【作者】 陆文一；

【导师】 田作华； 王培云；

【作者基本信息】 上海交通大学 ， 控制工程， 2011， 硕士

【摘要】 随着现代工业技术的飞速发展,对能源利用率的要求越来越高。锅炉作为将一次能源转化成二次能源的重要设备之一,其控制和管理水平也日趋提高。燃烧器是锅炉燃烧系统的核心和最大能耗部件,有必要设计先进的燃烧控制系统实现锅炉在最优的空燃比下高效燃烧,从而实现节能环保。本文以某炼油公司自备发电厂所用5台75t/h燃油燃气锅炉燃烧控制为课题,在研究总结现有燃烧控制原理的基础上,改进了基于笔者所在公司生产的燃烧器的控制方法,提出了多种燃料掺烧的控制设计方案,并搭建基于西门子S7-300PLC软冗余环境下的燃烧控制系统软硬件平台。本文主要在以下四个方面开展研究:1.设计了基于西门子S7-300PLC软冗余环境下的燃烧管理系统(BMS),该系统由冗余、火检与点火系统构成,可完成点火、吹扫、火焰检测、主燃料阀开闭及燃料切换管理、燃油压力、燃气压力等故障开关量检测与安全保护等功能。2.根据工程要求,设计上引入了冗余热备份控制技术,当一台控制器或电源出现故障时,系统能自动切换到另一台备用控制器上,并延续原断点处继续工作,实现了无缝连接。3.根据工艺要求,设计了连续燃烧的控制系统(CCS),包括负荷控制、蒸汽压力控制、风燃比控制以及雾化蒸汽压力控制等。4.为了实现燃油燃气燃烧器的配比计算、掺烧、热态切换,文章引入标准燃料量的概念。以某种燃料量作为标准燃料量,其他燃料则根据标准燃料热值对比,对其进行运算转换。即进入系统的所有燃料量均转换成标准燃料量,将标准燃料量总和看作进入燃烧器一种燃料的燃料量。经过热态试验,任何一种燃料无论在单烧还是混烧情况下,通过标准燃料与送风的函数计算,都能得到合理的风燃比曲线,从而使燃烧器保持高效稳定的运行。更多还原

【Abstract】 With the rapid development of modern industrial technology, the ratio of energy utilization has to meet more strict demands. As the key equipment to convert primary energy resources to secondary energy resources, the boiler develops with increasing control and management level. The burner, the essential and most energy-consuming part of boiler, requires an advanced burning control system to operate effectively at the optimized air-fuel ratio, so as to save the energy and protect the environment. This article, with the subject of burning control for five 75t/h gas/oil boilers used in the power station provided by some refining company, and with the efforts to improve the control method for the burner made by my company on the basis of current burning control theory study, provides with the control method for multi-fuel mixed burning, and the software and hardware platform for burning control system based on SIEMENS S7-300 PLC software redundant system. This article contains researches from the following four aspects: 1. The burning management system ( BMS ) based on SIEMENS S7-300PLC software redundant system has been worked out. The BMS, composed of redundant system, flame detecting system and ignition system, is mainly responsible for ignition, purge, flame detection, main fuel Valve ON/OFF, fuel switching management, and the detection and security for fault switching value, such as fuel oil pressure, fuel gas pressure, etc.2. In accordance with the project requirements,the design introduces a redundant hot standby control. In the event of controller or power failure, the system can automatically switch to the alternate controller,resume work from the breakpoint,achieve the seamless connection.3. According to the technological requirements, the controlled combustion system (CCS), has been designed out. It includes load control, steam pressure control, air-fuel ratio control and atomizing steam pressure control, etc.4. In order to achieve the ratio of air-fuel burner calculation, mixed burning, thermal switch, the article introduces the concept of the standard fuel quantity. We can set the quantity of a certain fuel as the standard, then compare the heating values of other fuels with that of the standard fuel, and make final calculations. In this way, the total quantity of the fuels coming into the system is converted into standard fuel quantity, and the total standard fuel quantity can be regarded as the quantity for only one fuel. The thermal test has proved that, by means of the curves for both standard fuel conversion and standard fuel-to-air ratio, either single-fuel burning or multi-fuel mixed burning, can achieve reasonable air-fuel ratio, which finally enables the boilers to work effectively and stably.更多还原