，并將測量出的電壓信號送入9089中進行A/D轉換，從而進行溫度檢測。控制部分采用PID控制算法，控制繼電器的通斷時間，最終實現對烤箱溫度的控制。
 
關鍵字：溫度控制 PID控制  A/D轉換
  
  
Abstract
   Temperature is one of the main changed parameters in the industrial object, such as metallurgy, machinery, food, chemical industry, and various kinds of furnaces, heat treatment furnaces, reactors which are strict with the temperature processing controlling of workpiece, because it can directly affect on the physical and chemical processing such as burning, chemical reaction, ferment, baking, calcimine, distillation, concentration, extrusion, crystallization, and air flowing. As technology advances, the compositions of the temperature controller are also changed.
This article explains a kind of design of temperature control platform whose core is Panasonic PLC. Besides it introduces the design of software and hardware, and shows the hardware schematic and the flow chart of software. In this design, the thermistor is used to measure the temperature in the oven, and then the measured voltage is sent to 9089 to for A/D transformation. So it can be capable to measure the temperature. The controlling part is uses PID algorithm, by the way of controlling the working time of relay, it can realize the temperature controlling of the oven.
 
Keywords：Temperature control   PID control  A/D Conversion