论文编号:JD624 包括任务书,开题报告,原理图,论文字数:31226,页数:74
摘 要
在当今各种工业企业的动力设备中,锅炉仍然是一重要的组成部分。随着现代化工业的飞速发展,对能源利用率的要求越来越高,作为将一次能源转化为二次能源的重要设备之一的锅炉,其控制和管理随之要求越来越高。但在我们国家,除了一些大中型锅炉采用了先进的控制技术外,绝大多数中小企业所用的锅炉,如10T/h、20T/h锅炉,大部分还在采用仪表/继电器控制,甚至还是人工操作,已无法满足要求。据此,本文针对一台10T/h工业锅炉,提出了一套PLC的控制系统方案。
本文以一台10T/h锅炉的PLC控制系统为背景,理论与实践相结合,详细阐述了集PLC技术,变频器技术,通信技术于一体的先进控制技术在该锅炉控制系统中的应用。在该系统中,应用了Siemens公司的S7-300系列PLC,根据锅炉的控制特点,分析系统的控制要求,实现给煤自动调节,送风自动调节,引风自动调节,水泵给水的自动调节,根据系统控制要求分析系统所需的PLC配置,以及备控量的I/O点数及I/O口分配,查阅S7-300使用手册在理论上分析确定PLC的组成及使用事项,并用其编程软件Step7设计锅炉控制的梯形图、STL语句及PLC通信网络,实现锅炉的水位三冲量控制、燃烧过程自动控制、蒸汽压力自动控制等功能;基于锅炉运行安全的考虑,该系统中锅炉由PLC控制, PLC、上位机组成一个MPI网,运用Siemens公司的MPI全局通讯技术及WinCC的软件设计,实现锅炉的上位机的冗余控制,
关键词:锅炉 变频器 PLC PID WinCC Step7 MPI 全局通讯
Abstract
Nowadays the boilers are still an important component among various power equipments in industrial enterprises. Along with the fast development of modem industry,high efficient energy utilization is pursued more and more. And the boiler are a kind of Primary equipments for converting raw energy into secondary energy,so their control and supervision is very important for promoting energy utilization efficiency. But in our country,only some big and medium-sized boilers have adopted. Advanced control technique. Most boilers being used by medium and small enterprises,such as 10T/h and 20T/h boilers,are controlled by mete/relays,or even manually. That can not meet demand. In this paper,a control system scheme of PLC+IPC is Proposed,which is aiming at a 10T/h industrial boilers.
An advanced boiler control technique composed of PLC,inverter,and communication are detailly described with respect theory and application in this paper,which is based on two PLC control systems of 10T/h boilers in certain plant. The S7-300 series PLC of siemens company is adopted in the boiler control systems. The Step7 programming software is used to design the ladder chart,the STL language and the PLC correspondence network. Automatic control for the boilers has been realized,such as three impulse control for the water level,burning Process control,vapor pressure control. Moreover,an amicable man-machine interface,automatic storage of important boiler run data,and automatic print of reports in need is realized by using the configurations software WinCC of Siemens company. Each boiler in the system is controlled by one PLC respectively. PLC and IPC shaped into a MPI net. By using the MPI overall situation telecommunication technique and the WinCC software of Siemens company redundancy controls of the two IPC are designed for the safety. The automatic control of public facilities such as deoxidization equipment is also realized in the system.
Key words: boiler,inverter,PLC,PID
目录
摘 要 I
Abstract II
第一章 绪论 1
1.1 工业锅炉控制现状 1
1.2 工业锅炉控制的任务和特点 1
1.3 PLC控制的优点 7
1.4本文主要内容 8
第二章锅炉控制系统的总体设计 9
2.1系统控制要求 9
2.2 锅炉本体构造 9
2.3 系统设计思想 10
2.3.1电机控制模式 10
2.4各主要回路控制策略 12
第三章 系统硬件组成 20
3.1总体结构 20
3.2 系统硬件组成 20
3.3主要器件选择 20
3.4系统供电 33
3.5系统接地 34
3.6 系统运行方式 34
3.7 PLC配置及I/O点分配: 35
第四章系统软件和设置 42
4. 1 PLC软件设计 42
4.2系统通讯 56
4.3 本章小结 57
结束语 58
致谢 59
参考文献 60
附录1 61
附录2 62
附录3 65