摘要：随着国民经济的增长的需要，我国电网覆盖面积日益扩大，为了提高供电系统的稳定性，备自投作为提高稳定性的自动投入装置已成为研究的重要课题。当正常供电的工作电源由于电源本身故障或其他原因断电时，可依靠备用电源自动投入装置BZT迅速将备用电源投入，使供电系统恢复正常供电，以提高供电电源的可靠性。本设计以可编程逻辑控制器PLC为核心，将装置的各种大量的输入、输出模拟量，开关量通过虚拟逻辑编程，进行图形直观式编程整定，设计实现了一种简单，灵活实用的BZT。设计包括控制流程图的设计，缺相检测设计，以及控制模块设计。备自投的设计大幅度降低了设备的运行、维护成本，提高了供电系统的安全性。65374

毕业论文关键词：可编程逻辑控制器；备自投；电网

Abstract: Along with the growth of the national economy, China's network coverage is increasing, in order to improve the stability of power supply system, prepared from the cast as theautomatic input device of improving stability has become an important research topic.

When the normal power supply works due to the power source itself or other reasons power fails, can rely on the reserve power source automatic input device of BZT quickly to the standby power supply, the power supply system to restore normal power supply, in order to improve the reliability of power supply.The design of the programmable logic controller PLC as the core device, a variety of input, output, switch quantity through the virtual logic programming, graphics and visual programming setting, the design and implementation of a simple, flexible and practical BZT. The design includes the design of a control flow graph, phase detection is designed, and the control module design. Preparation of self design greatly reduces the investment of the equipment operation, maintenance cost, improve the safety of the power supply system.

Key words: Programmable Controllers；BZT；Power Grid

目录

1 前言 4

1.1本设计的背景意义 4

1.2本设计的主要内容 5

2 备自投概述 5

2.1 备自投简介 5

2.2 备自投的工作原理 5

2.3 备自投的基本功能 6

2.4 备自投的投入方式 7

2.5 备自投的操作要求 9

3 PLC技术简介 10

3.1 PLC的技术概述 10

3.2 PLC的系统组成 10

3.3 PLC的工作原理 11

3.4 PLC的功能特点 12

3.5 PLC的编程语言 13

3.6 PLC的基本逻辑指令 14

4 备自投方案设计 18

4.1 设计思路 18

4.2 三相电源的缺相检测回路设计 20

4.3备自投电气原理接线图设计 21

4.4 PLC的I/O设计 22

4.5 备自投的PLC接线图 23

4.6 PLC程序设计 24

5 实验 26

结  论 27