單片機在電阻爐控制系統中的應用

電子論文編號:JD1124  論文字數:18231,頁數:45,附電路原理圖，C語言程序
目   錄

 1  緒論…………………………………………………………………………………… 1
 1.1  本課題意義………………………………………………………………………… 1
 1.2  國內外發展狀況…………………………………………………………………… 2
 2  單片機溫度控制系統的硬件設計………………………………………………… 4
 2.1  單片機溫度控制系統的工作原理……………………………………………… 4
 2.2  MCS-51單片機……………………………………………………………… 5
 2.3  溫度檢測元件和變送器……………………………………………………… 8
 2.4  A/D轉換電路及其接口技術……………………………………………… 11
 2.5  鍵盤/顯示電路……………………………………………………………… 14
 2.6  溫度過零觸發保護控制電路………………………………………………… 20
 2.7  報警與指示電路……………………………………………………………… 22
 3  系統的軟件設計………………………………………………………………24
 3.1  系統主程序………………………………………………………………… 24
 3.2  溫度檢測與標度變換子程序……………………………………………… 25
 3.3  PID參數整定方法………………………………………………………… 27
 3.4  數字調節器的設計………………………………………………………… 31
 3.5  數字觸發器的設計………………………………………………………… 35
 結論 ………………………………………………………………………………… 37
 致謝 ………………………………………………………………………………… 38
 參考文獻………………………………………………………………………………39
 附錄…………………………………………………………………………………41
 附錄A  硬件原理圖………………………………………………………………… 41
 附錄B  程序………………………………………………………………………… 42

摘 要
  采用單片機進行電阻爐爐溫控制,具有電路設計簡單、精度高、控制效果好等優點,對提高生產效率、促進科技進步等方面具有重要的現實意義。將MCS-51單片機的硬件與軟件相結合，并將PID算法運用其中，具有控制方便、組態簡單和靈活性大等優點，可以大幅度提高被控溫度的技術指標。基于單片機的電阻爐控制系統是這樣一個調節過程：由單片機定時對爐溫進行檢測，經A/D轉換芯片得到相應的數字量和需要的量得到偏差，通過對偏差的處理獲得控制信號，調節電阻爐的加熱功率，系統采用了較為廣泛運用的PID控制算法，把檢測溫度和溫度設定值相比較，通過PID控制算法，計算、調節輸入功率，從而達到溫度控制的目的。在測定和控制溫度的過程中可以通過LED顯示器顯示溫度的變化過程，同時連上報警裝置，達到安全，時實控制溫度的效果。使得該系統設計合理、功能完善、性能優越。

關鍵詞  電阻爐  PID  溫度控制  LED顯示器

Abstract
A monolithic integrated circuits for resistance of the furnace control the temperature, precision and effective control of the advantages and to improve the efficiency of production and promoting scientific and technological progress and possess important actual significance. will MCS-51 monolithic integrated circuits of the hardware and software combined, and PID algorithms use of it, has control convenient, the configuration is simple and advantage that the flexibility is great, and can improve the technical indicator which is accused of temperature by a large margin. Revivification of resistance of the furnace control system is such an adjustment process: Monolithic integrated circuits to warm up by the testing, change by A/D chip get the corresponding figures to quantity and need to get the deviation, to offset by the handling of a control signal, the stove heats the power of resistance, System adopted more widely used PID control algorithm, put to test the temperature and set value temperature is compared，with PID control algorithm，calculate，adjust the input power，to achieve the purpose of the control the temperature. In the determination and control the temperature of the process LED by the display the temperature change process, at the same time, even on the device, reach the safe, when a firm control of temperature effect. The system design reasonable, perfect in shape and function and superior performance.

Key Words  resistance furnace  PID  temperature control  LED display