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A mathematical model for optimized operation and controlin a CDQ-Boiler system 被引量:1
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作者 De Wang Tao Yang +4 位作者 Zhi Wen Junxiao Feng Ning Kong Qin Wang Weimin Wang 《Journal of University of Science and Technology Beijing》 CSCD 2005年第5期390-393,共4页
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 mode... 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. 展开更多
关键词 coke dry quenching-boiler system optimized operation and control mathematical model
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Mathematical model and magnetic-control mechanism of the stability of rotating spray transfer 被引量:14
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作者 殷树言 陈树君 +1 位作者 王军 徐鲁宁 《China Welding》 EI CAS 2003年第1期57-61,共5页
To realize stable rotating spray transfer in the region of high constant current is the key of realizing high deposition rate MAG welding process without helium in shielding gas and extending the welding current rang... To realize stable rotating spray transfer in the region of high constant current is the key of realizing high deposition rate MAG welding process without helium in shielding gas and extending the welding current range of traditional MAG welding process. In this paper, the magnetic control mechanism of the rotating spray transfer is stated and mathematical model is given. Theoretic basis is established, which implements high deposition rate MAG welding process with magnetic control instead of helium in shielding gas. 展开更多
关键词 magnetic control rotating spray transfer high deposition rates MAG welding process mathematical model
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Mathematical Model of Dynamic Operation and Optimum Control of Billet Reheating Furnace 被引量:1
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作者 刘日新 宁宝林 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1992年第4期279-283,共5页
This paper provides a mathematical model for the billet reheating process in furnace.A new optimum method is brought up that the objective function is the integral value of enthalpy increasing process of a billet.Diff... This paper provides a mathematical model for the billet reheating process in furnace.A new optimum method is brought up that the objective function is the integral value of enthalpy increasing process of a billet.Different delays are simulated and calculated,some proper delay strategies are ob- tained.The on-line computer control model is de- veloped.The real production conditions simulated, the temperature deviation of drop out billet from the target temperature is kept within±15℃. 展开更多
关键词 reheating furnace enthalpy increasing process delay strategy on-line computer control mathematical model
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Mathematical model of metallurgical thermal processes and application
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作者 WEN Zhi,DOU Ruifeng,SU Fuyong,LIU Xunliang and LOU Guofeng Department of Thermal Engineering,University of Science & Technology Beijing,Beijing 100083,China 《Baosteel Technical Research》 CAS 2010年第S1期100-,共1页
There are lots of physical changes and chemical reactions in the processes of iron and steel making, these processes are quite complex in the aspect of heat transfer.The processes of iron and steel making can be appro... There are lots of physical changes and chemical reactions in the processes of iron and steel making, these processes are quite complex in the aspect of heat transfer.The processes of iron and steel making can be approximately divided into three kinds.The first kinds are the processes of fusion metallurgy which involve enormous chemical reactions,such as blast furnace,converter,electric furnace and coke oven.The second kinds are the processes of heating and cooling which are mainly the physical changes,such as walking-beam reheating furnace,annular heating furnace and car-type furnace.The third kinds are the processes of heat treatment which mainly adjust metallurgical structure of metal,such as roller hearth heat treatment furnace, strip continuous heat treatment vertical/horizontal furnace and HPH bell-type annealing furnace.Every process can only be finished in particular thermal equipment.And all the physical and chemical processes mentioned above must obey first principles of engineering thermodynamics,heat & mass transfer,hydromechanics, combustion,metallurgy physical chemistry etc,and which can be summarized as principle of heat transfer,mass transfer,momentum transfer and chemistry reaction.In this paper,based on first principle of heat and mass transfer in iron and steel making processes,a series of mathematical models of thermal equipments and processes are presented.Such as the model of hot-blast stoves,coke oven,CDQ-boiler system,sintering, reheating furnace,soaking furnace,annular heating furnace,roller hearth heat treatment furnace,strip continuous heat treatment vertical/horizontal furnace,HPH bell-type annealing furnace,control cooling of medium plate,burner,heat exchanger and regenerative burner etc.The on-line application of the model is based on experimental certification of the mathematical model.And finally the computer optimization system of metallurgical thermal process is obtained. 展开更多
关键词 metallurgical thermal process mathematical model optimization and control
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Semantic model and optimization of creative processes at mathematical knowledge formation
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作者 Victor Egorovitch Firstov 《Natural Science》 2010年第8期915-922,共8页
The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the ... The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications. 展开更多
关键词 The Cybernetic Conception Optimization of control Quantitative And Qualitative Information Measures modelling Intellectual Systems Neural Network mathematicAL Education The control of Pedagogical processES CREATIVE Pedagogics Cognitive And CREATIVE processES Informal Axiomatic Thery SEMANTIC NET NET Optimization Parameters The Topology of SEMANTIC NET Metrization The System of Coverings Stochastic model of CREATIVE processES At The Formation of mathematicAL Knowledge Branching Markovian process Great Main Points Strategy (GMP-Strategy) of The CREATIVE processES control Interdisciplinary Learning: Colorimetric Barycenter
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DESIGN OF AN EXPERT CONTROL SYSTEM FOR LEACHING PROCESS 被引量:1
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作者 Wu, Min Peng, Zhihong +2 位作者 Gui, Weihua Nakano, Michio Jinhua, She 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第1期139-146,共8页
INTRODUCTIONThemainprocesesinzinchydrometalurgyareleaching,purificationandelectrolysis[1,2].Theleachinginvol... INTRODUCTIONThemainprocesesinzinchydrometalurgyareleaching,purificationandelectrolysis[1,2].Theleachinginvolvesdisolvingzinc?.. 展开更多
关键词 LEACHING process EXPERT control SYSTEM mathematical model rule model
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Numerical Controlled Rolling Process of Thick Metal Plate
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作者 LI Jia, YAN Xiang-an, WANG Guo-dong, JIA An-dong (School of Mechanical Engineering, Tianjin University, Tianjin 300072, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期22-23,共2页
Thick metal plate rolling process has become more and more important in building a flat roof of drilling on the bottom at sea. This is because not only the product quality requirement higher and higher but also the ma... Thick metal plate rolling process has become more and more important in building a flat roof of drilling on the bottom at sea. This is because not only the product quality requirement higher and higher but also the marketing competition. To improve the process of thick metal plate rolling and to increase productivity a numerical controlled rolling process is developed, which include the process planning, the mathematical model establishment and the numerical control system development. The process is for the 17 000 kN×3 000 mm movable up roller bending machine. According to the machine configuration non-symmetry rolling process is planed. This makes it possible to integrate all the steps of plate shaping up such as end side bending, several times of semi-shape bending and the last shape finishing. Since the process will perform under the numerical controlled condition whole steps of the process are considered can be worked in the automatic cycle. The mathematic model consists of two sections, the theory model and the experience parameters model. Which takes the original plate parameters such as geometry and mechanics, characters of the machine such as the movement limits, tonnage and so on as input and calculates all the parameters needed in process performing. Meanwhile, the mathematic Model is totally adapted to the control system. The numerical control system development scheme is based on all the works above. Here, a system plan is provided. The functional modules and hardware selection, in detail, are introduced. The system software on top level and the controlling software for controller are developed. And some unit techniques in the system such as timer setting, communication between system and controller, video integration, and the ability of resisting impact force are introduced. The process has been used successfully in production for more than two years. Practice approves that the process is robust. 展开更多
关键词 metal plate bending process planning numerical control system mathematical modelling
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膜洗滤过程数学建模与操作优化
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作者 杨维 陈丽红 +2 位作者 林先平 王岚 王龙耀 《化学反应工程与工艺》 CAS 2024年第3期274-281,共8页
膜洗滤过程包括浓缩环节和顶洗环节,并可简化为单一的浓缩或顶洗,是压力驱动型筛分截留膜分离过程的一种基本工艺模式。膜洗滤过程的模型化研究,涉及从微观渗透传递机理到宏观工艺过程的宽范围内容,存在变量多、形式复杂、求解困难等问... 膜洗滤过程包括浓缩环节和顶洗环节,并可简化为单一的浓缩或顶洗,是压力驱动型筛分截留膜分离过程的一种基本工艺模式。膜洗滤过程的模型化研究,涉及从微观渗透传递机理到宏观工艺过程的宽范围内容,存在变量多、形式复杂、求解困难等问题。本文在分析和总结膜洗滤过程的基础上,按照间歇顶洗和连续顶洗的类别,分别综述了膜洗滤过程的物料衡算模型和时间优化模型的相关研究,并对多参数协同优化的膜洗滤过程的模型化研究进行了展望。在应用过程中,系统性理论模型的支持,能够在有限的实验和定性判断基础上确定膜处理工艺和参数,这将为膜设备性能的发挥和生产效率的提高提供关键理论支撑。 展开更多
关键词 膜分离 洗滤 数学模拟 过程控制 优化设计
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Dynamic optimization of 1,3-propanediol fermentation process:A switched dynamical system approach 被引量:2
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作者 Xiang Wu Yuzhou Hou +1 位作者 Kanjian Zhang Ming Cheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第4期192-204,共13页
This paper considers a dynamic optimization problem(DOP)of 1,3-propanediol fermentation process(1,3-PFP).Our main contributions are as follows.Firstly,the DOP of 1,3-PFP is modeled as an optimal control problem of swi... This paper considers a dynamic optimization problem(DOP)of 1,3-propanediol fermentation process(1,3-PFP).Our main contributions are as follows.Firstly,the DOP of 1,3-PFP is modeled as an optimal control problem of switched dynamical systems.Unlike the existing switched dynamical system optimal control problem,the state-dependent switching method is applied to design the switching rule.Then,in order to obtain the numerical solution,by introducing a discrete-valued function and using a relaxation technique,this problem is transformed into a nonlinear parameter optimization problem(NPOP).Although the gradient-based algorithm is very efficient for solving NPOPs,the existing algorithm is always trapped in a local minimum for such problems with multiple local minima.Next,in order to overcome this challenge,a gradient-based random search algorithm(GRSA)is proposed based on an improved gradient-based algorithm(IGA)and a novel random search algorithm(NRSA),which cannot usually be trapped in a local minimum.The convergence results are also established,and show that the GRSA is globally convergent.Finally,a DOP of 1,3-PFP is provided to illustrate the effectiveness of the GRSA proposed by this paper. 展开更多
关键词 process control OPTIMIZATION mathematical modeling Switched system State-dependent switching Global optimization
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Simulation Modeling by Fuzzy Nets
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作者 Xingui, He 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第4期25-31,共7页
Fuzzy technology is a newly developed discipline based on fuzzy mathematics. In the recent years, it has been successfully applied into many areas, such as process control, diagnosis, evaluation, decision making and s... Fuzzy technology is a newly developed discipline based on fuzzy mathematics. In the recent years, it has been successfully applied into many areas, such as process control, diagnosis, evaluation, decision making and scheduling, especially in simulation where accurate mathematical models can not or very hard be established. In this paper, to meet the demands of fuzzy simulation, two fuzzy nets will first be presented, which are quite suitable for modeling the parallel or concurrent systems with fuzzy behavior. Then, a concept of active simulation will be introduced, in which the simulation model not only can show its fuzzy behavior, but also has a certain ability which can actively perform many very useful actions, such as automatic warning, realtime monitoring, simulation result checking, simulation model self-adapting, error recovery, simulating path tracing, system states inspecting and exception handling, by a unified approach while some specified events occur. The simulation model described by this powerful simulation modeling tool is concurrently driven by a network interpreter and an event monitor that all can be implemented by software or hardware. Besides, some interesting applications are given in the paper. 展开更多
关键词 Computer hardware Computer software Decision theory Fuzzy sets mathematical models MONITORING Parallel processing systems Petri nets process control Random processes SCHEDULING
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Computation Method for the Real-Time Control Problems in Differential-Algebraic Systems
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作者 Fei, Jinggao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第2期20-28,共9页
In this paper, a real-time computation method for the control problems in differential-algebraic systems is presented. The errors of the method are estimated, and the relation between the sampling stepsize and the con... In this paper, a real-time computation method for the control problems in differential-algebraic systems is presented. The errors of the method are estimated, and the relation between the sampling stepsize and the controlled errors is analyzed. The stability analysis is done for a model problem, and the stability region is ploted which gives the range of the sampling stepsizes with which the stability of control process is guaranteed. 展开更多
关键词 ALGEBRA Computational complexity Computer control systems Error analysis mathematical models process engineering Production engineering Real time systems Sampling System stability
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Optimization of Thermal Processes in Industrial Conditions
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作者 Rutkowki Alexandr Leonidovich Kovaleva Maria Alexandrovna Bilaonov Batraz Dydarovish 《Journal of Power and Energy Engineering》 2014年第9期81-85,共5页
On basis of the developed models of dependences of thermal processes, industrial conditions are received, having extreme character.
关键词 mathematicAL model OPTIMIZATION Dynamic CHARACTERISTIC STATIC CHARACTERISTIC process of BURNING System control of EXTREME
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History and General Characteristics of the Adaptive Control System of the Deuterium Pre-concentration Stage in Heavy Water Production
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作者 Karachenets Dmitryi 《Journal of Mathematics and System Science》 2019年第1期7-20,共14页
The history of creation in 1971–1975 years at SDB MMS of the Institute of Cybernetics (Kyiv city) the control system for the deuterium pre-concentration stage in heavy water production at Dneprodzerzhinsk chemical pl... The history of creation in 1971–1975 years at SDB MMS of the Institute of Cybernetics (Kyiv city) the control system for the deuterium pre-concentration stage in heavy water production at Dneprodzerzhinsk chemical plant (now Kamianske city, PJSC “DneprAzot”) is considered. It is given a technological block-diagram of the stage with its components and block-diagram of ACSTP which was developed in consequence of investigations of this complex managed object. A mathematical model of the distillation columns in the separating units of hydrogen isotopes which was used for synthesis of an algorithm of the adaptive stochastic optimal system with active accumulation of information about managed probabilistic processes is described. The results of the carried out tests of the system confirmed its efficiency. 展开更多
关键词 Adaptive control system DEUTERIUM HEAVY water DISTILLATION ACSTP mathematicAL model managed PROBABILISTIC process
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基于模拟退火的立式加工水基切削精度自适应控制
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作者 杨晓勇 《机械设计与制造工程》 2023年第9期55-58,共4页
为了提高立式加工水基切削控制精度,提出基于模拟退火的立式加工水基切削精度自适应控制方法。首先建立立式加工水基切削数学模型;其次设计了立式加工水基切削系统PID控制器;最后基于模拟退火方法对PID控制器进行参数优化,实现立式加工... 为了提高立式加工水基切削控制精度,提出基于模拟退火的立式加工水基切削精度自适应控制方法。首先建立立式加工水基切削数学模型;其次设计了立式加工水基切削系统PID控制器;最后基于模拟退火方法对PID控制器进行参数优化,实现立式加工水基切削精度的自适应控制。测试结果表明:所提方法在0.25 s即完成控制动态响应;在阻尼系数、转轴加速度、进给量发生改变时,仍能保持切削力稳定,鲁棒性较强;噪声干扰下切削力偏差值小于45.3 N,切削自适应控制精度较高。 展开更多
关键词 模拟退火 立式加工水基 切削精度自适应控制 PID控制器 切削数学模型
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石油钻机钻井中钻杆粘滑振动的建模和控制方法 被引量:1
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作者 尤立春 白德宇 +1 位作者 马志鑫 王录阳 《电气传动自动化》 2023年第4期1-6,共6页
石油钻机钻井作业过程中,由于强烈扭矩振动和井下摩阻所引起的钻杆粘滑振动现象不仅对作业效率有影响,还会带来钻杆钻头损伤问题,由此提出一种钻杆粘滑振动的建模及控制方法。将钻杆划分为较小扭矩部分,对整个系统进行动态建模,通过扭... 石油钻机钻井作业过程中,由于强烈扭矩振动和井下摩阻所引起的钻杆粘滑振动现象不仅对作业效率有影响,还会带来钻杆钻头损伤问题,由此提出一种钻杆粘滑振动的建模及控制方法。将钻杆划分为较小扭矩部分,对整个系统进行动态建模,通过扭矩模型和粘滑振动模型关联分析,为了减少控制过程的粘滑振动,提出转速控制、钻头重量控制和钻杆底部阻尼控制三部分,当钻杆长度划分为受力部分时,利用数学模型使得每种控制策略均对部分分析适用,而钻头重量控制与钻杆底部阻尼控制则采用两种控制方案。实验表明,该方法对底层钻井参数的控制要比表面参数控制更有效,可提高钻井作业效率、降低作业成本。 展开更多
关键词 粘滑振动数学模型 扭矩模型 钻井过程分解 粘滑振动控制
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玻纤织机收卷张力控制研究综述
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作者 胡晗 潘渡江 +2 位作者 徐君 潘石灵 龚小舟 《玻璃纤维》 CAS 2023年第5期35-41,45,共8页
归纳了近年来张力控制研究的关键问题,重点从收卷张力的研究、出现张力波动的原因、张力模型的建立等3个方面进行阐述,并介绍了影响因素及改善方法。并在此基础之上,对玻纤收卷张力的下一步研究方向提出了建议。该类织物在收卷过程中的... 归纳了近年来张力控制研究的关键问题,重点从收卷张力的研究、出现张力波动的原因、张力模型的建立等3个方面进行阐述,并介绍了影响因素及改善方法。并在此基础之上,对玻纤收卷张力的下一步研究方向提出了建议。该类织物在收卷过程中的张力控制尤为重要,并且因其强度高、不易腐蚀,而且耐磨性、耐高温,绝缘性较好,而得到广泛应用。 展开更多
关键词 玻纤 织机收卷工艺 张力控制 数学模型
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基于二维水流数学模型的江心洲防洪影响评价
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作者 王少冰 吕辉 韩会明 《水利建设与管理》 2023年第11期17-21,共5页
在赣江某江心洲保护利用工程中,为评价该工程对河道防洪安全的影响,采用二维水流数学模型对其兴建前后的河道水位、流速进行了计算和对比分析。结果表明,在河峰型洪水P=5%条件下,拟建工程附近水位变化幅度为-4~5cm;拟建工程对计算河段... 在赣江某江心洲保护利用工程中,为评价该工程对河道防洪安全的影响,采用二维水流数学模型对其兴建前后的河道水位、流速进行了计算和对比分析。结果表明,在河峰型洪水P=5%条件下,拟建工程附近水位变化幅度为-4~5cm;拟建工程对计算河段的整体流场影响不大,对江心洲岛上及左、右汊局部流场有一定的影响,流速变化幅度为-26.3~22.5cm/s。该江心洲保护利用工程对其所处河段行洪安全的不利影响较小。 展开更多
关键词 二维水流数学模型 防洪评价 江心洲 水位 流场
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锅炉受热面热力过程通用数学模型 被引量:11
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作者 王广军 李勇 +1 位作者 吴景兴 章臣樾 《中国电机工程学报》 EI CSCD 北大核心 1998年第4期254-257,共4页
建立了锅炉受热面热力过程通用数学模型。该模型的通用性包括三个方面:1)受热面动态计算与静态计算间的通用性;2)单相受热面与双相受热面间的通用性;3)模型在热力过程实时仿真及工程定量分析间的通用性。
关键词 锅炉 热力过程 数学模型 受热面 火力发电厂
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本生直流炉机炉协调控制系统的设计新方法及其工程应用 被引量:22
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作者 韩忠旭 齐小红 +4 位作者 潘钢 周广 相天成 刘丹 于光辉 《中国电机工程学报》 EI CSCD 北大核心 2005年第21期121-127,共7页
直流炉的控制技术是热控领域一个重要的研究课题,与汽包炉有较大的差别,该文从直流炉非线性数学模型的结构入手,导出其线性增量型数学模型,进而采用状态空间法加以描述,建立了相应的增量式状态观测器,分别设计了新型的适用于直流炉的机... 直流炉的控制技术是热控领域一个重要的研究课题,与汽包炉有较大的差别,该文从直流炉非线性数学模型的结构入手,导出其线性增量型数学模型,进而采用状态空间法加以描述,建立了相应的增量式状态观测器,分别设计了新型的适用于直流炉的机炉协调控制系统、锅炉给水控制系统和过热器蒸汽温度控制系统。通过在实践中对上述控制系统的整定与优化,取得了优良的控制效果:机组在大负荷范围(80MW)和高负荷变化速率(9MW/min)的工况下减负荷时,过热器出口汽温、机前压力和有功功率等参数的调节品质满足电力系统热工自动化的行业标准。现场实时控制的应用效果展示了该项技术的先进性和实用性,同时也为超临界机组控制策略的选择提供了参考和借鉴。 展开更多
关键词 直流炉 状态观测器 机炉协调控制系统 锅炉给水 非线性 数学模型 状态反馈控制
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分布式控制的直流微电网系统级稳定性分析 被引量:78
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作者 支娜 张辉 +1 位作者 肖曦 杨甲甲 《中国电机工程学报》 EI CSCD 北大核心 2016年第2期368-378,共11页
直流微电网以其可控性强和可靠性高等优点成为未来家庭和楼宇的主要供电架构,其系统级的稳定性研究是直流供电系统设计中的重要问题。通过建立直流微电网分布式控制策略下的统一数学模型,利用李雅普诺夫直接法研究直流微电网大信号稳定... 直流微电网以其可控性强和可靠性高等优点成为未来家庭和楼宇的主要供电架构,其系统级的稳定性研究是直流供电系统设计中的重要问题。通过建立直流微电网分布式控制策略下的统一数学模型,利用李雅普诺夫直接法研究直流微电网大信号稳定性的参数边界条件;通过分析电流小扰动对母线电压的影响,提出并联阻抗稳定性判定方法,为直流微电网系统级设计提供重要的参考依据。仿真结果表明,所提稳定性判定方法能够对直流微电网的稳定性进行判定。 展开更多
关键词 直流微电网 分布式控制 数学建模 系统级稳定性
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