project_I-III温度检测系统_A
(推荐 多系统)DCS班题库汇总_
理论考试试题一、填空题1、我厂FOXBORO系统用的冗余的AO卡是：FBM2372、TRICON控制器是一种：三重化冗余容错控制器3、污水工段，雨水收集工段，循环水工段用的是浙大中控(supcon)的jx-300xp 系统4、本厂报警仪分为可燃气体报警仪和有毒气体报警仪，其中可燃气体测的气体有CH3OH、H2，有毒气体报警仪测的气体有CO、H2S、NH4 。
二、判断题1、PL C简称可编程控制器（√）2、MTL5074安全栅是测量温度点的安全栅（√）3、热电阻B和C线中有一根接触不良，对仪表指示无影响。
（╳）4、同等情况下多模光纤要比单模光纤传输距离远（×）三、选择题1、下面哪个符号代表调节阀。
（A）A）FV B）FT C）FY D）FE2、DCS系统的接地分为（B）种A. 4B.3C. 1D.23、二期空分霍尼韦尔PKS系统，他的控制器名称为（A ）A C300B C200C C100D C4004、网络传输介质分为有线传输介质和无线传输介质，以下有线介质不包括（A ）A 红外线波 B 电缆 C 双绞线 D 光纤四、简答题：1、一期空分工段使用的霍尼韦尔的什么系统？安全保护使用的是康吉身（CONSEN）的什么系统？答：一期空分工段使用的霍尼韦尔的PKS系统安全保护使用的是康吉身（CONSEN）的trident系统2、ESD、SIS 、ITCC的中文简称分别是什么?答：ESD的中文简称是紧急停车系统SIS简称安全仪表系统ITCC 简称透平综合控制系统3、中控室用的模拟量输入安全栅都有哪些（至少三种）？答：MTL5041 MTL5042 MTL50434、FOXBORO 用到的卡件都有哪些？（至少三种）答：FBM217 FBM237 FBM242 FBM211五、问答题;1、ICC312信号隔离器的作用？答;ICC312信号隔离器用于4-20MA 2线制变送器或者电流源，ICC312是用于2线制变送器的全隔离的隔离器，并将现场的信号转换为两路4-20MA的电流源输出2、卡件XP367的FAIL RUN WORK COM POWER 灯代表什么意思？答;FAIL灯卡件故障指示RUN灯卡件运行指示WORK工作/备用指示COM数据通讯指示POWER 电源指示3、计算机网络拓扑结构可以分为哪几类？答：总线型拓扑结构，环形拓扑结构，星形拓扑结构，树型拓扑结构，网状型拓扑结构4、循环水8通道DI卡件XP363 CH1/CH2灯亮红色，绿色，和闪烁各代表什么意思? 答：CH1/CH2 灯亮红色：代表第二通道有信号进入DCS卡件；CH1/CH2灯亮绿色：代表第一通道有信号从现场进入DCS卡件，CH1/CH2灯闪烁：代表第一通道和第二通道同时有信号从现场进入到DCS卡件一．填空题1.如果调节时需要修改给定值，那么回路的操作方式应为自动模式。
基于单片机的电阻炉温度控制系统设计37
术
创
新
图 ３ 键盘、时钟、报警和控温电路 ３．３ 键盘显示和报警电路 本 系 统 采 用 ３＊３ 键 盘，由 单 片 机 Ｉ／Ｏ 口 控 制，可 通 过 按 键 设 定 温 度 和 时 间 ，有 的 按 键 在 不 同 情 况 下 可 以 实 现 不 同 功 能 。显 示 器 选 用 点 阵 字 符 型 液 晶 显 示 器 ＴＣ１６０２， 系 统 中 将 扩 展 芯 片 ８１５５ 的 Ｐ０ 口 、ＰＣ．０～ＰＣ．２ 口 与 ＴＣ１６０２ 接 口 相 连 ，ＴＣ１６０２ 的 显 示形式是 １６＊２ 行，可显示炉温、设定时间、实际时间 等 。报 警电 路 是 将单 片 机 的 Ｉ／Ｏ 口 与 驱 动 芯 片 ＭＣ１４１３ 相 连，通 过 ＭＣ１４１３ 驱动蜂鸣器。键盘电路和时钟电路如图 ３ 中所示。 ３．４ 控温电路 控温电 路包 括 驱 动芯 片 ＭＣ１４１３、过 零型 交 流 固态 继 电 器 （Ｚ 型 ＳＳＲ）。报警和控温电路如图 ３ 中所示。 Ｚ 型 ＳＳＲ 内 部 含有 过 零 检测 电 路，当加 入 控 制 信 号，且 负 载 电源电压 过 零 时，ＳＳＲ 才 能 导 通；而 控 制 信号 断 开 后，ＳＳＲ 在 交 流 电正 负 半 周交 界 点 处断 开 。也 就是 说，当 Ｚ 型 ＳＳＲ 在 １ 秒 内 为 全导通状态时，其被触发频率为 １００ＨＺ；当 Ｚ 型 ＳＳＲ 在 １ 秒 内 导 通时间为 ０．５ 秒时， 其被触发频率为 ５０ＨＺ。在本 系 统中， 采 用 ＰＩＤ 控制算法， 通过改变 Ｚ 型 ＳＳＲ 在单位时间 内 的 导通 时 间 达 到 改 变 电 阻 炉 的 加 热 功 率 、调 节 炉 内 温 度 的 目 的 。
SWAN客户端安装和使用手册
SWAN客户端安装和使用手册12020年5月29日短临客户端用户手册1、系统结构短临业务系统采用客户端/服务器结构,所有数据处理、报警数据、算法产品、检验产品的生成和存储均在服务器上进行,服务器上有调度程序有计划地运行各数据模块。
服务器调度程序一旦检测到有新的产品数据或报警数据生成,将即刻经过网络模块以网络消息的方式在局域网内进行广播,凡是安装了短临客户端软件的计算机都能够经过网络接收模块接收服务器广播的消息。
客户端判断接收到的服务器消息类型,并根据消息的类型进行数据的显示、报警、闪烁等处理。
系统软件包括数据服务器调度软件和客户端软件。
1.1 服务器数据源雷达组网的雷达基数据、雷达产品数据、自动气象站数据、加密气象站数据、雨量站数据、重要天气报等。
1.2 服务器产品类型（1）实况数据:实况雨量数据(包括1小时雨量、3小时雨量、6小时雨量、12小时雨量);实况温度数据(包括1小时最高气温、小时最低温度、当日最高气温、当日最低温度、高温连续日数、24小时低温降幅、48小时低温降幅);大风数据22020年5月29日(包括极大风、平均最大风、十七秒米开始时间、十七秒米结束时间);冰雹;龙卷;电线积冰;雾;沙尘暴;积雪;（2）雷达数据及拼图产品:雷达反射率三维拼图、组合反射率(基数据)、液态水含量(基数据) 、回波顶高(基数据) ;雷达产品(pup常见产品);雷达基数据;（3）雷达特征量数据:风暴ID号、风暴所在地点、方位、距离、风暴所在经度、风暴所在纬度、顶高、1.5度仰角反射率、最大反射率、底高、风暴中心高度、风暴移动速度、风暴移动方位、强冰雹概率、一般冰雹概率、冰雹尺寸、中气璇底高、顶高、中心高度、切向直径、径向直径、切变值、风暴类型等;（4）算法产品:TREC矢量场、1小时降水预报、1小时降水估测、STM风暴识别追踪预报产品、TITAN风暴识别算法产品、反射率预报;冰雹、龙卷的识别算法产品;（5）报警数据:雷达报警、强阵雨、暴雨、强风、冰雹、龙卷、寒潮、高温、电线积冰、雾、沙尘暴、积雪;（6）算法检验产品:反射率预报检验、1小时降水预报检验、STM检验;（7）MIF格式地理信息数据、SHP格式地理信息数据;1.3 客户端功能32020年5月29日SWAN客户端软件用以接收服务器发送的消息,并显示服务器上的各种产品数据和报警数据,对于报警数据客户端同时会发出声音报警并辅图形闪烁。
基于热电偶的测温系统设计 毕业设计完整版
XXXX毕 业 设 计设计题目：基于热电偶的测温系统设计系 别：_________________________班 级：_________________________姓 名：_________________________指 导 教 师：_________________________2014年6月11 日Xx XXX 测控技术与仪器1班 机电工程系基于热电偶的测温系统设计摘要在工业生产过程控制中，温度是一个重要的测量参数，而热电偶是工程上应用最广泛的温度传感器之一，他的主要特点就是测温范围宽，性能比较稳定，同时同时结构简单，动态响应好，更能够远传4-20mA电信号，便于自动控制和集中控制，在温度测量中占有重要地位。
但由于热电偶的热电势与温度成非线性关系增加了显示与处理的复杂性；且随着工业发展、自动化的不断加强，对温度精度要求越来越高。
在现代化的工业现场，常用热电偶测试高温，测试结果送至主控机。
由于热电偶的热电势与温度呈非线性关系，所以必须对热电偶进行线性化处理以保持测试精度。
该系统以单片机为控制核心，通过高精度模/数转换器对热电偶电动势进行采样、放大，并在单片机内采用一定算法实现对热电偶的线性化处理并通过液晶屏显示相应测量数据。
关键词：传感器热电偶模/数转换器液晶屏The design of temperature measurement system based on thermocoupleAbstractIn the industrial production process control, the temperature is an important survey parameter, but the thermo-element is in the project applies one of most widespread temperature sensors, his main characteristic is the temperature measurement scope is wide, the performance quite is stable, simultaneously the structure is simultaneously simple, the tendency responds, can pass on the 4-20mA electrical signal far, is advantageous for the automatic control and the common control, holds the important status in the temperature survey. But because the thermo-element thermoelectric force and the temperature became the non-linear relations to increase the demonstration and the processing complexity; Also along with the industrial development,the automated unceasing enhancement, is more and more high to the temperature precision request. Thermocouple is used frequently in high-temperature test in the modernized industry scene, then the test results are deliver edto master control machine. As the non-linear relationship between thermoelectric potential and temperature, it must be carried out on the thermocouple linear processing in order to maintain accuracy of test. It employs SCM as a core of controlling. This article is for the linearization of thermocouple. The general idea is to study high-precision A/D converter,which samples and enlarges the thermoelectric potential from the thermocouple, the measurement data is displayed by LCD screenKeywords：sensor thermocouple A/D converter LCD screen1引言1.1设计背景和思路随着电子信息技术、新材料及自动化技术的发展，传感器技术也得到了日新月异的发展，单片机和自动控制系统在统诸多领域得到了极为广泛的应用。
高精度测温系统多通道模拟开关等效内阻温度标定补偿方法
高精度测温系统多通道模拟开关等效内阻温度标定补偿方法周成;江明明;吴文启;于化鹏;孔祥龙【摘要】The measurement precision of temperature measuring system used in the field would be degraded highly, because the internal resistance of analog switch and other elements would vary big affected by environmental temperature. To solve this problem , the experimental project to calibrate the internal resistance of analog switch and other elements in every channel based on the existent hardware has been researched. A Savitzky-Golay Filter is designed to deal with the noise in the experimental data. Using the least square estimation method,the equivalent internal resistance characteristics of every channel varied with temperature has been obtained. Consequently the measurement precision of temperature measuring system can be improved greatly after the real time compensation to measurement output. Results of sufficient experiments show that the temperature measurement precision of the system designed is better than 0. 03℃ in all environment temperature when temperature changing slowly or acutely.%用于野外环境的测温系统由于内部模拟开关及元器件内阻等受环境温度的影响会发生较大变化,测温精度大大降低.针对这一问题,在现有硬件系统的基础上研究了测温系统各通道模拟开关及元器件内阻标定的实验方案,设计了Savitzky-Golay滤波器对实验数据中的噪声进行处理,并通过最小二乘法拟合出各通道等效内阻的温度变化特性,从而对系统测量输出进行实时补偿,使系统的测温精度得到大幅提高.大量的实验表明,在全温度范围内温度缓变和剧变时,测温精度均优于0.03℃以内.【期刊名称】《仪表技术与传感器》【年(卷),期】2012(000)012【总页数】4页(P92-94,115)【关键词】多通道;测温;Savitzky-Golay滤波器;标定;温度补偿【作者】周成;江明明;吴文启;于化鹏;孔祥龙【作者单位】国防科学技术大学机电工程与自动化学院,湖南长沙410073;国防科学技术大学机电工程与自动化学院,湖南长沙410073;国防科学技术大学机电工程与自动化学院,湖南长沙410073;国防科学技术大学机电工程与自动化学院,湖南长沙410073;国防科学技术大学机电工程与自动化学院,湖南长沙410073【正文语种】中文【中图分类】TB9420 引言随着科技的发展和进步，温度测量系统已被广泛应用于工农业生产、科学研究和日常生活等领域，武器型号、重大装备及精密制造技术等对温度测量精度的要求也越来越高［1］。
18B20 温度采集系统硬件电路(二)方案设计
SetOutput()设置缓冲区输出数据等。
MSComm 使用时主要注意的就是数据形式的变换，代码如下：
VARIANT variant_inp = m_ctrlComm.GetInput(); //读缓冲区
COleSafeArray safearray_inp = variant_inp;
//VARIANT 型 变 量 转 换 为
位置，layer 为显示的层,width 为要显示的宽度
void Init_DS18B20(void)；
//18B20 初始化
uchar ReadOneChar(void)；
//从 18B20 读一个字节
void WriteOneChar(unsigned char dat)； //向 18B20 写一个字节
的形式，列表框适合表示实时温度，曲线图适合观察长期的温度变化和温度变化范围。 （ 2 ） 默 认 使 用 COM1 、 19200bps 波 特 率 ， 可 以 进 行 设 定 ， 串 口 可 选 择
COM1/COM2/COM3，波特率可以选择 4800bps/9600bps/19200bps/38400bps。 （3）可以设定温度采集时间间隔，单位是 S，最小值是 1。（定时使用的是 SetTimer
三、上位机软件 上位机软件使用 .0 编写： 1、由于需要做出温度曲线，采用 Window API 画图较为繁琐且不易控制，这里采用专
业的图表控件 TeeChart Pro ActiveX 8.0 试用版： TeeChart Pro 是西班牙 Steema Software 公司开发的图表图形控件，它适用于 VB、
-1-
（三）实习报告
一、实现的功能： 1、下位机程序 （1）在没有连接上位机软件的时候，可以按通讯键来采集温度并用液晶显示出来，
DCS系统规格书
提供配备有打印机和进行应用软件编制的工程师站。
(3) 辅助操作台和机柜
供货商提供其标准机柜用于安装所有的 DCS 设备，如控制器，I/O 模块等。
其它辅助机柜应与 DCS 柜在结构上相同。
应提供下列辅助操作台和机柜
带信号报警器和手动开关的紧急停车操作台
安装在现场机柜间操作室内操作台数如下：DCS 操作台 2 个， PDS 操作台 1 个，
BN 柜
色谱分析仪
冷冻系统
(4) 安全栅
在危险区为 1 级 1 类和 1 级 2 类区域使用的设备类型应满足如下要求：
变送器，转换器
本安型
DPEC 持有国家甲级工程设计证书：A123003976; 本文件未经 DPEC 许可不得向第三方扩散。
S4991.01-ZK06-01
0
11ZMMD01–3000–ZK–TEN–0052
规格书要求的整套硬件和软件。
规定的所有附件（成套提供的各类机柜和操作台）。
所有电缆如系统电缆，通讯电缆，预制的内部电缆等等。
与其它系统（计算机，PLC 等等）的通讯接口。
具有单价的两年操作用备件（作为一个选项）。
三个月试车用消耗品。
专用工具（如果需要）
文件和图纸
DPEC 持有国家甲级工程设计证书：A123003976; 本文件未经 DPEC 许可不得向第三方扩散。
作台 1 个，造粒操作台 2 个， 添加剂操作台 1 个，风送操作站 2 个，GDS 操作台
1 个，SIS 辅操台 1 个，消防操作台 1 个，打印机操作台 1 个，备 1 个，共计 18
个。
安装在中控室工程师室操作台数如下：DCS 操作台 1 个，SIS 操作台 1 个， APC 操
力学试验机温度控制系统设计
力学试验机温度控制系统设计摘要力学试验机现在已经广泛应用在各个机械工厂行业中，对各个工厂的高温合金产品试样进行高温力学拉伸实验，从而能检验其产品的物理力学质量性能，使其能安全有效的投入到生产中去，以前高温力学拉伸实验都是由技术工人凭借经验进行人工操作，进行基于常规仪表的手动控制，控制效率非常低，而且由于炉数较多其控制精度也很低，影响了高温力学拉伸实验的控制效果，从而影响了对产品预估的质量。
所以应采用PID控制算法对试验机进行炉温的自动控制。
在力学试验机温度控制系统设计中力学试验机温度控制主要是控制电阻加热炉的温度，对于这个控制系统常规的PID控制就能达到控制效果，且具有一定得干扰能力，其控制效果比较理想，因此在这个温度系统设计中采用的是PID自适应控制，同时还用计算机与数据采集ADAM模块进行对炉温的自动控制与数据管理，最后利用Visual Basic6．0语言设计一些主控程序和若干子程序模块和一些模型图案来达到最终的设计标。
这个控制系统的使用不仅大大减轻了工人的劳动强度，同时还提高了产品的生产效率。
也使力学试验机温度控制系统设计中充分利用了计算机监控系统的功能与优势，该系统现已应用在全国各个股份有限公司力学试验室中，控制效果良好，对钢厂合金产品的高温拉伸试验起到了很好的控制效果，为企业创造了可观的经济效益。
关键词：力学试验机，PID控制，Visual Basic6．0，ADAM模块Mechanics Experiment Furnace Temperature ControlSystem DesignAbstractMechanics experiment furnace have already widely applied in each Machine shop profession now , it carries on the high temperature mechanics stretch experiment to each factory's heat-resisting alloy product test specimen, thus can examine its product the physical mechanics quality performance, it enables its safe effective investment to the production , The beforehand high temperature mechanics stretch experiment is relies on the experience by the technical worker to carry on the manual control, carries on based on the conventional measuring appliance's hand control, the control efficiency is low, moreover, because the stove number are many its control precision to be also very low, has affected the high temperature mechanics stretch experiment's control effect, thus has affected to the product estimate quality. Therefore it should use the PID control algorithm to try the prototype to carry on the furnace temperature the automatic control.Mechanics experiment furnace temperature control mainly controls the resistance heating furnace's temperature in mechanics experiment furnace temperature control system design, to the control system of conventional PID control ,it can achieve control effect, and has a certain disturbance ability,its control effect is quite ideal, and therefore uses system design in this temperature is the advanced PID adaptive control, Simultaneously also uses the computer and the data acquisition ADAM module carries on to the furnace temperature automatic control and the data management, finally makeuse of the Visual Basic6.0. language to design some master control programs and certain subroutine module and some model design to achieve the final project objective.This control system's use not only greatly reduced worker's labor intensity, meanwhile raised the product production efficiency. Simultaneously in mechanics experiment furnace temperature control system design has used the computer supervisory system's function and the superiority fully, this system already applied in the nation each Limited liability company mechanics test chamber, the control effect is good, to the steel mill alloy product's high temperature pulling test very good control effect, has created the considerable economic efficiency for the enterprise.Key words: Mechanics experiment furnace; PID control; Visual Basic6.0; ADAM module目录摘要 (I)Abstract (II)第一章绪论 (1)1.1背景和意义 (1)1.2国内研究现状概述 (2)1.3 本文的主要研究内容 (3)第二章力学试验机的结构与原理 (5)2.1．试验机的基本结构 (5)2.2 热电偶测温电路的工作原理 (6)2.3 电加热炉温度控制系统的特性 (7)第三章 PID控制在力学试验机温度控制系统中的应用 (9)3.1力学试验机温度控制方案 (9)3.2 PID控制 (11)3.2.1 数字PID控制算法 (13)3.2.2 增量式的PID控制算法 (15)3.2.3 阶跃响应辩识一阶近似模型的理论与方法 (17)3.2.4 PID参数自整定 (20)3.2.5 仿真研究 (21)第四章控制系统的硬件设计与软件设计 (25)4.1硬件设计 (25)4.1.1工控机 (26)4.1.2 A/D模块 (28)4.1.3 D/A模块 (29)4.1.4固态继电器 (29)4.1.5检测元件 (31)4.2 软件设计 (32)4.2.1主控模块 (33)4.2.2实时操作与输出模块 (33)4.2.3其他输出模块 (33)第五章结束语 (34)参考文献 (35)谢辞 (37)第一章绪论1.1背景和意义力学试验机现在已经广泛应用在各个机械工厂行业中，对各个工厂的高温合金产品试样进行高温力学拉伸实验，用来测试在一定拉力和高温下金属试样力学性能的试验设备，把被测试的试样放在一定温度的炉子中，然后通过杠杆和砝码给试样施加一定的压力。
基于PLC的PID温度控制系统设计(附程序代码)
基于PLC的PID温度控制系统设计（附程序代码）摘要自动控制系统在各个领域尤其是工业领域中有着及其广泛的应用，温度控制是控制系统中最为常见的控制类型之一。
随着PLC技术的飞速发展，通过PLC对被控对象进行控制日益成为今后自动控制领域的一个重要发展方向。
温度控制系统广泛应用于工业控制领域，如钢铁厂、化工厂、火电厂等锅炉的温度控制系统。
而温度控制在许多领域中也有广泛的应用。
这方面的应用大多是基于单片机进行PID 控制, 然而单片机控制的DDC 系统软硬件设计较为复杂, 特别是涉及到逻辑控制方面更不是其长处, 然而PLC 在这方面却是公认的最佳选择。
根据大滞后、大惯性、时变性的特点，一般采用PID调节进行控制。
随着PLC功能的扩充，在许多PLC 控制器中都扩充了PID 控制功能, 因此在逻辑控制与PID控制混合的应用场所中采用PLC控制是较为合理的。
本设计是利用西门子S7-200PLC来控制温度系统。
首先研究了温度的PID调节控制，提出了PID的模糊自整定的设计方案，结合MCGS监控软件控制得以实现控制温度目的。
关键词:PLC;PID;温度控制沈阳理工大学课程设计论文目录1 引言...................................................................... (1)1.1 温度控制系统的意义...................................................................... .. (1)1.2 温度控制系统背景...................................................................... .................. 1 1.3 研究技术介绍...................................................................... .. (1)1.3.1 传感技术...................................................................... (1)1.3.2PLC .................................................................... . (2)上位机...................................................................... ............................1.3.3 31.3.4 组态软件...................................................................... ........................ 3 1.4 本文研究对象...................................................................... .. (4)2 温度PID控制硬件设计...................................................................... (5)2.1 控制要求...................................................................... .................................. 5 2.2 系统整体设计方案...................................................................... .................. 5 2.3 硬件配置...................................................................... . (6)2.3.1 西门子S7-200CUP224 ................................................................. .. (6)2.3.2 传感器...................................................................... . (6)2.3.3 EM235模拟量输入模块.....................................................................72.3.4 温度检测和控制模块...................................................................... .... 8 2.4 I/O分配表 ..................................................................... ................................ 8 2.5 I/O接线图 ..................................................................... .. (8)3 控制算法设计...................................................................... .. (9)3.1 P-I-D控制...................................................................... .............................. 9 3.2 PID回路指令 ..................................................................... .. (11)3.2.1 PID算法 ..................................................................... .. (11)3.2.2 PID回路指令 ..................................................................... (14)3.2.3 回路输入输出变量的数值转换 (16)3.2.4 PID参数整定 ..................................................................... (17)4 程序设计...................................................................... .. (19)4.1 程序流程图...................................................................... .............................. 19 4.2 梯形图...................................................................... .. (19)I沈阳理工大学课程设计论文5 调试...................................................................... . (23)5.1 程序调试...................................................................... .. (23)5.2 硬件调试...................................................................... .. (23)结束语...................................................................... .................................................... 24 附录程序代码...................................................................... ........................................ 25 参考文献...................................................................... (27)II沈阳理工大学课程设计论文1引言1.1 温度控制系统的意义温度及湿度的测量和控制对人类日常生活、工业生产、气象预报、物资仓储等都起着极其重要的作用。
数字温度计系统详细设计报告
数字温度计系统详细设计报告一设计要求1.1.系统功能要求对于设计的数字温度计系统，主要是以AT89C51(AT89C52)单片机为控制核心，采用高精度的传感器(DS18B20）对需要测量的周围温度进行周期性的测量，并用简单的通信技术，数码管显示技术，误差修正等技术，以最新的DS18B20温度传感器作为测量元件，构成一个较简单的温度测量系统。
并最终能实现对周围环境中的温度数据的精确采集，加以处理后显示在由数码管组成的显示器上。
1.2.其他要求：该测量系统尽量做到体积小、精度较高、数据传输可靠性高、功耗低、功能易扩展，对周围环境的适应性要强。
另外从经费方面除了特殊元件外，本着一切在能实现功能的基础上从简选择的原则。
2.1方案论证与选择该系统主要由温度测量和数据采集两部分电路组成，实现的方法有很多种，下面将列出两种在日常生活中和工农业生产中经常用到的实现方案（1）温度采集电路方案一采用热电偶温差电路测温，温度检测部分可以使用低温热偶，热电偶由两个焊接在一起的异金属导线所组成，热电偶产生的热电势由两种金属的接触电势和单一导体的温差电势组成。
通过将参考结点保持在已知温度并测量该电压，便可推断出检测结点的温度。
数据采集部分则使用带有A/D 通道的单片机，在将随被测温度变化的电压或电流采集过来，进行A/D 转换后，就可以用单片机进行数据的处理，在显示电路上，就可以将被测温度显示出来。
热电偶的优点是工作温度范围非常宽，且体积小，但是它们也存在着输出电压小、容易遭受来自导线环路的噪声影响以及漂移较高的缺点，并且这种设计需要用到A/D 转换电路，感温电路比较麻烦。
系统主要包括对A/D0809 的数据采集，自动手动工作方式检测，温度的显示等，这几项功能的信号通过输入输出电路经单片机处理。
此外还有复位电路，晶振电路，启动电路等。
故现场输入硬件有手动复位键、A/D 转换芯片，处理芯片为51 芯片，执行机构有4 位数码管、报警器等。
OBIS Series OBD II 检测系统 EEEA134A 产品说明书
OBD II INSPECTION SYSTEMMODEL EEEA134ABID SPECIFICATIONSCERTIFIED TEST MODE•Meets and exceeds Texas OBD II Inspection requirements.•Performs State-specified, software-controlled,automated OBD testing sequence with computer-determined pass/fail results.• Interfaces to SUN dynamometer for driveability testing (future enhancement).• Tamper-resistant, secured PC system• Automatic operation, calibration, communication and printing.• Simple vehicle OBD II interface and testing VEHICLE DIAGNOSTICS• Interfaces to Snap-Link ™ program to display live vehicle data• Interfaces to shop management system (Shopkey Information System)PC MODE• Allows operation of most IBM-compatible software programs running under WINDOWS ™ 2000.STANDARD HOST SYSTEM HARDWARE:• High performance, IBM compatible microprocessor,PENTIUM ® 900 mHz minimum*• 128 MB RAM minimum*• WINDOWS ™ 2000 operating systems • One 3.5” 1.44 MB floppy disk drive• Large-capacity hard drive, 20 GB minimum*• Disk key security • 16X DVD-ROM• 101-key enhanced keyboard• High resolution, 17” color SVGA monitor minimum*• 56,000 baud modem, minimum*STANDARD HOST SYSTEM HARDWARE (Cont’d)•High performance, non-secured laser printer •Custom-designed, easy access, secured host cabinet•Accepts user-loaded software* (Computer host system subject to enhancement as necessary)PERFORMANCE SPECIFICATIONS:•Digital, microprocessor-controlled, OBD testing •Automatic gas cap testing•High performance communication with host •Automated OBD II testing•+35° to +110° F. operating temperature range •+20° to +130° F. storage temperature range •Operates in ambient humidities up to 100%, non-condensing•Complies with SAE J-1850 OBD standard •Complies with EPA 40 CFR PART 51 as interpreted by TNRCC.STANDARD ACCESSORIES•OBD II interface module•Remote control•25’ AC power cord•25’ modem connection cable•2D bar code scanner•Fuel cap pressure tester w/adapters •Laser printerOPTIONAL CAPABILITIES (FUTURE ENHANCEMENTS)•Engine systems analyzer •Dynamometer interface•Gas analysis•Vehicle diagnostic softwarePOWER/WEIGHT/DIMENSIONS:•120V AC 60 hz 5.0 amps •Approximate shipping weight: 300 lbs.•Dimensions: 58” H x 31” W x 27” D* NOTE: Specifications are subject to change as required by various state requirements. Specifications subject to change without notice. Preliminary12/01©2001 Snap-on Tools CompanyOBD II INSPECTION SYSTEM NORTH CAROLINA MODEL EEEA135ABID SPECIFICATIONSCERTIFIED TEST MODE•Meets and exceeds North Carolina OBD II Inspection requirements.•Performs State-specified, software-controlled,automated OBD testing sequence with computer-determined pass/fail results.• Interfaces to SUN dynamometer for driveability testing (future enhancement).• Tamper-resistant, secured PC system• Automatic operation, calibration, communication and printing.• Simple vehicle OBD II interface and testing VEHICLE DIAGNOSTICS• Interfaces to Snap-Link ™ program to display live vehicle data• Interfaces to shop management system (Shopkey Information System)PC MODE• Allows operation of most IBM-compatible software programs running under WINDOWS ™ 2000.STANDARD HOST SYSTEM HARDWARE:• High performance, IBM compatible microprocessor,PENTIUM ® 1000 mHz minimum*• 128 MB RAM minimum*• WINDOWS ™ 2000 operating systems • One 3.5” 1.44 MB floppy disk drive• Large-capacity hard drive, 20 GB minimum*• Disk key security • 16X DVD-ROM• 101-key enhanced keyboard• High resolution, 17” color SVGA monitor minimum*• 56,000 baud modem, minimum*STANDARD HOST SYSTEM HARDWARE (Cont’d)•High performance, non-secured laser printer •Custom-designed, easy access, secured host cabinet•Accepts user-loaded software* (Computer host system subject to enhancement as necessary)PERFORMANCE SPECIFICATIONS:•Digital, microprocessor-controlled, OBD testing •High performance communication with host •Automated OBD II testing•+35° to +110° F. operating temperature range •+20° to +130° F. storage temperature range •Operates in ambient humidities up to 100%, non-condensing•Complies with SAE J-1850 OBD standard •Complies with EPA 40 CFR PART 51 as interpreted by North Carolina STANDARD ACCESSORIES•OBD II interface module•Remote control•25’ AC power cord•25’ modem connection cable•1D bar code scanner•Laser printerOPTIONAL CAPABILITIES (FUTURE ENHANCEMENTS)•Engine systems analyzer •Dynamometer interface•Gas analysis•Vehicle diagnostic softwarePOWER/WEIGHT/DIMENSIONS:•120V AC 60 hz 5.0 amps •Approximate shipping weight: 300 lbs.•Dimensions: 58” H x 31” W x 27” D* NOTE: Specifications are subject to change as required by various state requirements. Specifications subject to change without notice. SS2100 (5/02)©2002 Snap-on Tools CompanyOBD II INSPECTION SYSTEM PENNSYLVANIA MODEL EEEA136ABID SPECIFICATIONSCERTIFIED TEST MODE•Meets and exceeds Pennsylvania OBD II Inspection requirements.•Performs State-specified, software-controlled, automated OBD testing sequence with computer-determined pass/fail results.•Interfaces to SUN dynamometer for driveability testing (future enhancement).•Tamper-resistant, secured PC system •Automatic operation, calibration, communication and printing.•Simple vehicle OBD II interface and testing VEHICLE DIAGNOSTICS•Interfaces to Snap-Link™ program to display live vehicle data•Interfaces to shop management system (Shopkey Information System)PC MODE•Allows operation of most IBM-compatible software programs running under WINDOWS™ 2000. STANDARD HOST SYSTEM HARDWARE:•High performance, IBM compatible microprocessor, PENTIUM® 1000 mHz minimum*•128 MB RAM minimum*•WINDOWS™ 2000 operating systems•One 3.5” 1.44 MB floppy disk drive•Large-capacity hard drive, 20 GB minimum*•Disk key security•16X DVD-ROM•101-key enhanced keyboard•High resolution, 17” color SVGA monitor minimum*•56,000 baud modem, minimum*STANDARD HOST SYSTEM HARDWARE (Cont’d)•High performance, non-secured laser printer •Custom-designed, easy access, secured host cabinet•Accepts user-loaded software* (Computer host system subject to enhancement as necessary)PERFORMANCE SPECIFICATIONS:•Digital, microprocessor-controlled, OBD testing •High performance communication with host •Automated OBD II testing•+35° to +110° F. operating temperature range •+20° to +130° F. storage temperature range •Operates in ambient humidities up to 100%, non-condensing•Complies with SAE J-1850 OBD standard •Complies with EPA 40 CFR PART 51 as interpreted by Pennsylvania STANDARD ACCESSORIES•OBD II interface module•Remote control•25’ AC power cord•25’ modem connection cable•2D bar code scanner•Laser printer•Gas Cap TesterOPTIONAL CAPABILITIES (FUTURE ENHANCEMENTS)•Engine systems analyzer •Dynamometer interface•Gas analysis•Vehicle diagnostic softwarePOWER/WEIGHT/DIMENSIONS:•120V AC 60 hz 5.0 amps •Approximate shipping weight: 300 lbs.•Dimensions: 58” H x 31” W x 27” D* NOTE: Specifications are subject to change as required by various state requirements. Specifications subject to change without notice. SS2101 (5/02)©2002 Snap-on Tools Company。
(完整word版)大棚温湿度系统的设计
摘要随着大棚技术的普及,温室大棚数量不断增多，温室大棚的温度控制成为一个难题。
目前应用于温室大棚的温度检测系统大多采用由模拟温度传感器、多路模拟开关、A／D转换器及单片机等组成的传输系统。
这种温度采集系统需要在温室大棚内布置大量的测温电缆，才能把现场传感器的信号送到采集卡上，安装和拆卸繁杂，成本也高。
同时线路上传送的是模拟信号，易受干扰和损耗，测量误差也比较大，不利于控制者根据温度变化及时做出决定。
在这样的形式下.开发一种实时性高、精度高，能够综合处理多点温度信息的测控系统就很有必要。
本课题提出一种基于单片机并采用数字化单总线技术的温度测控系统应用于温室大棚的的设计方案，该方案是利用温度传感器将温室大棚内温度的变化，变换成电流的变化,再转换为电压变化输入模数转换器，其值由单片机处理，最后由单片机去控制数字显示器,显示温室大棚内的实际温度.一旦该温度值超过我们预先设定的上、下限，单片机便启动报警系统进行报警，进而对大棚内温度进行控制。
这种设计方案能对多点的温度进行实时巡检，各检测单元能独立完成各自功能，同时能够根据主控机的指令对温度进行定时采集,测量结果不仅能在本地显示，而且可以利用单片机串行口，通过RS．485总线及通信协议将采集的数据传送到计算机，进行进一步的存档、处理。
主控机负责控制指令的发送，控制各个从机进行温度采集,收集测量数据，并对测量结果(包括历史数据）进行整理、显示和存储。
该测控系统不需要任何固定网络的支持，安装简单方便，系统稳定可靠、可维护性好。
关键词；单片机；单总线技术；温度传感器；串行接口；温室大棚ABSTRACTWith the popularization of greenhouse technology，the amount of greenhouse islarger and larger．However，the temperature control of greenhouse is becoming adifficult problem．Currently,the temperature control system of greenhouse is mostlyusing a transfers system which consists of analog temperature sensors,multiplexinganalog switches，A／D conversion units and SCM．This kind of temperature collectionsystem needs a lot of cables which is laid to make the signal of the sensor be sent tothe collection card in the greenhouse．Thus the work of fixing and take-down ismiscellaneous，and the COSt is hi曲．What’S more，what is transferred in the system isanalog signals which are easily interfered and have more ullage。
O3说明书
《六西格玛案例》PPT课件
100,000 - . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•设立相应的改进目标
10,000 - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,000 - . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
多变量研究-不同厨师的面包口感
DMA I C
One-way ANOVA: Taste versus Chef
Analysis of Variance for Taste
Source DF SS MS F P
Chef 2 63.517 31.758 32.57 0.000
Error 27 26.325 0.975
我们怎样筛选导致变异的关键因素<Xs>?
SBTI/AMC Partnership 27
DMA I C ….. 筛选潜在的导致变异的因素(Xs) 我们怎样筛选导致变异的因素<Xs>?
采用流程图的输出结果 做因果矩阵 厨师、供应商、技术专家、顾客一 起打分 结果将找出"关键少数"的因素
关注"少数关键"因素
Total 29 89.842
Boxplots of Taste by Chef
Individual 95% CIs For Mean
(means are indicated by solid circles)
Based on Pooled StDe10v
Level N Mean StDev ---------+--------9-+---------+-------
维萨拉Indigo系列产品说明书
感知成功维萨拉Indigo系列DRYCAP®探头露点CARBOCAP®探头二氧化碳PEROXCAP®探头过氧化氢HUMICAP®探头油中水Insight PC 机软件气压计压力模块（可选项）Indigo300Indigo200Indigo500系列Indigo80液体浓度Polaris ™折光仪温度湿度Ref. B212707EN-A ©Vaisala 2023目 录通过维萨拉Indigo系列感知成功 (4)Indigo520数据处理单元 (9)Indigo510数据处理单元 (12)Indigo200系列数据处理单元 (15)Indigo300数据处理单元 (17)Indigo80手持式显示表头 (20)用于测量相对湿度的维萨拉HUMICAP® 传感器 (23)HMP1墙面式温湿度探头 (25)HMP3一般用途湿度和温度探头 (27)HMP4相对湿度和温度探头 (30)HMP5相对湿度和温度探头 (33)HMP7相对湿度和温度探头 (36)HMP8相对湿度和温度探头 (39)HMP9紧凑型湿度和温度探头 (42)TMP1温度探头 (45)HMP80系列手持式湿度和温度探头 (47)Vaisala DRYCAP® 传感器用于测量干燥过程中的湿度 (49)DMP5露点和温度探头 (51)DMP6露点探头 (54)DMP7露点和温度探头 (56)DMP8露点和温度探头 (58)DMP80系列手持式露点和温度探头 (61)适用于苛刻环境的维萨拉CARBOCAP® 测量传感器 (64)GMP251二氧化碳探头 (66)GMP252二氧化碳探头 (69)用于测量油中微水的维萨拉HUMICAP® 传感器 (72)MMP8油中水分探头 (74)用于测量汽化过氧化氢、相对饱和度和相对湿度的维萨拉PEROXCAP® 传感器 (76)用于过氧化氢、湿度和温度测量的HPP270系列探头 (79)34广泛的测量参数范围•湿度和温度•露点•油中水分•二氧化碳 (CO 2)•气化过氧化氢 (H 2O 2)图册通过一种新方法步入未来，以测量您关键的工业性工艺流程。
深入浅出stm32
STM32学前班教程之一：为什么是它经过几天的学习，基本掌握了STM32的调试环境和一些基本知识。
想拿出来与大家共享，笨教程本着最大限度简化删减STM32入门的过程的思想，会把我的整个入门前的工作推荐给大家。
就算是给网上的众多教程、笔记的一种补充吧，所以叫学前班教程。
其中涉及产品一律隐去来源和品牌，以防广告之嫌。
全部汉字内容为个人笔记。
所有相关参考资料也全部列出。
:lol教程会分几篇，因为太长啦。
今天先来说说为什么是它——我选择STM32的原因。
我对未来的规划是以功能性为主的，在功能和面积之间做以平衡是我的首要选择，而把运算放在第二位，这根我的专业有关系。
里面的运算其实并不复杂，在入门阶段想尽量减少所接触的东西。
不过说实话，对DSP的外设并和开发环境不满意，这是为什么STM32一出就转向的原因。
下面是我自己做过的两块DSP28的全功能最小系统板，在做这两块板子的过程中发现要想尽力缩小DSP的面积实在不容易（目前只能达到50mm×45mm，这还是没有其他器件的情况下），尤其是双电源的供电方式和1.9V的电源让人很头疼。
后来因为一个项目，接触了LPC2148并做了一块板子，发现小型的AR M7在外设够用的情况下其实很不错，于是开始搜集相关芯片资料，也同时对小面积的AVR和51都进行了大致的比较，这个时候发现了C ortexM3的S TM32，比2148拥有更丰富和灵活的外设，性能几乎是2148两倍（按照MIPS值计算）。
正好2148我还没上手，就直接转了这款STM32F103。
与2811相比较（核心1.8V供电情况下），135MHz×1MIPS。
现在用S TM32F103，72MHz×1.25MIPS，性能是DSP的66%，STM32F103R型（64管脚）芯片面积只有2811的51%，STM32F103C型（48管脚）面积是2811的25%，最大功耗是DSP的20%，单片价格是DSP的30%。
Project Builder说明
Project Builder说明：一、进入Project Builder有两种方式：1、从桌面上的快捷方式进入；2、从Start菜单中的All Programs中的Traintools中的快捷方式Project Builder进入。
二、Project Builder的内部说明1、进入Project Builder时，会要求登录并输入帐号和密码。
如下图：不登录的话，只能以访客的身份看，不能修改；登录管理员帐号才能修改程序。
2、要打开程序的话，需要先点击，然后在弹出的对话框中选择PA3_2（1线机组选择PA3_1）程序，然后点击OK按钮就会打开程序。
见下图：见上图，Save Project是保存当前程序，Get Project Revision是恢复未保存在默认目录下的程序备份的，Restore Project是恢复未保存在默认目录下的程序备份的。
默认目录是D:\TrainTools\Projects\PA3_2\Revisions按下Save Project后弹出上面的窗口，PA3_2_ZhY是起的名字，后面的数字是每次备份程序时自动生成的。
Include complied files是包含编译程序，这个勾必须要勾上。
Descrition是写描述的地方，可以不填。
按下OK键程序就会自动保存在D:\TrainTools\Projects\PA3_2\Revisions目录下。
恢复备份的话，必须先关掉TrainView和ArcCom。
按下Get Project Revision会让你选择程序备份，选择你需要的程序备份下的后缀名为.ttr的文件，如下图。
在上图中，按下Open键就会进入下一步，见下图，它显示了一些信息，按下Get就会开始恢复程序。
不想恢复程序的话，请按下Cancel。
按下Restore Revision会让你在默认目录下选择程序备份，选择后按下OK键就能自动恢复，见下图。
3、上图就是打开程序后的样子，其中Control Room是上位机；TrainView是画面；Severs是数据库服务；AlarmEvent Sever是报警事件服务器，分别连接HIMA_A和HIMA_B、SE291910；S5 Alarm/Events是CCC CPU的报警事件服务器；ArcCom是历史趋势记录服务器；ModbusOPC是将HIMA的数据连接到CCC的上位机的桥接；S5 OPC是将CCC CPU的数据连接到CCC的上位机的桥接；Script_Sever_Seletion是将SE291910的数据连接到CCC的上位机的桥接；SE291910是脚本编辑处理器，用来处理HIMA_A和HIMA_B的冗余通讯。
基于单片机的温度控制系统(英语)2
Temperature Control Using a Microcontroller:An Interdisciplinary Undergraduate Engineering Design ProjectJames S. McDonaldDepartment of Engineering ScienceTrinity UniversitySan Antonio, TX 78212AbstractThis paper describes an interdisciplinary design project which was done under the author’s supervision by a group of four senior students in the Department of Engineering Science at Trinity University. The objective of the project was to develop a temperature control system for an air-filled chamber. The system was to allow entry of a desired chamber temperature in a prescribed range and to exhibit overshoot and steady-state temperature error of less than 1 degree Kelvin in the actual chamber temperature step response. The details of the design developed by this group of students, based on a Motorola MC68HC05 family microcontroller, are described. The pedagogical value of the problem is also discussed through a description of some of the key steps in the design process. It is shown that the solution requires broad knowledge drawn from several engineering disciplines including electrical, mechanical, and control systems engineering.1 IntroductionThe design project which is the subject of this paper originated from a real-world application. A prototype of a microscope slide dryer had been developed around an OmegaTM model CN-390 temperature controller, and the objective was to develop a custom temperature control system to replace the Omega system. The motivation was that a custom controller targeted specifically for the application should be able to achieve the same functionality at a much lower cost, as the Omega system is unnecessarily versatile and equipped to handle a wide variety of applications.The mechanical layout of the slide dryer prototype is shown in Figure 1. The main element of the dryer is a large, insulated, air-filled chamber in which microscope slides, each with a tissue sample encased in paraffin, can be set on caddies. In order that the paraffin maintain the proper consistency, the temperature in the slide chamber must be maintained at a desired (constant) temperature. A second chamber (the electronics enclosure) houses a resistive heater and the temperature controller, and a fan mounted on the end of the dryer blows air across the heater, carrying heat into the slide chamber. This design project was carried out during academic year 1996–97 byfour students under the author’s supervision as a Senior Design project i n the Department of Engineering Science at Trinity University. The purpose of this paper isto describe the problem and the students’ solution in some detail, and to discuss some of the pedagogical opportunities offered by an interdisciplinary design project of this type. The students’ own report was presented at the 1997 National Conference on Undergraduate Research [1]. Section 2 gives a more detailed statement of the problem, including performance specifications, and Section 3 describes the students’ design. Section 4 makes up the bulk of the paper, and discusses in some detail several aspects of the design process which offer unique pedagogical opportunities. Finally, Section 5 offers some conclusions.2 Problem StatementThe basic idea of the project is to replace the relevant parts of the functionality of an Omega CN-390 temperature controller using a custom-designed system. The application dictates that temperature settings are usually kept constant for long periods of time, but it’s nonetheless imp ortant that step changes be tracked in a―reasonable‖ manner. Thus the main requirements boil down to·allowing a chamber temperature set-point to be entered,·displaying both set-point and actual temperatures, and·tracking step changes in set-point temperature with acceptable rise time,steady-state error, and overshoot.Although not explicitly a part of the specifications in Table 1, it was clear that the customer desired digital displays of set-point and actual temperatures, and thatset-point temperature entry should be digital as well (as opposed to, say, through a potentiometer setting).3 System DesignThe requirements for digital temperature displays and setpoint entry alone are enough to dictate that a microcontrollerbased design is likely the most appropriate. Figure 2 shows a block diagram of the students’ design.The microcontroller, a MotorolaMC68HC705B16 (6805 for short), is the heart of the system. It accepts inputs from a simple four-key keypad which allow specification of the set-point temperature, and it displays both set-point and measured chamber temperatures using two-digit seven-segment LED displays controlled by a display driver. All these inputs and outputs are accommodated by parallel ports on the 6805. Chamber temperature is sensed using a pre-calibrated thermistor and input via one of the 6805’s analog-to-digital inputs. Finally, a pulse-width modulation (PWM) output on the 6805 is used to drive a relay which switches line power to the resistive heater off and on.Figure 3 shows a more detailed schematic of the electronics and their interfacing to the 6805. The keypad, a Storm 3K041103, has four keys which are interfaced to pins PA0{ PA3 of Port A, configured as inputs. One key functions as a mode switch. Two modes are supported: set mode and run mode. In set mode two of the other keys are used to specify the set-point temperature: one increments it and one decrements. The fourth key is unused at present. The LED displays are driven by a Harris Semiconductor ICM7212 display driver interfaced to pins PB0{PB6 of Port B, configured as outputs. The temperature-sensing thermistor drives, through a voltage divider, pin AN0 (one of eight analog inputs). Finally, pin PLMA (one of two PWM outputs) drives the heater relay.Software on the 6805 implements the temperature control algorithm, maintains the temperature displays, and alters the set-point in response to keypad inputs. Because it is not complete at this writing, software will not be discussed in detail in this paper. The control algorithm in particular has not been determined, but it is likely to be a simple proportional controller and certainly not more complex than a PID. Some control design issues will be discussed in Section 4, however.4 The Design ProcessAlthough essentially the project is just to build a thermostat, it presents many nice pedagogical opportunities. The knowledge and experience base of a senior engineering undergraduate are just enough to bring him or her to the brink of a solution to various aspects of the problem. Yet, in each case, realworld considerations complicate the situation significantly.Fortunately these complications are not insurmountable, and the result is a very beneficial design experience. The remainder of this section looks at a few aspects of the problem which present the type of learning opportunity just described. Section 4.1discusses some of the features of a simplified mathematical model of the thermal properties of the system and how it can be easily validated experimentally. Section 4.2 describes how realistic control algorithm designs can be arrived at using introductory concepts in control design. Section 4.3 points out some important deficiencies of such a simplified modeling/control design process and how they can be overcome through simulation. Finally, Section 4.4 gives an overview of some of the microcontroller-related design issues which arise and learning opportunities offered.4.1 MathematicalModelLumped-element thermal systems are described in almost any introductory linear control systems text, and just this sort of model is applicable to the slide dryer problem. Figure 4 shows a second-order lumped-element thermal model of the slide dryer. The state variables are the temperatures Ta of the air in the box and Tb of the box itself. The inputs to the system are the power output q(t) of the heater and the ambient temperature T¥. ma and mb are the masses of the air and the box, respectively, and Ca and Cb their specific heats. μ1 and μ2 are heat transfer coefficients from the air to the box and from the box to the external world, respectively.It’s not hard to show that the (linearized) state equationscorresponding to Figure 4 areTaking Laplace transforms of (1) and (2) and solving for Ta(s), which is the output of interest, gives the following open-loop model of the thermal system:where K is a constant and D(s) is a second-order polynomial.K, tz, and the coefficients of D(s) are functions of the variousparameters appearing in (1) and (2).Of course the various parameters in (1) and (2) are completely unknown, but it’s not hard to show that, regardless of their values, D(s) has two real zeros. Therefore the main transfer function of interest (which is the one from Q(s), since we’ll assume constant ambient temperature) can be writtenMoreover, it’s not too hard to show that 1=tp1 <1=tz <1=tp2, i.e., that the zero lies between the two poles. Both of these are excellent exercises for the student, and the result is the openloop pole-zero diagram of Figure 5.Obtaining a complete thermal model, then, is reduced to identifying the constant K and the three unknown time constants in (3). Four unknown parameters is quite a few, but simple experiments show that 1=tp1 _ 1=tz;1=tp2 so that tz;tp2 _ 0 are good approximations. Thus the open-loop system is essentially first-order and can therefore be written(where the subscript p1 has been dropped).Simple open-loop step response experiments show that,for a wide range of initial temperatures and heat inputs, K _0:14 _=W and t _ 295 s.14.2 Control System DesignUsing the first-order model of (4) for the open-loop transfer function Gaq(s) and assuming for the moment that linear control of the heater power output q(t) is possible, the block diagram of Figure 6 represents the closed-loop system. Td(s) is the desired, or set-point, temperature,C(s) is the compensator transfer function, and Q(s) is the heater output in watts.Given this simple situation, introductory linear control design tools such as the root locus method can be used to arrive at a C(s) which meets the step response requirements on rise time, steady-state error, and overshoot specified in Table 1. The upshot, of course, is that a proportional controller with sufficient gain can meet all specifications. Overshoot is impossible, and increasing gains decreases bothsteady-state error and rise time.Unfortunately, sufficient gain to meet the specifications may require larger heat outputs than the heater is capable of producing. This was indeed the case for this system, and the result is that the rise time specification cannot be met. It is quite revealing to the student how useful such an oversimplified model, carefully arrived at, can be in determining overall performance limitations.4.3 Simulation ModelGross performance and its limitations can be determined using the simplified model of Figure 6, but there are a number of other aspects of the closed-loop system whose effects on performance are not so simply modeled. Chief among these are ·quantization error in analog-to-digital conversion of the measured temperature and· the use of PWM to control the heater.Both of these are nonlinear and time-varying effects, and the only practical wayto study them is through simulation (or experiment, of course).Figure 7 shows a SimulinkTM block diagram of the closed-loop system which incorporates these effects. A/D converter quantization and saturation are modeled using standard Simulink quantizer and saturation blocks. Modeling PWM is more complicated and requires a custom S-function to represent it.This simulation model has proven particularly useful in gauging the effects of varying the basic PWM parameters and hence selecting them appropriately. (I.e., the longer the period, the larger the temperature error PWM introduces. On the other hand, a long period is desirable to avoid excessive relay ―chatter,‖ among other things.) PWM is often difficult for students to grasp, and the simulation model allows an exploration of its operation and effects which is quite revealing.4.4 The MicrocontrollerSimple closed-loop control, keypad reading, and display control are some of the classic applications of microcontrollers, and this project incorporates all three. It is therefore an excellent all-around exercise in microcontroller applications. In addition, because the project is to produce an actual packaged prototype, it won’t do to use a simple evaluation board with the I/O pins jumpered to the target system. Instead, it’s necessary to develop a complete embedded application. This entails the choice of an appropriate part from the broad range offered in a typical microcontroller family and learning to use a fairly sophisticated development environment. Finally, a custom printed-circuit board for the microcontroller and peripherals must be designed and fabricated.Microcontroller Selection. In view of existing local expertise, the Motorola line of microcontrollers was chosen for this project. Still, this does not narrow the choice down much. A fairly disciplined study of system requirements is necessary to specify which microcontroller, out of scores of variants, is required for the job. This is difficult for students, as they generally lack the experience and intuition needed as well as the perseverance to wade through manufacturers’ selection guides.Part of the problem is in choosing methods for interfacing the various peripherals (e.g., what kind of display driver should be used?). A study of relevant Motorola application notes [2, 3, 4] proved very helpful in understandingwhat basic approaches are available, and what microcontroller/peripheral combinations should be considered.The MC68HC705B16 was finally chosen on the basis of its availableA/D inputs and PWMoutputs as well as 24 digital I/O lines. In retrospect this is probably overkill, as only one A/D channel, one PWM channel, and 11 I/O pins are actually required(see Figure 3). The decision was made to err on the safe side because a complete development system specific to the chosen part was necessary, and the project budget did not permit a second such system to be purchased should the firstprove inadequate.Microcontroller Application Development. Breadboarding of the peripheral hardware, development of microcontroller software, and final debugging and testing of a custom printed-circuit board for the microcontroller and peripherals all require a development environment of some kind. The choice of a development environment, like that of the microcontroller itself, can be bewildering and requires some faculty expertise. Motorola makes three grades of development environment ranging from simple evaluation boards (at around $100) to full-blown real-time in-circuit emulators (at more like $7500). The middle option was chosen for this project: the MMEVS, which consists of _ a platform board (which supports all 6805-family parts), _ an emulator module (specific to B-series parts), and _ a cable and target head adapter (package-specific). Overall, the system costs about $900 and provides, with some limitations, in-circuit emulation capability. It also comes with the simple but sufficient software development environment RAPID [5].Students find learning to use this type of system challenging, but the experience they gain in real-world microcontroller application development greatly exceeds the typical first-course experience using simple evaluation boards.Printed-Circuit Board. The layout of a simple (though definitely not trivial) printed-circuit board is another practical learning opportunity presented by this project. The final board layout, with package outlines, is shown (at 50% of actual size) in Figure 8. The relative simplicity of the circuit makes manual placement and routing practical—in fact, it likely gives better results than automatic in an application like this—and the student is therefore exposed to fundamental issues of printed-circuit layout and basic design rules. The layout software used was the very nice package pcb,2 and the board was fabricated in-house with the aid of our staff electronics technician.5 ConclusionThe aim of this paper has been to describe an interdisciplinary, undergraduate engineering design project: a microcontroller- based temperature control system with digital set-point entry and set-point/actual temperature display. A particular design of such a system has been described, and a number of design issues which arise—from a variety of engineering disciplines—have been discussed. Resolution of these issues generally requires knowledge beyond that acquired in introductory courses, but realistically accessible to advance undergraduate students, especially with the advice and supervision of faculty.Desirable features of the problem, from a pedagogical viewpoint, include the use of a microcontroller with simple peripherals, the opportunity to usefully apply introductorylevel modeling of physical systems and design of closed-loop controls, and the need for relatively simple experimentation (for model validation) and simulation (for detailed performance prediction). Also desirable are some of the technologyrelated aspects of the problem including practical use of resistive heaters and temperature sensors (requiring knowledge of PWM and calibration techniques, respectively), microcontroller selection and use of development systems, and printedcircuit design.AcknowledgementsThe author would like to acknowledge the hard work, dedication, and ability shown by the students involved in this project: Mark Langsdorf, Matt Rall, PamRinehart, and David Schuchmann. It is their project, and credit for its success belongs to them. References[1] M. Langsdorf, M. Rall, D. Schuchmann, and P. Rinehart,―Temperature control of a microscope slide dryer,‖ in1997 National Conference on Undergraduate Research,(Austin, TX), April 1997. Poster presentation.[2] Motorola, Inc., Phoenix, AZ, Temperature Measurementand Display Using the MC68HC05B4 and the MC14489, 1990. Motorola SemiconductorApplicationNote AN431.[3] Motorola, Inc., Phoenix, AZ, HC05 MCU LED Drive Techniques Using the MC68HC705J1A, 1995. Motorola Semiconductor Application Note AN1238.[4] Motorola, Inc., Phoenix, AZ, HC05MCU Keypad Decoding Techniques Using the MC68HC705J1A, 1995. Motorola Semiconductor Application Note AN1239.[5] Motorola, Inc., Phoenix, AZ, RAPID Integrated Development Environment User’s Manual, 1993. (RAPID wasdeveloped by P & E Microcomputer Systems, Inc.).。
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温度计的设计（I）
一、课程目的
1．加深对电路分析、模拟电路、数字逻辑电路等相关课程理论知识的理解；
2．掌握电子系统设计的基本方法和一般规则；
3．熟练掌握电路仿真方法；
二、设计任务
1．设计并制作一个数字温度计，温度传感器选用负温度系数的热敏电阻。
2．（1）基本要求
实验中，用所实现的数字温度计测量室温和杯内水的温度，并用给定的数字温度表做校验标准，调整和检验所设计的温度计的测量误差。
要求测量的温度范围为
20~50℃时，显示精度为0.1℃，测量误差不大于2℃。
热敏电阻的典型特性如表
所示。
要求在20~50℃范围内测量误差不大于1℃，显示精度为0.1℃。
三、任务说明：
测温传感器的种类也很多，例如热电偶、金属热电阻、半导体热敏电阻、集成温度传感器、智能化温度传感器、红外辐射温度传感器、红外辐射温度传感器等，它们有各自适用的测温范围，测量精度和用途。
导体热敏电阻具有灵敏度高、体积小和反应速度等特点。
半导体热敏电阻有多种类型，适合连续温度测量用的是具有负温度系数（NTC）的热敏电阻，温度越高，其阻值越小，且阻值与温度的关系是非线性的。
数字温度计的原理框图如下图所示。
Rt
数字式温度计电路原理框
图中，通过热敏电阻和相应的电路将温度变化转化为电压信号，放大后先送至线性校正电路。
由于所用的热敏电阻的阻值和温度的关系是非线性的，为使电路显示出准确的温度值，须将热敏电阻的非线性特性通过校正电路转换电压随温度线性变化。
由线性校正电路输出的电压信号送至模数转换电路，转换成数字信号，去驱动显示电路，显示出被测温度值。
热敏电阻的阻值和温度的关系，也可以采用查表的方法找出。
由于实验器件有限，并考虑使学生收到全面训练，建议自己设计模数转换电路，而不要采用通用模数转换芯片。
四、验收要求：
1．仿真图的验收；
2．撰写并提交报告；
温度计的设计（II~III）
一、课程目的
1．加深对电路分析、模拟电路、数字逻辑电路、微处理器等相关课程理论知识的理解；
2．掌握电子系统设计的基本方法和一般规则；
3．熟练掌握电路仿真方法；
4．掌握电子系统的制作和调试方法；
二、设计任务
1．在（I）的基础上改进系统，加入微处器，具体原理框图如下：（基本要求）
2．能够设置上下限温度范围和超限报警功能；（基本要求）
3．语音播报功能；（进阶要求）
4．其他特色和创新；（进阶要求）
三、验收说明
1．电路检查；
2．撰写并提交报告；。