应用于机炉协调控制的能量平衡与主汽压力调节相结合的控制策略

对锅炉、汽轮机的动态特性及直接能量平衡(DEB)控制策略、能量平衡信号和主汽压调节进行了分析研究，设计了有效实用的机炉协调控制系统，并在实际工程中应用。该系统不仅改善了机炉被调量的调节品质，提高了协调控制系统适应负荷变动的能力，而且减少了现场调试的工作量。     

电厂锅炉燃烧控制系统优化

结合南京热电厂6号锅炉燃烧控制系统的实际工程,分析基于直接能量平衡（DEB）压力控制系统的实质,提出分析、整定DEB系统的方法;同时还分析送、引风控制系统特点,提出优化送、引风控制系统方法。该优化控制技术已应用于南京热电厂6号锅炉燃烧控制系统中,明显改善了锅炉燃烧控制系统品质。     

改进型DEB协调控制在大迟延控制对象上的应用

针对神华陕西国华锦界能源有限责任公司(锦界电厂)3号亚临界600MW机组燃料量对主蒸汽压力变化响应的纯迟延长、惯性大的特点,将原机组协调控制系统的单纯直接指令平衡(DIB)控制系统前馈-反馈调节结构优化为改进型直接能量平衡(DEB)控制系统+动态预超调燃料前馈控制结构。应用结果表明,改进后的协调控制系统克服了机组的大迟延环节对主蒸汽压力调节的影响。当机组负荷指令变化时,控制系统快速改变汽轮机调节阀开度,从而消除或减小了锅炉主控对负荷变化响应的迟延;通过合理配置较大比例的动态预超调燃料前馈量,及时提高锅炉蓄热量,减小了主蒸汽压力的动态偏差。DEB控制系统在主蒸汽压力变化前通过锅炉热量信号动态预调节燃料量,使主蒸汽压力快速跟踪其设定值,对长迟延、大惯性系统具有较好的适应性。     

国内科技信息

DEB 协调控制系统在125MW 机组上的应用闵行发电厂11号机组协调控制系统采用 DEB 直接能量平衡控制方式。汽机侧控制汽机同步器采用高精度位置反馈装置和脉冲调节器加固态继电器输出的控制方式,大大提高了控制性能;锅炉侧控制燃烧系统在热负荷、送引风等多执行部件系统中采用了 MOCS系统,很好地解决了多执行机构的跟踪、增益自动修正及迅速克服内扰等问题;在送风的风量测量上采用了双文丘里测风装置,性能稳定可靠,维护量小;在引风调节系统中采用了非线性组件,克服了波动信号的干扰。整个协调控制系统具有完善的连续调节,逻     

国产燃煤直流单元机组的协调控制

本文所介绍的协调自动控制系统是以扰动量为粗调(前馈),以被调量为细调(反馈),即所谓前馈—反馈自动调节系统。根据直流锅炉的结构和运行上的特点,为了使机组能尽快地适应负荷变化的需要,能维持主蒸汽压力和温度在额定范围,又能安全经济运行,不仅燃烧率和给水要协调控制,而且锅炉、汽机和发电机也要协调动作。按直接能量平衡协调控制风、煤、水与外界负荷之间随时保持适当的比例。根据功率偏差,主蒸汽压力偏差和频率偏差信号控制主蒸汽调节门,与外界负荷保持适当的比例。调节与扰动几乎是同时进行的,这样被调量出现的偏差较小,再用被调量的偏差进一步校正。这种协调自控系统充分利用锅炉蓄热及时消除扰动,又能维持被调参数为额定值,动态偏差很小。     

直接能量平衡协调控制系统在600MW机组的应用

直接能量平衡(DEB)协调控制系统在工程领域得到了广泛的应用,介绍DEB协调控制系统的结构、基本原理和主要特性。DEB协调控制在神华陕西国华锦界能源有限责任公司的应用取得了良好的控制效果,阐述了在国华锦能公司协调控制系统的实施情况和改进效果。     

直接能量平衡协调控制系统特性分析

直接能量平衡(Direct Energy Balance,DEB)协调控制系统在工程领域得到了广泛的应用。本文对直接能量平衡协调控制系统进行了简单分析,并在Simulink平台上针对某600MW机组建立了DEB协调控制系统仿真模型,对仿真结果进行了分析。     

循环流化床机组一次调频功能的优化

1 循环流化床机组协调控制系统国华宁东电厂一期2×330 MW机组配置循环流化床(CFB)锅炉,机组控制系统采用杭州和利时有限公司生产的MACSV DCS,为DCS、数字式电液控制系统(DEH)一体化设计,协调控制系统采用直接能力平衡(DEB)协调控制方式,在协调控制策略中采用了机组能量平衡的自解耦控制,从而自动补偿机组滑压变负荷中锅炉蓄热、负荷斜坡变化调节器的静差,其主要包括指令运算回路、锅炉主控、汽轮机主控、负荷和压力设定、协调方式切换、一次调频等,主要信号有机组负荷、调节级压力p1、主蒸汽压力PT和汽包压力Pb,协调控制调节器输出锅炉燃料量和汽轮机调节阀开度指令.     

DEB协调控制策略在火电厂的应用

在大型火力发电厂中，自动控制系统中最高级别的协调控制系统的优良投入直接代表了机组的自动化水平。阐述了火力发电厂协调控制系统的控制原理和基本策略，介绍了目前世界范围内应用比较广泛的DEB(直接能量平衡)协调控制系统的原理和特点。DEB协调控制在江西丰城电厂的应用取得了良好的控制效果，介绍了在丰城电厂协调控制系统的相关运行方式和改进效果。     

采用辐射能反馈信号的火电单元机组负荷控制系统仿真研究

针对目前单元机组承担调峰任务,负荷增减频繁的现象,引入锅炉炉膛辐射能信号作为中间被调量,对锅炉燃烧率进行反馈控制,构成新的单元机组负荷协调控制方式。仿真研究结果表明,该控制系统能够提高机组负荷的跟踪性能,有效地克服锅炉燃烧率内对机组运行的影响,显著提高了系统的控制品质,并易于工程实现。     

新型均衡燃烧控制系统的设计及应用研究

传统的燃烧控制系统（ＴＣＣＳ）仅能控制进入锅炉炉膛的燃料总量,以适应机组的负荷变化,但不能保证进入炉膛的各个燃烧器的煤粉流量相等,这对于发电机组的安全性和经济性都会产生消极的影响。均衡燃烧控制系统（ＢＣＣＳ）的研究和开发正是为了解决上述问题。文中探讨了ＢＣＣＳ设计及实践中的若干理论和关键技术问题。目前,ＢＣＣＳ已成功用于２００ＭＷ机组,并获得了良好的运行效果。     

超超临界机组燃烧及水煤比控制策略研究与应用

通过分析燃烧主控的原理以及燃料指令的来源,对1 000 MW超超临界机组的燃烧控制策略进行研究,指出超超临界机组直流锅炉调节的关键是控制汽水分离器出口过热度,保证合适的水煤比。广东大唐潮州发电有限责任公司辅机故障减负荷(runback,RB)试验结果表明,在机组发生RB时水煤比控制是整个协调控制的关键。     

发电厂燃煤锅炉热效率在线监测技术与应用

从燃料燃烧的能量转换和守恒原理出发 ,对锅炉燃烧自动控制和锅炉热效率在线监测进行研究。用火焰参数代表燃料发热量信号和在线热效率信号 ,在不需要对风量和燃料精确测量的情况下 ,成功投入了燃烧自动控制系统 ,将锅炉热效率控制在最佳值 ,实现对锅炉热效率的实时在线监测。     

Study of connected system of automatic control of load and operation efficiency of a steam boiler with extremal controller on a simulation model

The problems of operation effectiveness increase of steam boilers are considered. To maintain the optimum fuel combustion modes, it is proposed to use an extremal controller (EC) determining the value of airflow rate, at which the boiler generating the desired amount of heat will consume a minimum amount of fuel. EC sets the determined value of airflow rate to airflow rate controller (ARC). The test results of numerical simulation dynamic nonlinear model of steam boiler with the connected system of automatic control of load and combustion efficiency using EC are presented. The model is created in the Simulink modeling package of MATLAB software and can be used to optimize the combustion modes. Based on the modeling results, the conclusion was drawn about the possibility in principle of simultaneously boiler load control and optimizing by EC the combustion modes when changing the fuel combustion heat and the boiler characteristics and its operating mode. It is shown that it is possible to automatically control the operation efficiency of steam boilers when using EC without applying the standard flue gas analyzers. The article considers the numerical simulation dynamic model of steam boiler with the schemes of control of fuel consumption and airflow rate, the steam pressure and EC; the purpose of using EC in the scheme with linear controllers and the requirements to the quality of its operation; the results of operation of boiler control schemes without EC with estimation of influence of roughness of thermal mode maps on the nature of static and dynamic connection of the control units of fuel consumption and airflow rate; the phase trajectories and the diagrams of transient processes occurring in the control scheme with EC with stepped changing the fuel quality and boiler characteristics; analysis of modeling results and prospects for using EC in the control schemes of boilers.     

一种非线性微分在协调控制系统中的应用

实际微分环节可以由一减一阶惯性环节构成,用速率限制非线性环节替代一阶惯性环节后,可得到一种非线性微分的描述函数,这种非线性微分的响应时间和微分作用随着输入信号幅值增加而增加。针对一典型300 MW机组协调控制系统,利用此非线性微分替代锅炉侧PID主控制器和负荷指令前馈中的微分环节,调试参数并仿真。实验结果表明：采用非线性微分的协调控制系统,在AGC指令大幅度变化时,微分作用较强,锅炉燃料量能够迅速变化从而保证机前压力稳定;在AGC指令小幅度变化时,微分作用减弱,能够有效减弱锅炉燃料量的波动幅度并维持机前压力在允许范围内。这种协调控制系统适合应用于电网AGC指令小幅度、高速率频繁变化的火电机组。     

循环流化床锅炉燃油系统节能技术探讨

循环流化床技术是一项新型环保技术，它在燃烧方式上与煤粉炉有本质区别，针对循环流化床锅炉运行特点，提出其燃油系统可实现间断运行的新思路．并据此运行方式绐出燃油系统供油泵选型的基本方法可使燃油系统节约大量电能.     

Experience Gained from Construction of Low-Emission Combustion Chambers for On-Land Large-Capacity Gas-Turbine Units: GT24/26

This article is the third in a planned series of articles devoted to the experience gained around the world in constructing low-emission combustion chambers for on-land large-capacity (above 250 MW) gas-turbine units (GTUs). The aim of this study is to generalize and analyze the ways in which different designers apply the fuel flow and combustion arrangement principles and the fuel feed control methods. The considered here GT24 and GT26 (GT24/26) gas-turbine units generating electric power at the 60 and 50 Hz frequencies, respectively, are fitted with burners of identical designs. Designed by ABB, these GTUs were previously manufactured by Alstom, and now they are produced by Ansaldo Energia. The efficiency of these GTUs reaches 41% at the 354 MW power output during operation in the simple cycle and 60.5% at the 505MW power output during operation in the combined cycle. Both GTUs comply with all requirements for harmful emissions. The compression ratio is equal to 35. In this article, a system is considered for two-stage fuel combustion in two sequentially arranged low-emission combustion chambers, one of which is placed upstream of the high-pressure turbine (CC1) and the other upstream of the low-pressure turbine (CC2). The article places the main focus on the CC2, which operates with a decreased content of oxygen in the oxidizer supplied to the burner inlets. The original designs of vortex generators and nozzles placed in the flow of hot combustion products going out from the high-pressure turbine are described in detail. The article also presents an original CC2 front plate cooling system, due to which a significantly smaller amount of air fed for cooling has been reached. The article also presents the pressure damping devices incorporated in the chamber, the use of which made it possible to obtain a significantly wider range of CC loads at which its low-emission operation is ensured. The fuel feed adjustment principles and the combustion control methods implemented in the low-emission combustion chambers of this GTU are of interest from the scientific and practical points of view.     

Studying the Aerodynamics of the TPP-210A Boiler Furnace When It Is Shifted to Operate with Dry-Ash Removal and Vortex Fuel Combustion

To reduce the amount of nitrogen oxide emissions and achieve more reliable operation of the TPP-210A boiler, a process arrangement for firing Grade TR Kuznetsk coal that involves using straight-flow burners and shifting the boiler from slag-tap to dry-ash removal is developed. Owing to a large burner downward slope angle and special arrangement of burners and nozzles, four large vertical vortices rotating in opposite directions are produced in the furnace lower part, as a result of which the combustion products dwell for a longer period of time in the burning zone and more complete fuel combustion is achieved. For verifying the operability and efficiency of the proposed combustion arrangement, investigations on a boiler furnace physical model were carried out using a technique for visualizing fuel jets and secondary and tertiary overfire air jets. The fuel jet temperature boundaries in the course of jet propagation in the furnace model are also determined. The study results have shown that staged fuel combustion will be set up with using the proposed arrangement of burners and nozzles. In addition, large vertical vortices produced in the furnace lower part will help to achieve more efficient use of the dry bottom hopper heating surfaces, due to which lower coal combustion product temperature in the furnace upper part and smaller content of combustible products in fly ash will be obtained. Owing to low values of air excess factor at the pulverized coal burner outlet and gradual admission of air into the vortex zone through a few nozzles with intense inner recirculation of combustion products to the jet initial section, staged combustion of pulverized coal and low nitrogen oxide emissions will be secured. Owing to expansion of fuel jets, a rapid growth of mass in the fuel jet is achieved, which is obtained both due to ejection of the jet itself and due to forced admission of hot fuel gases from other jets. Investigations carried out on the physical model have confirmed that the proposed combustion arrangement features high efficiency and that a low content of nitrogen oxides in flue gases is obtained.     

“W”型火焰锅炉卫燃带改造

由于煤质变差,某360 MW机组“W”型火焰锅炉燃烧不稳,需大量投油助燃.对此,进行卫燃带改造.改造后,燃烧工况明显改善,火焰稳定性提高;助燃油投入量减少,机组负荷在200MW左右可不投油助燃;锅炉排烟温度由170～180℃降至150～160℃,大渣和飞灰含碳量降低.     

炉内燃烧三维可视化诊断及机组负荷控制新技术

介绍了一种基于炉内燃烧三维温度场可视化的监测方案。通过三维温度场所获得的总辐射能，建立辐射能信号与机组负荷之间能量平衡的新的协调控制模型，可更好地实现锅炉燃烧优化控制，提高机组负荷控制水平。