电气工程专业毕业设计论文-基于ATmega16单片机变压器保护装置设计

大学

毕 业 设 计

题 目 基于ATmega16单片机变压器保护装置设计 专 业 班 级 学 生 学 号 指导教师

二〇一 四 年 五 月 五 日

大学毕业设计论文 摘 要

摘 要

变压器作为联系不同电压等级网络的设备，是电力系统中非常重要的元件。变压器的安全运行关系到整个电力系统供电的可靠性。随着变压器电压等级和容量的提高，变压器本身也越来越贵重。因此变压器保护显得尤为重要，如何能够快速准确的切除变压器故障，使损失降低到最小，同时又要保证有足够的可靠性，就成了变压器保护的主要问题。

本文就此问题对当前变压器出现的各种故障及相应的保护原理进行了简要分析，并在此基础上对变压器保护装置进行了简单设计。该设计的硬件部分以ATmega16为系统的核心，通过对温度、电压及电流进行数据采集并送入信号处理电路，从而准确地得到控制系统可以识别的数字信号。

该设计的软件部分介绍了三种AVR单片机的应用软件，并对系统的主要流程作出了说明，讲述了单片机如何对处理得到的数字信号进行监视、判断处理，及时对各种保护装置发出声光报警或跳闸信号，进而更好地提高变压器运行的安全性和可靠性，确实做好变压器保护工作。

关键字： 变压器保护 微机保护 单片机 差动保护

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大学毕业设计论文 Abstract

Applications of Single chip in Transformer Protection

Abstract

As the equipment contacts various voltage grade networks, the transformer is one of the important elements in the electrical power system. The transformer running whether in security has relation to the reliability of whole electrical power system. With transformer voltage grade and capacity increase year after year, the transformer more and more expensive. Thus transformer protects bulk more important. In order to reduce the losses to the minimum and ensure there is sufficient reliability, how to clear the transformer faults quickly and accurately becomes the main problem of transformer protection.

On this issue, the paper gives a brief analysis to the faults of transformer and the corresponding protection principle. And on the basis of this, carry out a simple design of transformer protective device. The design of hardware takes ATmega16 as the core, collecting the temperature, voltage and current and sending to signal processing circuit to obtain the digital signal that control system can identify accurately.

The design of software introduces three kinds of application software and shows the main flow chart of the system, explains how the SCM to monitor and judge the digital signals had handled, send sound and light alarm or tripping signal to the protective device promptly, which serves to improve the operation of the transformer safely and reliability better, really do a good job on transformer protection.

Keywords: transformer protection microcomputer-based protection

SCM differential protection

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大学毕业设计论文 目 录

目 录

第一章 绪论 ........................................................................................................ 1

1.1 课题背景及意义 .................................................................................... 1

1.2 变压器微机保护的发展及现状 ............................................................ 2

1.3 论文的主要工作 .................................................................................... 3

第二章 变压器故障分析 .................................................................................... 4

2.1 变压器的基本原理及分类 .................................................................... 4

2.2 变压器的基本结构 ................................................................................ 5

2.3 变压器故障类型及不正常运行状态 .................................................... 6

2.4 变压器保护配置原则 ............................................................................ 6

第三章 变压器保护原理分析 ............................................................................ 8

3.1 变压器保护的基本要求 ........................................................................ 8

3.2 变压器保护原理分析 ............................................................................ 9

3.2.1 变压器瓦斯保护 .......................................................................... 9

3.2.2 变压器电流速断保护 ................................................................ 10

3.2.3 变压器差动保护 .........................................................................11

3.2.4 变压器相间短路后备保护 ........................................................ 12

3.2.5 变压器零序电流保护 ................................................................ 14

第四章 变压器保护装置的硬件设计 .............................................................. 15

4.1 微机保护的基本原理及其特点 .......................................................... 15

4.2 微机保护装置的构成 .......................................................................... 15

4.3 变压器保护装置主系统的硬件设计 .................................................. 16

4.3.1 ATmega16微处理器 ................................................................. 17

4.3.2 多路模拟开关CD4051 ............................................................. 18

4.3.3 温度采集系统 ............................................................................ 20

4.3.4 电压电流采集系统 .................................................................... 21

4.3.5 采样保持电路 ............................................................................ 27

4.3.6 ADC转换原理 .......................................................................... 28

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