摘要在工业控制领域,温度测量非常重要,采用K型热电偶对温度进行测量已经十分广泛。本论文主要是对K型热电偶进行调理电路设计,简要介绍了本设计的研究背景,发展状况。主要包括对热电偶测温系统的冷端补偿、放大滤波和线性化部分设计,因为不同设计方法对测量结果的影响不同,所以本论文设计了三种热电偶调理电路,第一种方案是基于AD590和AD538的调理电路设计,第二种是基于电桥和AD538的热电偶调理电路设计,第三种是基于ICL7106的热电偶调理电路设计。文中详细论述了各方案中元器件的选择依据,并绘制原理图和PCB图,同时对设计中的放大和冷端补偿部分进行仿真分析,并根据设计方案搭建实验电路,进行实验调试及数据处理。然后对第二种调理系统进行动态实验,得到此热电偶调理系统的时间常数,幅度谱和相位谱,并对实验结果进行比较和误差分析。60923
最终所设计的热电偶调理系统的测温范围在2.35℃~1300℃之间, 在中高温时测温精度较高,时间常数为5.12S,静态灵敏度为9.838mV/℃,是完全的硬件电路,体积小,成本低,应用方便,是比较合适的小型化调理电路,有一定的实用价值。
毕业论文关键词 K型热电偶 冷端补偿 放大滤波 线性化
毕业设计说明书(论文)外文摘要
Title Conditioning Circuit Design of K-type Thermocouple
Abstract In the area of industrial control,temperature measurement is very important,and the K-type thermocouple is widely applied in measuring temperature. This thesis is a K-type thermocouple conditioning circuit design, briefly introducing the research background, and the development. It includes thermocouple cold junction compensation, amplification, filtering and linear portions. Because of the different methods have a different impact on the measurement results, therefore, designing three different conditioning circuit, the first scenario is based on the AD590 and AD538,the second is based on the bridge and the the AD538, and the last one is based on ICl7106. This thesis discusses the electing basis for components in details.Designing the schematic and PCB diagramand,then imulating the amplification circuit and cold junction compensation(CJC) circuit , building the experimental circuit according to the design scheme , debugging circuit and processing and anlyzing experimental data. Then conducting a dynamic experiment to the time constant, amplitude spectrum and phase spectrum of the system , and comparing the experimental and doing error analysis. The ultimate design of temperature measuring range is 2.35℃~1300℃. It has high precision in medium-hign temperature measurement, the time constant is 5.12s, and the static sensitivity is 9.838mv/c. It's a pure hardware circuit with small size, low cost and convenievt application. It's a comparatively appropriate miniaturized circuit, and has certain practical value.
Keywords K-type thermocouple cold junction compensation amplified and filtered linearization
1 绪论 1
1.1 研究背景 1
1.2.1 K型热电偶冷端补偿技术 2
1.2.2 热电偶调理方法介绍 3
2 K型热电偶简介 5
2.1 K型热电偶测量原理 5
2.2 K型热电偶特点 6
2.3 本章小结 7
3 K型热电偶调理电路总体方案设计