摘要本文主要介绍了基于热电偶温度传感器的快速测温系统的设计。本文综合考虑到热电偶的热惰性时间常数问题，采用快速算法实现了温度快速测量的功能。快速算法思想是：在等时间间隔内快速采集三个温度数据，然后根据它们与热时间常数、初始温度以及稳定后的温度之间的关系，最后得出稳定后温度的数学计算公式，从而得到所测量的温度值。
本论文采用了带有冷端补偿的温度转换芯片MAX6675、K型热电偶、89C51单片机、数码管等元器件设计了相应温度采集电路、温度转换电路、温度控制电路、超量程报警电路、数码管显示电路。结合硬件电路给出了相应的软件设计，测温精度可达到0.25℃。本系统的工作流程是：首先热电偶采集温度，数据经过MAX6675内部电路的处理后送给单片机进行算法处理，最后通过数码管电路显示出测量温度。本设计最后对系统进行了protuse的调试和仿真，实现了设计的要求。10338
关键词 温度传感器 热电偶 热时间常数 冷端补偿
毕业设计说明书（论文）外文摘要
Title BASED ON THERMOCOULPLE TEMPERATURE SENSOR TEMPERATURE MEASURING SYSTEM DESIAHN
Abstract
This design describes the thermocouple temperature sensor based on the rapid temperature measurement system. This comprehensive taking into account the thermal inertia of the thermocouple time constant problem, the use of fast algorithm features fast measurement of temperature. Fast algorithm idea is: in the other three intervals quickly acquire temperature data, and then based on they contact with thermal time constant, initial temperature and stable temperature, Finally, temperature formula is given, so we can obtain the measured temperature values.
This design uses a temperature conversion chip MAX6675，K-type thermocouple, 89C51microcontroller, LED and other components, design corresponding temperature acquisition circuit, temperature converter circuit, temperature control circuit, over-range alarm circuit, the LED display circuit. With the hardware give out The corresponding software design, temperature measurement accuracy up to 0.25 ℃．The system works is: first acquisition thermocouple temperature data through the Treatment of the of the MAX6675 internal circuit and be then sent to 89C51 Aim for rapid algorithm processing. Finally, the LED circuit shows the measurement temperature values. In the last, the design of the system was protuse debugging and simulation,achiev the design requirements.
KEY WORDS Temperature sensor Thermocouple Thermal time constant Cold
junction compensation
目 次
1 绪论 1
2 系统原理概述 3
2.1 快速测温的算法实现 3
2.2 热电偶测温基本原理 5
2.3 热电偶冷端补偿方案确定 5
2.3.1 分立元气件冷端补偿方案 5
2.3.2 集成电路温度补偿方案 6
2.3.3 方案确定 6
2.4 硬件组成原理 7
2.5 软件系统工作流程 7
3 硬件设计 9
3.1 热电偶简介 9
3.1.1 热电效应 9
3.1.2 热电偶基本定律 10
3.1.3 热电偶温度补偿 11
3.1.4 热电偶的结构形式 12
3.1.5 K型热电偶概述 13
3.1.6 K型热电偶特点 14
3.2 具有冷端补偿的数字温度转换芯片MAX6675功能简介 15
3.2.1 冷端补偿专用芯片MAX6675性能特点 15
3.2.2 冷端补偿专用芯片MAX6675温度变换 16 89C51单片机热电偶的温度测量系统设计:http://www.youerw.com/tongxin/lunwen_9356.html