1、 I 摘摘 要要 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
2、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
3、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 II Abstract Nowadays the boilers are still an important component among various power equipments in industrial enterprises. Along with the fast development of modem industry,h
4、igh 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
5、 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 10
6、T/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 fo