检索结果-内蒙古大学图书馆

Reduction of the Optimization Efforts with Predictive control by Using Non-Equidistant Prediction Points

IFAC Proceedings Volumes 2003年第8期36卷 57-62页

作者： U. Schmitz R. Haber R. Bars Department of Plant and Process Engineering Laboratory of Process Control University of Applied Science Cologne D-50619 Köln Betzdorf er Str. 2 Germany fax: +49-221-8275-2836 Department of Automation and Applied Informatics MTA-BME Control Research Group Budapest University of Technology and Economics Hungary

With predictive control most of the computation time is spent for the simulation of the predicted variables and for the optimization if constraints or nonlinear processes are assumed. In addition to the known blocking technique for the manipulated variable another possibility is calculating the control error not in each sampling point of the prediction horizon but only in some coincidence points. It will be shown that the best choice is to allocate the coincidence points exponentially thus that with small prediction steps more and with increasing prediction steps less coincidence points are considered. As a practical example the multivariable control of a distillation column model illustrates the benefits of the method presented.

关键词： Predictive control optimal control control applications chemical industry execution time

来源：评论

学校读者我要写书评

暂无评论

Long-range optimal model and multi-step-ahead prediction identification for predictive control

引用

IFAC Proceedings Volumes 2003年第16期36卷 477-482页

作者： R. Haber U. Schmitz R. Bars Department of Plant and Process Engineering Laboratory of Process Control University of Applied Science Cologne D-50679 Köln Betzdorfer Str. 2 Germany fax: +49-221-8275-2836 Department of Automation and Applied Informatics Control Research Group of the Hungarian Academy of Sciences Budapest University of Technology and Economics Hungary

Long-range optimal prediction algorithms use the predicted output for several steps ahead. The prediction based on traditionally estimated model parameters does not result in an optimal prediction if the measurements are noisy or/and model structure differs from real process structure. In this paper two different identification schemes are presented and compared: long-range predictive single-model identification and simultaneous multi-step-ahead prediction identification. It is shown that the first method is easier to realize but the second one leads to more accurate results. Both methods are derived for a first-order model in details. Simulation runs and a level control example illustrate the algorithms presented.

关键词： process identification prediction parameter estimation predictive control

来源：评论

学校读者我要写书评

暂无评论

An infeasibility degree selection based genetic algorithms for constrained optimization problems

An infeasibility degree selection based genetic algorithms f...

引用

System Security and Assurance

作者： Mu, Sheng-Jing Su, Hong-Ye Chu, Jian Wang, Yue-Xuan Natl. Lab. of Indust. Cntr. Technol. Inst. of Adv. Process Control Zhejiang University Yuquan Campus Hangzhou 310027 China Natl. CIMS Engineering Res. Center Inst. of System Integration Department of Automation Beijing 100084 China

ISBN: (纸本)0780379527

In this paper, a genetic algorithm based on Infeasibility Degree (IFD) selection is proposed for constrained optimization problems. Initial solutions and intermediate solutions are allowed to be feasible as well as infeasible as penalty function methods. The infeasibility degree of a solution (IFD) is defined as the sum of the square value of all the constraints violation and the infeasibility degree selection of the population is designed through checking whether the IFD of a solution is less than or equal to a threshold value or not to decide the candidate solution is acceptable or refusable. The method is divided into two stages: first, initial IFD selection is carried out to produce enough initial feasible solution;then the GAs based on Annealing IFD selection is applied to search for the feasible optimum solution. Two selected problems are used to test the algorithm performance.

关键词： control system analysis

来源：评论

学校读者我要写书评

暂无评论

An efficient information server for advanced plant asset management

An efficient information server for advanced plant asset man...

引用

International Conference on Emerging Technologies and Factory automation (ETFA)

作者： J. Muller U. Epple M. Wollschlaeger C. Diedrich Department of Process Control Engineering RWTH Aachen Aachen Germany Ifak-Institut für Automation und Kommunikation e.V. Magdeburg Barleben Germany

In already installed fieldbus instrumentations, a configuration-free and manufacturer-independent access to field device information sets is still missing. Due to the lack of suitable and simple models, as well as of interaction patterns of field devices in various information worlds of process control engineering, the practical use made of device novelties is rather complex. This affects high investments for engineering this information in various applications of process control engineering. Modern field devices contain embedded information sets that are ever-increasing, and provide great opportunity for innovative asset management functionality. In this paper we present an information server, serving as an additional information channel between field and plant level in process industry. We show that this so-called asset management box provides the configuration-free analysis of fieldbus segments, the open access to installed field devices and the automatically updated, structured and self-descriptive presentation of their embedded information sets. Its basic functionality fulfills one prerequisite of an efficient asset management system: the analysis of the actual state of a fieldbus installation, without prior knowledge about the installed field devices and enhanced investments in engineering. We discuss several asset management applications, implemented on the asset management box. To prevent excessive investments for engineering of asset management applications themselves, widest flexibility and extensibility of the management systems' functionality is required. The box's structure permits easy extensibility of plant and client-specific applications as well as the easy integration of specific fieldbus hardware, the box provides a universal fieldbus interface.

关键词： Asset management Field buses Investments process control Instruments Manufacturing Electrical equipment industry Information analysis Knowledge engineering engineering management

来源：评论

学校读者我要写书评

暂无评论

Optimal Choice of Horizons for Predictive control by Using Genetic Algorithms

引用

IFAC Proceedings Volumes 2003年第18期36卷 507-512页

作者： R. Haber U. Schmitz R. Bars Department of Plant and Process Engineering Laboratory of Process Control University of Applied Science Cologne D-50679 Köln Betzdorfer Str. 2 Germany fax: +49-221-8275-2836 Department of Automation and Applied Informatics Budapest University of Technology and Economics H-1111 Budapest Goldmann Gy. tér 3. Hungary fax : +36-1-463-2871

For predictive control in industry often very long horizons for control error and manipulated signal are used because of the slow processes which take place in the petrochemical industry. In order to reduce the computational effort some commercial predictive control program packages offer the ability to reduce the number of points in both horizons but do not recommend how to select the points which have to be considered in the horizon of the control error and manipulated variable. In this work the authors introduce an optimal choice not only of the horizon lengths itself but also for the strategy of reducing the number of points in the horizons. A genetic optimization algorithm was used both for the search for the optimal length of the horizons and for the best allocation of the points in the horizons. The results of the optimization process where used to deduct a simple rule.

关键词： Predictive control long horizons blocking coincidence points compaction points optimal choice of horizons

来源：评论

学校读者我要写书评

暂无评论

Hybrid IMC Dead-Beat controller Design in Delta Domain

引用

IFAC Proceedings Volumes 2003年第18期36卷 381-386页

作者： Zs. Preitl R. Bars I. Vajk R. Haber Department of Automation and Applied Informatics Budapest University of Technology and Economics. MTA-BME Control Research Group H-1111 Budapest Goldmann Gy. tér 3. Hungary: fax : + 36-1-463-2871 Department of Plant and Process Engineering University of Applied Science Cologne Germany

The paper presents a control system design technique in delta domain for IMC (Internal Model control) structure. Also a generalised form for delta domain Dead-beat control algorithm is given, a hybrid implementation of the controller (Z-domain combined with delta domain) is presented and its architecture is compared with the pure deltadomain implementation. The effect of placing the limitations in the IMC structure is also studied. The hybrid control structure is compared with a similar Dead-beat controller in Z-domain for second and third order plants (benchmarks). An illustrative sensitivity analysis between the hybrid control system and the Z-domain system has been performed.

关键词： controller design delta domain generalised hybrid Dead-beat controller sensitivity analysis

来源：评论

学校读者我要写书评

暂无评论

Nonlinear process Identification and Predictive control by the Weighted Sum of Multi-Model Outputs

引用

IFAC Proceedings Volumes 2003年第18期36卷 129-134页

作者： U. Schmitz R. Haber R. Bars Department of Plant and Process Engineering Laboratory of Process Control University of Applied Science Cologne D-50679 Köln Betzdorfer Str. 2 Germany fax: +49-221-8275-2836 Department of Automation and Applied Informatics Budapest University of Technology and Economics H-1111 Budapest Goldmann Gy. tér 3. Hungary fax : +36-1-463-287l

Most industrial processes are nonlinear. In such a case only a nonlinear model valid for the whole working area can ensure a good controller design. The nonlinear process is approximated by a multi-model consisting of the intelligent combination of some linear sub-models. As a very practical way the following identification strategy was used: independent model parameter estimation in the different working points and the calculation of the global valid model output as the weighted sum of the sub-models. As a weighting function the Gaussian function is used. The parameters of the Gaussian function were chosen either without or with optimization of the identification cost function. The global valid nonlinear model was used for model based predictive control. A heat exchanger example illustrates the method.

关键词： process identification nonlinear models predictive control multi-model heat exchanger

来源：评论

学校读者我要写书评

暂无评论

On the application of multimedia in control and automation

On the application of multimedia in control and automation

引用

IEEE International Caracas Conference on Devices, Circuits and Systems

作者： R. Moller Automation and Process Control Engineering Department of Electrical Engineering University of Wuppertal Germany

The degree of machine automation is continuously increasing, because computer technology, control software, telecommunication technology and visualization systems are also continuously improved. This makes the use of new multimedia techniques for reading, communication and presentation of machine or process data possible, even over far distances. Multimedia communication is becoming a technology of growing importance for user interfaces in automation and process control. Think of acoustic and visual data obtained from microphones or cameras applied to a certain automated system. They can be simply used and understood as a new brand of sensors or actuators that are part of a process control unit. Supervising and monitoring of certain process states is simplified, if the operator can "see" and "hear" the real process. Technical aspects concerning types, quality and speed of multimedia data communication will be discussed and especially viewed for an implementation in automated systems.

关键词： Automatic control automation Communication system control Telecommunication control Multimedia communication process control Application software Telecommunication computing control systems Data visualization

来源：评论

学校读者我要写书评

暂无评论

Optimal energy cost in ideal internal thermally coupled distillation columns

Optimal energy cost in ideal internal thermally coupled dist...

引用

American control Conference (ACC)

作者： Xinggao Liu Yongmao Xu Jie Zhang Jixin Qian Institute of Process Control Engineering Department of Automation Tsinghua University Beijing China Department of chemical and Process Engineering University of Newcastle Newcastle-upon-Tyne UK Institute of Industrial Process Control University of Zhejiang Hangzhou China

ISBN: (纸本)0780372980

Internal thermally coupled distillation column (ITCDIC) is the frontier of energy saving distillation research. In the paper, an evaluation method on operating cost and its saving in the ITCDIC processes of ideal mixtures is presented. A mathematical model for optimization is first derived. The benzene-toluene system is studied as an illustrative example. The optimization results show that the energy cost saving potential is close to 40% and annual energy cost saving is about 0.3 million dollars compared with the operating cost of a conventional distillation column operated at the minimum reflux ratio. The process analysis is also carried out. The optimal operating conditions and some useful results are obtained. These pave the way for the smooth operation and the further optimal design of ideal ITCDIC processes.

关键词： Cost function Distillation equipment Heat sinks Chemical industry process control Power engineering and energy Chemical processes Mathematical model Potential energy Temperature

来源：评论

学校读者我要写书评

暂无评论

controller performance assessment and monitoring - theory and its applications

Controller performance assessment and monitoring - theory an...

引用

World Congress on Intelligent control and automation (WCICA)

作者： Maying Yang Xiaoming Jin Automation Department Information engineering College Zhejiang University of Technology Hangzhou China Institute of Advanced Process Control University of Zhejiang Hangzhou China

controller performance assessment is a challenging task in industrial process control. In this work, we review the state of research in controller performance assessment and monitoring, and present some commercial implementations of the technology in process industries. Challenges related to the controller performance evaluation are outlined for research and applications.

关键词： Automatic control automation process control Educational institutions Industrial control Computerized monitoring Intelligent control

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：