基于射频卡预付费单相电能表的设计【毕业作品】

B I YE SHE JI

（20届）

基于射频卡预付费单相电能表的设计

所在学院

专业班级自动化

学生姓名学号

指导教师职称

完成日期年月

摘要

本设计是一基于射频卡的预付费单相电能表，能够实先买电后用电、阶梯计电、提示买电等功能。当用户不买电时，电能表能够自动断电；只有用户买电并由电能表读取后，用户才能用电。

由于资源日益紧缺，人们的环保意识逐渐增强，节约成为我们必须要重视的课题。在本设计中，通过阶梯计电价的功能，可以提高人们的节约意识。在本设计中还设有声光报警，声光报警可以提示用户买电，这方便了用户。此电能表还可实现先买电后用电的功能，解决供电部门收费难的问题。

文中给出了射频卡预付费电能表硬件设计的思路。讨论了单片机的资源分配、射频卡的读写、电能计量、液晶显示等问题，并给出了相应的设计原理，着重对射频卡的读写模块进行了描述。

根据电能表需要实现的功能，本设计中还给出了系统的软件，画出了射频卡预付费电能表功能实现的主流程。对射频读写模块、电能计量模块、液晶显示模块中的软件设计给出了设计思路、关键流程。

文中对基于硬件设计基础和软件技术进行测试过程中出现一些问题提出方法加以解决。提出一些方案避免可能出现的干扰问题，对使用过程中可能出现的误差加以分析，提出方案提高精度，减小误差。

关键词：预付费，射频卡，单片机

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Abstract

The design is a system that based RF card prepayment meter, it can be able to make users buy electricity before use it, ladder billing, suggesting us to buy the electricity and so on. When the user does not buy electricity, the power meter can power-off automatically; only users buy electricity by the power meter read, the user can use electricity.

Due to increasing scarcity of resources, people's environmental awareness is gradually increased, and saving has been the important issue we must notice. In this design, this function that the ladder billing of electricity can improve the awareness of saving. This design also features audible and visual alarm, it can prompt the users to buy electricity, make users more convenient. This power meter has function that let people buy electricity before use it to solve the difficult problem of charging for electricity.

This paper presents the hardware design ideas of RF card prepayment meter, discusses how allocate resources of the microcontroller, RF card reader, energy metering, LCD and other issues, and gives the design principles, focusing on RF card reader module. According to the functions of the power meter, this design gives the system software, draw the main process of RF card prepaid meter. And it gives us the software of RF card module, power metering module, LCD module, their designing ideas, key processes.

I find some problems by testing based on the hardware design and software technology and propose ideas to solve them. Propose some solution to avoid possible interference issues. Analyze for possible errors in the process of using, developed method to improve accuracy, reduce error.

Keywords: prepaid, RF card, microcontroller

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目录

摘要 .................................................................................................................. I Abstract............................................................................................................... II 目录 ................................................................................................................ III 第一章绪论 (1)

1.1 课题研究的目的和意义 (1)

1.2 电能表的历史与现状 (1)

1.3 电能表的分类 (4)

1.4 感应式和电子式电能表的性能对比 (5)

1.5 射频卡电子式预付费电能表优点 (7)

1.6 设计内容 (7)

1.7 系统框图 (8)

第二章RFID技术 (9)

2.1 RDID技术介绍 (9)

2.2 RFID系统基本组成 (9)

2.3 RFID技术发展历史 (9)

2.3 RFID技术国内外发展状况 (10)

2.4 射频卡的分类 (11)

2.5 Mifare1 S50射频卡 (12)

第三章预付费电能表硬件研究与设计 (15)

3.1 单片机 (15)

3.2 射频读写电路 (15)

3.3 电能计量模块 (18)

3.4 电源模块 (19)

3.5 显示模块 (20)

3.6 其它功能模块 (21)

3.7 本章小结 (22)

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