单片机在电阻炉控制系统中的应用

论文编号:JD1124  论文字数:18231,页数:45,附电路原理图，C语言程序

摘 要
  采用单片机进行电阻炉炉温控制,具有电路设计简单、精度高、控制效果好等优点,对提高生产效率、促进科技进步等方面具有重要的现实意义。将MCS-51单片机的硬件与软件相结合，并将PID算法运用其中，具有控制方便、组态简单和灵活性大等优点，可以大幅度提高被控温度的技术指标。基于单片机的电阻炉控制系统是这样一个调节过程：由单片机定时对炉温进行检测，经A/D转换芯片得到相应的数字量和需要的量得到偏差，通过对偏差的处理获得控制信号，调节电阻炉的加热功率，系统采用了较为广泛运用的PID控制算法，把检测温度和温度设定值相比较，通过PID控制算法，计算、调节输入功率，从而达到温度控制的目的。在测定和控制温度的过程中可以通过LED显示器显示温度的变化过程，同时连上报警装置，达到安全，时实控制温度的效果。使得该系统设计合理、功能完善、性能优越。

关键词  电阻炉  PID  温度控制  LED显示器

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

目   录

 1  绪论…………………………………………………………………………………… 1
 1.1  本课题意义………………………………………………………………………… 1
 1.2  国内外发展状况…………………………………………………………………… 2
 2  单片机温度控制系统的硬件设计………………………………………………… 4
 2.1  单片机温度控制系统的工作原理……………………………………………… 4
 2.2  MCS-51单片机……………………………………………………………… 5
 2.3  温度检测元件和变送器……………………………………………………… 8
 2.4  A/D转换电路及其接口技术……………………………………………… 11
 2.5  键盘/显示电路……………………………………………………………… 14
 2.6  温度过零触发保护控制电路………………………………………………… 20
 2.7  报警与指示电路……………………………………………………………… 22
 3  系统的软件设计………………………………………………………………24
 3.1  系统主程序………………………………………………………………… 24
 3.2  温度检测与标度变换子程序……………………………………………… 25
 3.3  PID参数整定方法………………………………………………………… 27
 3.4  数字调节器的设计………………………………………………………… 31
 3.5  数字触发器的设计………………………………………………………… 35
 结论 ………………………………………………………………………………… 37
 致谢 ………………………………………………………………………………… 38
 参考文献………………………………………………………………………………39
 附录…………………………………………………………………………………41
 附录A  硬件原理图………………………………………………………………… 41
 附录B  程序………………………………………………………………………… 42