发电厂燃煤锅炉燃烧单片机控制系统设计 - 图文

摘要

热电厂锅炉的燃烧控制对整个发电过程的安全性与经济性起着重要的作用，所以对它高效率的控制是现在热电厂的一个重要任务。本文通过对整个燃烧系统的分析和研究，分别确定了锅炉燃烧控制系统中的主蒸汽压力控制系统和炉膛负压控制系统的控制方案，然后对其控制规律及参数进行选择和整定。在仪表选型时，采用了先进的数字式仪表，并利用AT89S51单片机设计了一套智能燃烧控制系统,给出了硬件电路和软件流程图。该控制器以新型的AT89S51单片机为核心,采用模糊PID算法进行运算和控制,不但可以实现对模拟、数字信号进行采样和处理,而且还可以完成状态检测和控制、报警以及故障处理等功能。该控制系统具有速度快、精度高、可靠性高和硬件结构简单的特点。最后可达到锅炉安全、经济、高效的运行。

关键词:热电厂；锅炉燃烧；单片机；控制

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Abstract

Thermal power plant boiler combustion control plays an important role in security and economy of the entire power generation process, the control of its high efficiency thermal power plant is an important task. In this paper, the analysis and study of the entire combustion system, the boiler combustion control system, main steam pressure control system and the furnace pressure and control system control program, then its control law and parameter selection and tuning. Instrument selection, using advanced digital instrument, and using the AT89S51 microcontroller design an intelligent combustion control system, given the hardware and software flow chart. The controller to the new AT89S51 MCU as the core, the use of fuzzy PID algorithm for computing and control, not only can be analog, digital signal sampling and processing, but also to complete the state detection and control, alarm and fault handling functions. The control system has a fast, high precision, high reliability and a simple hardware structure. Finally, you can reach the boiler safe, economical and efficient operation.

Keywords: heat and power plant; boiler combustion; microcontroller; control

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目录

1 绪论............................................................................................................................................. 1

1.1 研究背景 ........................................................................................................................... 1 1.2 研究意义 ........................................................................................................................... 1 1.3 国内外研究现状 ............................................................................................................... 2 1.4 主要研究内容 ................................................................................................................... 3 2 燃煤锅炉系统的总体设计方案 ................................................................................................. 4

2.1 锅炉燃烧的生产工艺 ....................................................................................................... 4 2.2 燃煤锅炉系统控制设计方案 ........................................................................................... 5

2.2.1 汽包水位控制 ....................................................................................................... 6 2.2.2 炉膛负压控制 ....................................................................................................... 7 2.2.3 蒸汽压力控制 ....................................................................................................... 8 2.2.4 炉膛温度控制系统 ............................................................................................... 9

3 温度控制系统硬件电路设计 ................................................................................................... 11

3.1 单片机的介绍和芯片的选型 ......................................................................................... 11

3.1.1 单片机简介 ......................................................................................................... 11 3.1.2 芯片的选型 ......................................................................................................... 12 3.2 AT89S51单片机的基本结构 .......................................................................................... 12

3.2.1 AT89S51单片机的主要特征 .............................................................................. 12 3.2.2 AT89S51单片机的引脚介绍 .............................................................................. 13 3.3 DS18B20温度传感器 ...................................................................................................... 15 3.4 系统硬件电路设计 ......................................................................................................... 17

3.4.1 单片机最小系统电路 ......................................................................................... 17 3.4.2 显示电路 ............................................................................................................. 18 3.4.3 温度控制及报警电路 ......................................................................................... 19 3.4.4 DS18B20温度传感器电路 .................................................................................. 19

4 温度控制系统软件设计 ........................................................................................................... 20

4.1 系统软件设计整体思路 ................................................................................................. 20 4.2 系统程序流图 ................................................................................................................. 21

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