单片机水温控制系统

电子机电论文编号:JD279     论文字数:14574,页数:47  

 目    录
概   述 1
绪  论 4
1  硬件部分 5
1.1 测温电路的设计 5
1.1.1 温度传感器AD590简介 5
1.1.2 放大滤波电路的设计 7
1.1.3晶闸管主电路及驱动电路的设计 9
1.2单片机控制部分的设计 13
1.2.1  MCS-51单片机的选择 13
1.2.2 键盘及显示电路 14
1.2.3 8255并行接口 17
1.2.4 DA转换DAC0832与AD转换ADC0809 18
1.3 单片机温度控制系统的设计 21
1.3.1 光电隔离 21
1.3.2 固态继电器 23
1.3.3 看门狗及复位电路 23
1.3.4单片机温度控制系统总体布局图 24
2 软件部分 25
2.1  PID 控制算法 25
2.2 A/D转换程序 28
2.3数字滤波子程序FILTER 29
2.4二进制转十进制子程序BCDCH 31
2.5 8255并行口子程序设计 32
2.7数据显示及打印设计 34
2.7 温度控制程序,流程图 34
3结论与讨论  42
3.1结论 42
3.2本系统存在的不足 42
致谢 43
参考文献 44

摘 要
本文介绍了利用单片机进行水温测量和控制的智能化的方法。对MCS-51单片机及其扩展系统的原理及结构进行了详尽论述。测温系统温度传感器AD590，信号放大部分采用两级运放电路及二阶压控LPF。两部分电路制作在一块PCB板上，并封装在一屏蔽金属盒内，经调试性能很好。本系统借助于传感器、A/D, D/A转换器、扩展的并行接口以及执行机构进行的。在闭环过程控制中，过程的实时参数由传感器和A/D转换器实时采集，并由微型计算机自动记录、统计制表，然后再通过D/A转换器或并行接口输出控制信号，控制执行机构动作，进行调节和控制。
另外本系统还扩展了另外一个温度传感器及相关电路，利用它进行室温采集，并通过8255并行口扩展LED显示，这样能更清楚的看到当周围温度发生变化时水温的变化。
还详尽讨论了这部分电路与8051单片机系统的硬件接口问题。本文采用PID控制算法作为温度控制算法，采用固态继电器和单结管弛张振荡电路作为其执行驱动机构，达到了较高控温精度。
 

关键词:  8051单片机  温度测控   传感器   PID算法
固态继电器

ABSTRACT
The introduction to this text utilizes the single computer to carry on temperature measurement and control intelligent method . And expanded systematic principle and structure and describe to MCS-51 one-chip computer exhaustivly. Examining warm system temperature sensor AD590, the signal amplifies and adopts and transports and puts circuit and two stepses of voltage-controlled LPF three times accurately partly. Two parts of circuit are made on a PCB board, and seal the form in a shielding metal box , it is very good through debugging performance . System this with the aid of sensor, A/D, D/A converter, expand that the interface and executive body go on. In the course of the ring closing type is controlled, real-time parameter of course gather in real time by sensor and A/D converter, and by the automatic record of the microcomputer, count the tabulation, then or the interface runs side by side to export the control signal through D/A converter , control movements of executive body, regulate and control.
This system has also expanded another temperature sensor and relevant circuit in addition, utilize it to carry on the room temperature to gather , and the mouth runs side by side to expand LED and show , can see the change of the temperature when change in environment temperature clearer in this way through 8255.
Have also discussed the hardware interface questions of this part of circuit and 8051 one-chip computer systems exhaustivly. This literary grace controls algorithms as the temperature control algorithm with PID, adopt the solid state relay and form and in charge of the relaxation one to shake circuit and carry out and drive the organization as it only, have reached the higher precision of controlling the temperature.

Keyword: stional Integral Differential arithmetic;Solid electronic peeker;8051 single chip computer;Temperature detecting and controlling;