智能热电偶测温系统设计

智能热电偶测温系统设

计

摘要

温度是表征物体冷热程度的物理量。在工农业生产和日常生活中，对温度的测量控制始终占据着重要地位。温度传感器应用范围之广、使用数量之大，也高居各类传感器之首。

本文使用温度传感器设计了一个完整的测温系统。该系统所采用的温度传感器为热电偶，A/D转换器件为ADC0809，微型计算机采用的是MCS-51单片机。系统将温度变换、显示和控制集成于一体，用软件实现系统升、降温的调节，控制采用了模糊控制原理对系统进行控制。

设计的系统所满足的技术指标：测温范围为500—800℃，响应时间为小于等于1s，误差范围为-5℃—+5℃。

关键词：热电偶 A/D转换模糊控制

ABSTRACT

Temperature is the physical quantity of symptom object cold hot level. In the daily life and production of industry and agriculture, occupy important position all along for the measure control of temperature. Temperature sensor application broad scope and use big quantity, also hold the head of each kind of sensor high.

This paper uses temperature sensor and has designed , is a and complete to measure warm system. The temperature sensor adopted by this system is thermocouple, the converter of A/D is ADC0809, what personal computer adopt is that MCS-51 only flat machine. System alternates temperature , shows and controls to be more integrated than one body , realizes system with software to rise , cool down regulation, control has adopted vague control principle as system controls.

The technical index of design satisfied by system: Measure warm scope is 500 —800 ℃, respond time to be smaller than is equal to 1 s, scope is error - 5℃— + 5℃.

Keyword: Thermocouple Conversion of A/D Vague to control

目录

第一章绪论.................................................................................................. - 1 -第二章系统设计.......................................................................................... - 2 -第三章硬件结构及分析.............................................................................. - 4 -

3.1温度检测元件—热电偶 (4)

3.1.1热电偶的特性.................................................................................................... - 4 -

3.1.2热电偶的基本定律............................................................................................ - 6 -

3.1.3热电偶测温........................................................................................................ - 6 -3.2电源电路.. (9)

3.3测量电路 (10)

3.4滤波电路 (11)

3.5控制电路 (12)

3.6A/D采集部分原理 (13)

3.6.1 A/D转换器概述.............................................................................................. - 13 -

3.6.2逐次逼近式A/D转换原理 ............................................................................. - 13 -3.7显示部分原理. (15)

3.8键盘部分的应用 (16)

3.8.1键盘的工作原理.............................................................................................. - 16 -

3.8.2矩阵式按键接口.............................................................................................. - 17 -

3.8.3键盘、显示器组合接口................................................................................. - 19 -第四章控制软件及流程............................................................................. - 22 -4.1键盘、显示及A/D转换 (22)

4.2控制程序 (24)

4.2.1控制程序原理................................................................................................ - 25 -

4.2.2模糊控制在该系统中的实现.......................................................................... - 26 -