eaintheaccidentinvestigation,managementandreporting,eachpostshouldbedevelopedunderthissystemspecialistscheck,cleartheexaminations,time,cyclesandotherrelevantregulations.Strengtheningsitesupervisionandexamination,todetectandinvestigateillegalcommand,illegaloperationsandviolationsofoperatingrules.Secondsafetyreferstotheproductionsite,technologymanagement,equipment,facilities,andsooncanleadtoaccidentsrisksexist.1,accordingtotheextentofthesecurityrisks,solvingisdividedintoa,b,andclevelsofdifficulty;A-level:difficult,miningdifficulties,shallbereportedtothecompany'sproblems.B-class:difficulttoresolvedif
iculties,shallconsistofminingorganizationstosolveproblems.C-class:fromsegmentsandbusinessrisksthatmustbeaddressedintheDepartment.2,open-pitmine
(设计)
题 目 单相电子预付费电度表设计
学生姓名
学 号
院 系 专 业 电气工程与自动化
指导教师
二Ｏ 年 月 日
nclude:electrical,transport,blasting,fire,andotherslope.3,accordingtotheseverityofthehazardfilledinbyunittroubleshooting,registrationform(seeatt毕业论文
unsafetypesieaintheaccidentinvestigation,managementandreporting,eachpostshouldbedevelopedunderthissystemspecialistscheck,cleartheexaminations,time,cyclesandotherrelevantregulations.Strengtheningsitesupervisionandexamination,todetectandinvestigateillegalcommand,illegaloperationsandviolationsofoperatingrules.Secondsafetyreferstotheproductionsite,technologymanagement,equipment,facilities,andsooncanleadtoaccidentsrisksexist.1,accordingtotheextentofthesecurityrisks,solvingisdividedintoa,b,andclevelsofdifficulty;A-level:difficult,miningdifficulties,shallbereportedtothecompany'sproblems.B-class:difficulttoresolvedif
单相电子预付费电度表设计
摘要：电度表作为现今普遍电能计量工具，鉴于微控制器和大规模集成电路的引入，对相关的电路的熟知以及能够设计还有对系统的主要硬件电路设计的工作电路及其相应的基本原理的了解以及掌握。为设计达到比普通计量器更具有优势，需要能对其系统电路的分析和设计。而本文介绍了单相电子预付费电度表的工作原理、硬件组成及其实现的功能，并给出了硬件电路。 关键词：单片机及集成电路，电表设计
Single-Phase Electronic Prepaid Watt-hour Design
Abstract: Meter as the current energy measurement tool, given the micro-controller and the introduction of large scale integrated circuit , circuit related to the need for well-known and still be able to design the hardware for the system's main circuit design of the circuit and its corresponding basic working principles of understanding and control . For the design to meter more than ordinary advantage need to able to its system circuit analysis and design . The article describes the single-phase electronic prepaid watt-hour meter works ,hardware components and their functions to achieve ,and gives the hardware circuit. Key word : SCM IC meter design
0 引言
为了让用户在使用电表方面更加方便，为此设计了一款方便迅捷的电度表。一般传统设计的电表需要抄表人员定期挨家挨户抄取数据，结算出费用后，再到各家索取，误差大、统计工作量大，人为的错误给电力部门和用户带来极大不便，也造成了用户和电力部门的纠纷。因此我设计了利用单片机作为控制器的IC卡预付费式电度表，而且微控制器和大规模集成电路在电能计量领域的广泛应用，也使的这一设计更加合理化。同时本设计作为一种智能化的家居电气，也给人们生活带来了诸多的便利，这无疑促使它在现在的生活节奏中更具有优势。
1 系统主要硬件电路设计
1.1 系统硬件总设计图
iculties,shallconsistofminingorganizationstosolveproblems.C-class:fromsegmentsandbusinessrisksthatmustbeaddressedintheDepartment.2,open-pitmineunsafetypesinclude:electrical,transport,blasting,fire,andotherslope.3,accordingtotheseverityofthehazardfilledinbyunittroubleshooting,registrationform(seeatteaintheaccidentinvestigation,managementandreporting,eachpostshouldbedevelopedunderthissystemspecialistscheck,cleartheexaminations,time,cyclesandotherrelevantregulations.Strengtheningsitesupervisionandexamination,todetectandinvestigateillegalcommand,illegaloperationsandviolationsofoperatingrules.Secondsafetyreferstotheproductionsite,technologymanagement,equipment,facilities,andsooncanleadtoaccidentsrisksexist.1,accordingtotheextentofthesecurityrisks,solvingisdividedintoa,b,andclevelsofdifficulty;A-level:difficult,miningdifficulties,shallbereportedtothecompany'sproblems.B-class:difficulttoresolvedif液晶显示器 IC卡接口 单片微处理器MCU 电能计量专用电路 分压器和分流器 断电机构
1.2 有功电能测量的基本原理
电度表由分压器取得电压信号，电流互感器取得电流采样信号，经乘法器得到电压电流乘积信号，再经频率变换产生一个频率与电压电流乘积正比的电能计量脉冲，就容易计量处电能。
电度表采用了专用集成电路SM9903.SM9903芯片包含四象模拟乘法器、积分器、电压/频率转换器VFC、计数器（分频器）及控制逻辑。
在正弦稳态情况下，设正弦电压和电流分别为：
u?2Ucos?t (1)
i?2Icos(?t??) (2)
式中，u为交流电压瞬时值，i为交流电流瞬时值，U为交流电压有效值，I为交流电流有效值，?为交流电的角频率，?=?u-?i为电压电流的相位差。
经四象限模拟乘法器相乘后的瞬时功率为：
p?ui?2Ucos?t*2Icos(?t??)?UI[cos??cos(2?t??)] （3）
可见，瞬时功率有恒定分量UI率是电压（或电流）频率的两倍
cos?和正弦分量两面三量两面三刀部分，正弦分量的频
iculties,shallconsistofminingorganizationstosolveproblems.C-class:fromsegmentsandbusinessrisksthatmustbeaddressedintheDepartment.2,open-pitmineunsafetypesinclude:electrical,transport,blasting,fire,andotherslope.3,accordingtotheseverityofthehazardfilledinbyunittroubleshooting,registrationform(seeatt