户用超声波热量表

论文编号:ZD1244  论文字数:21893,页数:38  附原理图，外文翻译

摘 要
 该热量表用于采暖热能计量，是住宅、工厂、学校、商店、医院、矿山等企事业单位以水为热媒的供暖系统的入户计量仪表。
 该热量表是根据进水和出水的温度差，并测出热水的流量来计算热量。温度测量采用DS18B20数字温度传感器，两个配对温度传感器分别测量进水温度和出水温度，得到温差，流量测量采用超声测量技术，使用超声波换能器产生超声波和接受超声波。由单片机控制发送超声波的频率和发射时间，经过谐振电路和压电陶瓷片产生机械振动，产生超声波，利用频差法，求得水的流量。
 这种热量测量系统采用嵌入系统，具有耗能低、非接触、对温度与压力等各项参数能进行自动校正等功能。实验表明：这种热量计测量精度达1.5级，且具有结构简单、成本低及实用性强等优点。
关键词：热量表；超声波；温度传感器；频差法；单片机

Abstract
 The calories'' watch used for adopting the warm thermal energy to calculate, is the business units, such as residence, factory, school, store, hospital and the mineral mountain. to take water as the hot to provide the warm system into the door to calculate the appearance.
 The calories'' form according to enter the temperature of the water and water bad, and test to find out the discharge of the hot water to compute the calories. The temperature measures to adopt the platinum electric resistance temperature to spread the feeling machine, two form couples the temperature to spread the feeling machine to measure into the water temperature degree and a water temperature degrees respectively, getting the difference in temperature, the discharge measures to adopt a diagraph technique, using a wave to change the ability machine to produce a wave and accept a wave. Send out the frequency of a wave and shoot time from a machine control, flap the electric circuit and press to give or get an electric shock a creation machine vibration through, produce a wave, make use of the bad method, the discharge that beg the water.
 This kind of calories measures the system adoption to imbed the system, having the ability of consume low, get in touch with not and can carry on the au to correct etc. to various parameters, such as temperature and pressure. function. Experiment the enunciation: This kind of calorimeter measures the accuracy to amount to 1.5 classes, and have the structure simple, the cost is low and the function strong etc. advantage.
Key Words: Heat meter ; Ultrasonic; Wireless Sensor；Frequency difference；single chip processor

目     录
1.1 方案论证及设计背景   5
2.1 热量表设计简介   6
2.2 热量表微控制器的简介   6
    2.2.1MSP430系列单片机简介   6
    2.2.2MSP430F135单片机简介   7
    2.2.3MSP430F135的晶体时钟模块   8
2.3 热量表工作模式的设计   9
    2.3.1MSP430的工作模式   9
    2.3.2工作模式的设置   9
    2.3.3工作模式在热量表中的应用  10
2.4 热量表的定时器设计  11
    2.4.1定时器简介  11
    2.4.2定时器的操作  11
    2.4.3热量表中定时器的应用  11
2.5 热量表测温模块设计  12
    2.5.1总体方案设计  12
    2.5.2 DS18B20数字温度传感器介绍·  13
    2.5.3硬件连接  14
    2.5.4软件设计  15
2.6 热量表流量数据采集的设计  16
    2.6.1 SB5227型智能化超声波计量专用集成电路介绍  16
    2.6.2超声波流量计的基本原理及类型  17
    2.6.3总体方案设计  19
    2.6.4硬件设计  20
    2.6.5软件设计  21
2.7 热量表中计算模块设计  21
    2.7.1热能计算公式  21
    2.7.2数据转换设计  22
2.8 热量表的数据安全模块设计  22
    2.8.1概述  22
    2.8.2 Flash存储器  23
    2.8.3具体实现  24
2.9 热量表串行通信模块设计  25
    2.9.1方案设计  25
    2.9.2串行通讯接口介绍  25
    2.9.3 USART介绍  28
    2.9.4具体实现  28
2.10 单频音报警接口  28
2.11 液晶显示器LCD显示的工作原理  29
2.12 热量表整体设计  30
    2.12.1热量表的软件整体流程图  30
    2.12.2热量表设计中所注意的问题  30
    2.12.3热量表的特点  31
致谢·  32
参考文献·  33
附录·  34