Boiler-turbine control system design using continuous-time nonlinear model predictive control

A continuous-time nonlinear model predictive controller(NMPC) was designed for a boiler-turbine unit.The controller was designed by optimizing a receding-horizon performance index,with the nonlinear system approximated by its Taylor series expansion with a certain order,the magnitude saturation constraints on the inputs satisfied by increasing the predictive time,and the rate saturation conditions on the actuators satisfied by tuning the time constant of the reference trajectories in a reference governor.Simulation results showed that the controller can drive the drum pressure and output power of the nonlinear boiler-turbine unit to follow their respective reference trajectories throughout a varying operation range and keep the water level deviation within tolerances.Comparison of the NMPC scheme with the generic model control(GMC) scheme indicated that the responses are slower and there are more oscillations in the responses of the water level,fuel flow input and feed water flow input in the GMC scheme when the boiler-turbine unit is operating over a wide range.

Tuning of Coordinated Controllers for Boiler-turbine Units

A simple two-by-two model for a boiler-turbine unit is derived in this paper, which can capture the essential dynamics of the typical process. The coordinated controller is designed based on this model. A PID control structure and a tuning procedure are proposed. The example shows that the method is easy to use and can achieve an acceptable performance.

Nonlinear inversion-based output tracking control of a boiler-turbine unit

The capability to perform fast load-following has been an important issue in the power industry. An output tracking control system of a boiler-turbine unit is developed. The system is composed of stable inversion and feedback controller. The stable inversion is implemented as a feedforward controller to improve the load-following capability, and the feedback controller is utilized to guarantee the stability and robustness of the whole system. Loop-shaping H∞ method is used to design the feedback controller and the final controller is reduced to a multivariable PI form. The output tracking control system takes account of the multivariable, nonlinear and coupling behavior of boiler-turbine system, and the simulation tests show that the control system works well and can be widely applied.

Study on Fuzzy Self-Adaptive PID Control System of Biomass Boiler Drum Water

The paper discusses the features of the Biomass Boiler drum water level. Conventional PID Control System can not reach a satisfaction result in nonlinearity and time different from Biomass Boiler Drum Water Control System. In this study, a kind of fuzzy self-adaptive PID controller is described and this controller is used in biomass boiler’s drum water level control system. Using the simulink tool of MATLAB simulation software to simulate the fuzzy adaptive PID and conventional PID control system, the result of the comparison shows that the fuzzy self-adaptive PID has the strong anti-jamming, flexibility and adaptability as well as the higher control precision in Biomass Boiler Drum Water.

Coordinated Controller Tuning of a Boiler Turbine Unit with New Binary Particle Swarm Optimization Algorithm

Coordinated controller tuning of the boiler turbine unit is a challenging task due to the nonlinear and coupling characteristics of the system.In this paper,a new variant of binary particle swarm optimization （PSO） algorithm,called probability based binary PSO （PBPSO）,is presented to tune the parameters of a coordinated controller.The simulation results show that PBPSO can effectively optimize the control parameters and achieves better control performance than those based on standard discrete binary PSO,modified binary PSO,and standard continuous PSO.

Simulation on an optimal combustion control strategy for 3-D temperature distributions in tangentially pc-fired utility boiler furnaces

The control of 3-D temperature distribution in a utility boiler furnace is essential for the safe, economic and clean operation of pc-fired furnace with multi-burner system. The development of the visualization of 3-D temperature distributions in pc-fired furnaces makes it possible for a new combustion control strategy directly with the furnace temperature as its goal to improve the control quality for the combustion processes. Studied in this paper is such a new strategy that the whole furnace is divided into several parts in the vertical direction, and the average temperature and its bias from the center in every cross section can be extracted from the visualization results of the 3-D temperature distributions. In the simulation stage, a computational fluid dynamics(CFD) code served to calculate the 3-D temperature distributions in a furnace, then a linear model was set up to relate the features of the temperature distributions with the input of the combustion processes, such as the flow rates of fuel and air fed into the furnaces through all the burners. The adaptive genetic algorithm was adopted to find the optimal combination of the whole input parameters which ensure to form an optimal 3-D temperature field in the furnace desired for the operation of boiler. Simulation results showed that the strategy could soon find the factors making the temperature distribution apart from the optimal state and give correct adjusting suggestions.

A mathematical model for optimized operation and controlin a CDQ-Boiler system

Based on analyzing the thermal process of a CDQ （coke dry quenching）-Boiler system, the mathematical model for opti-mized operation and control in the CDQ-Boiler system was developed. It includes a mathematical model for heat transferring process in the CDQ unit, a mathematical model for heat transferring process in the boiler and a combustion model for circulating gas in the CDQ-Boiler system. The model was verified by field data, then a series of simulations under several typical operating conditions of CDQ-Boiler were carried on, and in turn, the online relation formulas between the productivity and the optimal circulating gas, and the one between the productivity and the optimal second air, were achieved respectively. These relation equations have been success- fully used in a CDQ-Boiler computer control system in the Baosteel, to realize online optimized guide and control, and meanwhile high efficiency in the CDQ-Boiler system has been achieved.

The Development and Research on the Coordinate Control Strategy Between Turbine and Boiler in Fossil Power Plant

Based on the research on domestic and international automatic technical development in fossil power plant,the paper analyses the recent situation of the coordinate control system between turbine and boiler of domestic fossil Power Plant,provides the development thought of coordinate control system between turbine and boiler,and describes the application prospect in control system of fossil power plant combining with the application experience.

酒糟锅炉周期性冒黑烟的原因分析及控制研究

针对酒糟锅炉在调试过程中出现的烟囱周期性冒黑烟问题,首先对锅炉燃料成分、酒糟燃烧特性、锅炉结构、锅炉燃烧方式及烟气流程进行了介绍;然后分析了黑烟的产生及危害;紧接着分析了锅炉烟囱周期性冒黑烟的原因,并在此基础上对螺旋给料机进行了改造,对湿式除尘器进行了更换;最后经过效果检查,锅炉烟囱周期性冒黑烟的问题得到了有效解决,这为类似锅炉技术改造提供了参考。

基于炉膛气氛场的锅炉燃烧区域风量调节与控制技术及应用

讨论了锅炉风量控制的重要性,阐述了常规锅炉风量控制技术的现状,提出了基于炉膛气氛场的燃烧区域局部风量调节与控制技术,并重点介绍了该技术中CO及H2S测量等炉膛气氛场测量技术以及风量控制原理。介绍了在某600MW火电机组上的应用情况,并进行了经济性分析。结果表明,该技术能有效减少锅炉的化学不完全燃烧和机械不完全燃烧损失,避免非停损失和爆管维修损失,具有较好的经济性。

改进自适应遗传算法优化的船用增压锅炉上锅筒水位滑模控制方法

[目的]船用增压锅炉的上锅筒水位由于航行中负荷的频繁变化,难以获得理想的控制效果。为了保证上锅筒水位的稳定,对大负荷扰动下的上锅筒水位控制方法进行研究。提出一种基于改进自适应遗传算法优化的增压锅炉上锅筒水位滑模控制方法。[方法]将上锅筒水位偏差的速度和速度变化率引入S函数来设计滑模控制器,采用李雅普诺夫稳定性原理证明其稳定性。在此基础上,利用改进的自适应遗传算法优化滑模控制器。[结果]将改进的自适应遗传算法优化的增压锅炉上锅筒水位滑模控制方法与传统的PID控制方法进行了对比分析。在响应斜坡扰动信号和阶跃扰动信号时,改进自适应遗传算法优化的滑模控制器均能够无差跟踪输入信号,其稳定时间比PID缩短5 s,超调量也小于PID。[结论]仿真结果表明,改进自适应遗传算法优化的滑模控制方法具有更优的控制效果。

基于ASME标准制造的黑液锅炉部件质量管控措施

本文通过对出口海外、按ASME标准规范设计、制造的黑液锅炉部件质量控制技术进行研究,识别分析在设计、制造上的质量风险点,并结合制造经验进行对策实施,为后续类似产品的生产做好技术总结和借鉴参考。

ControlLogix在扩建电厂锅炉补给水控制系统中的应用

针对因电厂扩建,原锅炉补给水控制系统不能满足需求,对锅炉补给水控制系统进行了改造。详细介绍了控制系统的设计和功能。

发电厂集控运行中的节能措施分析

阐述发电厂集控运行的节能降耗问题及原因,提出一系列解决措施,包括加强锅炉控制、确保汽轮机组高效运行、降低电厂整体用电、优化电厂生产管理。这些措施能够减少能源浪费和环境污染,提高企业的竞争力。

Controller Link网络在工业控制系统中的应用

介绍了欧姆龙Controlnet总线系统的特点以及在工业现场的应用。分析了传统的工业现场控制中存在的诸多缺点 ,并给出了实例 ,用它实现电厂锅炉自动点火、锅炉保护。

融合激光雷达料位测算的锅炉燃烧优化模型预测控制

提出了一种融合激光雷达料位测算的锅炉燃烧优化控制策略。该控制策略通过激光雷达对生物质的入炉给料量进行实时在线监测,并采用最大互信息系数(MIC)方法分析其对于主汽压力、燃烧室温度、出口烟气氧量等关键参数的时延长度,结合经过特征筛选的锅炉特征参数,构成模型样本集;通过粒子群优化(PSO)算法进行参数优化,获得燃烧过程外源自回归(ARX)模型,并采用模型预测控制的方法优化锅炉燃烧。以700t/d生物质燃烧发电锅炉为测试对象,该控制策略在主汽压力与燃烧室温度约束下实现了烟气氧量优化。实验结果与对比分析表明:(1)该预测模型具有较高的精度与泛用性,能满足预测控制的要求;(2)相较于PID与模糊控制,该控制算法拥有更高的控制性能,在仿真结果中氧量与其设定值的平均偏移能控制在±25%以内。该控制策略理论上具有较好的实践意义,可为生物质发电锅炉的智能化稳定燃烧提供解决方案。

烧结余热锅炉水位模糊控制设计研究

本文主要探究了烧结余热锅炉的水位模糊控制设计要点,并设计仿真实验对比验证了不同控制器的水位调控效果。水位模糊控制系统由知识库和模糊控制器两部分组成,以水位和蒸发量为输入,以控制量为输出。在设计模糊集与模糊控制规则的基础上,建立了13×13的模糊矩阵作为锅炉水位模糊控制查询表,系统将模糊量化处理结果对照查询表后得到输出值,完成水位控制。仿真实验表明,PID控制的水位控制精度较高,响应速度慢、超调量大;模糊控制的响应速度快,超调量小,存在稳态静差;混合型模糊PID控制将两者优势结合,使锅炉水位控制的速度更快、超调量更小且消除稳态静差,水位控制效果更好。

火电机组脱硝改造后的控制优化

本文对火电机组进行脱硝改造后的控制关键技术,主要包括二次风系统控制策略完善、燃烧系统整体控制策略完善、供热控制方式的控制完善等进行了总结,同时,针对脱硝系统对机组协调控制的影响,本文提出了对锅炉主控、煤质校正、汽轮机主控、变负荷前馈控制、送风及引风控制、一次风控制、磨煤机冷热风挡板控制等主要控制回路的优化措施。

先进控制在燃气锅炉自动变负荷中的应用

钢厂燃气锅炉装置的燃气压力变化幅度较大,导致锅炉装置频繁进行变负荷操作,若依靠人工调节,则存在燃烧不充分、劳动强度大、燃气放散等问题。为了解决这些问题,设计并采用了APC-Suite先进控制软件,在自动变负荷过程中建立了燃气锅炉的先进控制系统。系统实施后,不仅保证了自动变负荷的平稳进行,还实现了燃烧优化,提升了装置的平稳性和自动化程度。