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哈尔滨理工大学学士学位论文-I-哈尔滨理工大学毕业设计题目：基于热电偶的控温器设计院系：电气与电子工程学院姓名：王亮指导教师：孙崐系主任：刘泊2013年6月21日哈尔滨理工大学学士学位论文-II-基于热电偶的控温器设计摘要热电偶（thermocouple）是温度测量仪表中常用的测温元件，它直接测量温度，并把温度信号转换成热电动势信号。各种热电偶的外形常因需要而极不相同，但是它们的基本结构却大致相同，通常由热电极、绝缘套保护管和接线盒等主要部分组成。本文研究开发的抗干扰热电偶控温器，从电路设计、PCB电路板布局布线、到软件设计等方面，对热电偶工作的干扰信号进行滤波处理，使这一热电偶控温器能够在复杂的电磁环境下稳定、可靠地工作。为了达到提高测温精度的目的，需要对热电偶进行冷端补偿，以弥补热电偶冷端处于室温环境时造成的误差；在PCB电路设计中，从电源、电缆、印制板三个层次对热电偶控温器进行抗干扰设计；在软件设计过程中，利用数字滤波技术进一步对干扰信号滤波处理、并用线性插值法求解温度值，最后用模糊算法实现控温器对环境温度的控制。关键词热电偶；冷端补偿；控温器；抗干扰哈尔滨理工大学学士学位论文-III-ADesignofThermocoupleBasedTemperatureControllerAbstractThermocouple(thermocouple)isacommonlyusedtemperaturesensortemperaturemeasurementinstrument,Itmeasurethetemperaturedirectly,andthetemperaturesignalisconvertedintothethermalelectromotiveforceone.Theshapeofthethermocoupleisnotthesamebecausethedifferentneeds.buttheirbasicstructureareroughlythesame,andusuallycomposeofahotelectrode,insulatingsleevetubeprotectorandthejunctionboxandothermainparts.Thisresearchisabouttheresearchofananti-disturbedtemperaturecontrollerwiththermocoupleasitsthermalsensor.Inordertomakethetemperaturecontrollerworkstablyandreliablyinacomplicatedelectromagneticenvironment,differentmethodsareusedinthedesignstage.Thesemethodscoverdifferentstagesofthedesign,includingthedesignofthehardwarecircuit,thelayoutoftheprintedcircuitboard(PCB),andthesoftwaredesign.Inthedesignofthehardwarecircuit,inordertoimprovetheaccuracyofthetemperaturecontroller,it’snecessarytodosomeworkonthecoldjunctioncompensation.Becausethethermocoupleisusuallyworkwithitscoldjunctionintheroomtemperatureratherthaninthestandardof0℃.InthePCBdesignstage,threedesignhierarchiesareusedtomakethetemperaturecontrollerimmunetothedisturbanceoftheelectromagneticenvironment,thesehierarchiesinclude:powersupply,electriccable,andtheprintedcircuitboard.Inthesoftwaredesign,thedigitalfilterisusedtofinallyfilterthedisturbsignal,andtheFuzzyalgorithmicapproachisusedtorealizethethermalcontrol.KeywordsThermocouple;Coldjunctioncompensation;Temperaturecontroller;Anti-disturb哈尔滨理工大学学士学位论文-IV-目录摘要....................................................................................................................IAbstract................................................................................................................II第1章绪论........................................................................................................11.1课题背景...................................................................................................11.2国内外发展现状.......................................................................................11.3本设计技术指标.......................................................................................31.4本文主要研究内容...................................................................................3第2章热电偶测量温度原理............................................................................52.1热电偶传感器分类...................................................................................52.2热电偶的选取...........................................................................................62.3热电效应与热电势...................................................................................62.4热电偶测温基本原理...............................................................................72.5热电偶的冷端补偿...................................................................................72.6本章小结...................................................................................................8第3章热电偶温度控制系统的硬件设计........................................................93.1控温器系统结构.......................................................................................93.2系统的信号选通及A/D转换电路..........................................................93.3单片机.....................................................................................................123.4串行数据通信.........................................................................................143.5温度控制电路.........................................................................................183.6本章小结.................................................................................................23第4章热电偶温度控制系统的软件设计......................................................244.1软件总体方案设计.................................................................................244.2查表法和插值法相结合求解温度值.....................................................264.3数字滤波.................................................................................................264.4模糊控制算法.........................................................................................274.5本章小结.................................................................................................28结论....................................................................................................................30致谢....................................................................................................................31参考文献............................................................................................