检索结果-内蒙古大学图书馆

An approach to the direct analysis of transient stability

European Transactions on electrical Power 1993年第3期3卷 241-248页

作者： Djukanovic, M.B. Sobajic, D.J. Pao, Y.‐H. Miodrag B. Djukanovic (1959) received his B.S. M.Sc. and Ph.D. degrees in Electrical Engineering from the University of Belgrade/Yugoslavia in 1982 1985 and 1992 respectively specializing in electric power systems. In 1984 he joined the Electrical Engineering Institute “Nikola Tesla” in Belgrade where he was working on the scientific studies in the field of power systems planning operation and control. In 1985 and 1990 he was appointed as a research scholar at the Royal Institute of Technology Stockholm and Case Western Reserve University Cleveland Ohio. His major in- terests are in the area of power system analysis steady-state and dynamic security and application of neural networks in electric power systems. (Electrical Engineering Institute “Nicola Tesla” ul. Koste Glavinica 8A YU-11000 Belgrad T +3811/2351-619 Fax + 3811/2351-823) Dejan J. Sobajic (1949) received the B.S.E.E. and the M.S.E.E. degrees from the University of Belgrade/Yugoslavia in 1972 and 1976 respectively and the Ph.D. degree from Case Western Reserve University Cleveland Ohio in 1988. At present he is with the Department of Electrical Engineering and Applied Physics Case Western Reserve University Cleveland. He is also the Engineering Manager of A1 WARE Inc. Cleveland. His current research interests include power system operation and control neuralnet systems and adaptive control. He is a member of the IEEE Task Force on Neural-Network Applications in Power Systems and of the IEEE Intelligent Controls Committee. He is the Chairman of the International Neural-Networks Society Special Interest Group on Power Engineering. (Case Western Reserve University Department of Electrial Engineering and Computer Sciences Glennan Building Ohio 44 106 USA T + 1216/421-2380 Fax +1216/368-8776) Yoh-Han Pao (1922) has been a Professor of Electrical Engineering and Computer Science at Case Westem Reserve University (CWRU) Cleveland Ohio since 1967. He has served as chairman of the University's Electrical Engineering Department

The Transient Energy Function (TEF) method has been intensely investigated over the last decade as a reliable and accurate tool for transient stability assessment of multimachine power systems. In this paper we propose the Potential Energy Boundary Surface (PEBS) based method for direct analysis of transient stability. The critical value of transient energy and the Critical Clearing Time (T_CCT) are evaluated without the need for successive calculation and memorization of the system kinetic and potential energy values along the sustained fault trajectory. The method is used for determination of output features in the training phase of the neural‐net based transient security assessment. The proposed approach is tested on the well‐known ten‐generator New England test system demonstrating the validity and accuracy of obtained results. Copyright © 1993 John Wiley & Sons, Ltd.

关键词：

来源：评论

学校读者我要写书评

暂无评论

ACCURACY REQUIREMENTS FOR MEASUREMENT SYSTEMS WITH UNIFORM AND NORMAL ERRORS

引用

NAVAL ENGINEERS JOURNAL 1993年第1期105卷 66-69页

作者： SNOW, JM STUCKMAN, BE USHER, JS Jeffrey M. Snow:received his B.S. degree in mechanical engineering from the University of Washington in 1977. He has worked at Boeing Commercial Aircraft Company and Puget Sound Naval Shipyard. Since 1985 he has been at Naval Surface Warfare Center Crane Division (NSWCC). From 1987 to 1990 he was in charge of quality assurance configuration management and reliability for Aegis (SPY-1 and Mk-99) microwave tubes. He currently is in the Radar System Branch at NSWCC. He is a member of ASQC and ASME. His areas of interest include the use of statistics in process improvement efforts and objectively rating and rewarding suppliers for better quality. Bruce E. Stuckman:holds a Ph.D. degree in systems engineering from Oakland University where he also obtained M.S. and B.S. degrees in electrical and computer engineering. In 1992 Dr. Stuckman obtained his J.D. from the University of Louisville where he graduated cum laude. He is currently an associate in the patent and computer law department of Brooks & Kushman a law firm specializing in intellectual property and technology related causes. Prior to this he was an associate professor of both electrical engineering at the University of Louisville and a member of the Research Advisory Board of the South Central Bell Telecommunications Research Center. Dr. Stuckman is the author of over 75 published works in a variety of research areas including global optimization algorithms control systems communication and telecommunication systems and instrumentation electronics. He has served as a technical consultant to such organizations as Control Data Corporation General Electric General Motors Research Laboratories Gulf & Western AT&T Bell Laboratories ARCO Research and Technical Services and the U.S. Government and has been a frequent lecturer at national and international symposia. He is a senior member of IEEE and a member of ASNE Eta Kappa Nu Tau Beta Pi Sigma Xi and Phi Kappa Phi. John S. Usher Ph.D. P.E.:is an assistant professor of industrial engineering

Accuracy requirements are usually determined as a percentage of the specification range of the measured part or process. Setting accuracy requirements in this manner results in a wide and unpredictable range of false rejection and acceptance probabilities. This causes extra costs due to either: 1) over specification of measurement systems accuracy requirements;2) time, effort, retesting, and resolution of false rejections;or 3) system degradation caused by false acceptance of out-of-specification parts. Achieving a consistent and known risk of false acceptance is only possible by considering the measured process C(pk), the process's mean in relation to the center of the specification range, and the measurement system error distribution. This paper presents a method for calculating the probabilities of false rejection and false acceptance for a normal process which is measured with, alternately, uniform and normally distributed error. It is shown that under most conditions uniform error causes 20% to 30% higher false rejection and acceptance probabilities. Thus, knowledge of measurement error distribution could provide lower total production cost.

关键词：

来源：评论

学校读者我要写书评

暂无评论

PHASE-SHIFTER - A NONLINEAR CIRCUIT FOR DIRECT MEASUREMENT OF PHASE MARGIN IN FEEDBACK-control SYSTEMS 35

PHASE-SHIFTER - A NONLINEAR CIRCUIT FOR DIRECT MEASUREMENT O...

引用

35TH MIDWEST SYMP ON CIRCUITS AND SYSTEMS

作者： DANTOWITZ, P SHAFAI, B SHAFAI, E Department of Electrical and Computer Engineering Northeastern University Boston 02115 MA United States Department of Mechanical Engineering Measurement and Control Laboratory Swiss Federal Institute of Technology (ETH) Zurich 8092 Switzerland

ISBN: (纸本)0780305108

A novel nonlinear circuit called "Phase Shifter" is introduced which accurately measures the phase margin of a linear system operating in a feedback control loop. The measurement is made by inserting the phase shifter in the control loop, causing it to undergo self-sustained oscillations (limit cycle) of relatively low amplitude. It is shown that sustained oscillations occur at the gain crossover frequency and the phase margin is equal to the phase lag of the inserted circuit. A complete analysis of computing amplitude and frequency of oscillation which employs the classical sinusoidal-input describing function is also given and the stability of limit cycle and its neighborhood using the theory of integral manifolds are included. © 1992 IEEE.

关键词： Linear systems

来源：评论

学校读者我要写书评

暂无评论

Optimum pairing and ordering conditions for simultaneous reduction in total capacitance, sensitivity and output noise of cascade SC filters

Optimum pairing and ordering conditions for simultaneous red...

引用

1992 IEEE International Symposium on Circuits and Systems, ISCAS 1992

作者： Zhiqiang, M.A. Nakayama, Kenji Yamamoto, Gaishi Department of Electrical and Computer Engineering Faculty of Technology Kanazawa University Kanazawa920 Japan Faculty of Engineering Kanazawa Institute of Technology Ishikawa921 Japan Dept. of Automatic Control Engineering Central-South University of Technology Changsha China

ISBN: (纸本)0780305930

This paper presents optimum pairing and ordering (P/O) conditions for simultaneous reduction in total capacitance, sensitivity and output noise of cascade SC filters. First, investigating relations among conditions proposed for minimizing these three parameters independently, termed, CTmin, Smin and Nmin conditions, we make it clear that there is no P/O assignment with which the three parameters can be simultaneously minimized. Then we verify that Nmin condition is valid in reducing two other parameters. Trade-off optimum conditions are proposed by combining Nmin with Smin and CTmin. These conditions can limit the number of P/O assignments, in which an optimum P/O assignment for simultaneous reduction of three parameters can be searched out easily. Depending upon applications, the trade-off optimum condition can be slightly modified by adjusting the proportion of CTmin Smin and Nmin. Efficiency of the proposed trade-off optimum conditions is confirmed through computer simulation using several kinds of filters. © 1992 IEEE.

关键词： Capacitance

来源：评论

学校读者我要写书评

暂无评论

TACTILE SENSING IN FINE MOTION ROBOT TASKS

TACTILE SENSING IN FINE MOTION ROBOT TASKS

引用

1992 IEEE INTERNATIONAL SYMP ON INTELLIGENT control

作者： KLOMP, C MULLER, FL REGTIEN, PPL Delft University of Technology Department of Electrical Engineering Control Laboratory i Computer Architecture i Electronic Instrumentation P.O. Box 5031 Delft 2600 GA Netherlands

ISBN: (纸本)0780305469

The usage of a tactile image sensor for acquiring additional information about assembly tasks (or other fine motion tasks) is proposed. The sensor used is based on the piezoresistivity of a conductive polymer film (FSR). It contains 16x16 taxels (tactile elements) over an area of 4x4 cm. In order to minimize the time needed to transfer the data to the robot controller and to process the data in the robot controller, a preprocessing unit for the tactile. data is being developed. The unit must be able to detect and recognize objects, extract the position and orientation of an object and detect slip. Scanning the complete image is too time consuming, therefore only the contour points of an object will be scanned, thereafter the vertices of the contour are detected. The last step consists of matching these vertices with the vertices of the objects in the database. Sample objects have been used to show the results of the vertex detection in hardware. The data of the preprocessing unit will be used in several ways by the robot controller. The object recognition feature is used for grasp verification, after which the position of the object relative to the gripper can be used to adjust the robot position. Slip detection is used in real time as an indication of errors while performing assembly operations. During these operations the robot will be controlled, based on force and position information (active compliance). The implementation of the proposed algorithms will be performed with transputer based hardware, which is currently being developed. Tests with a prototype board of the hardware have shown that the desired sample rates (S lms) can easily be obtained. © 1992 IEEE.

关键词： Polymer films

来源：评论

学校读者我要写书评

暂无评论

On time-sub-optimal control using artificial neural networks

On time-sub-optimal control using artificial neural networks

引用

IEEE Conference on Decision and control

作者： R.R. Zakrzewski R.R. Mohler Institute of Automatic Control Warsaw University of Technology Poland Department of Electrical and Computer Engineering Oregon State University Corvallis OR USA

It is demonstrated how a neural network may be used to generate a time-suboptimal control policy in continuous time. Approximation of optimal feedback by neural networks is proposed. Training data are taken from a set of precalculated open-loop trajectories from which a neural network extracts the information about the mapping in question. Simulation results are provided for a simple example.< >

关键词： Artificial neural networks Open loop systems Neurofeedback Training data Trajectory Data mining

来源：评论

学校读者我要写书评

暂无评论

Adaptive Systems Performance in the Frequency Domain

引用

IFAC Proceedings Volumes 1992年第14期25卷 131-137页

作者： B. Egardt L. Ljung C.R. Johnson G.A. Williamson Control Engineering Laboratory Chalmers University of Technology S-412 96 Göteborg Sweden Department of Electrical Engineering Linköping University S-581 83 Linköping Sweden School of Electrical Engineering Cornell University Ithaca NY 14853 USA Department of Electrical and Computer Engineering Illinois Institute of Technology Chicago IL 60616 USA

The paper reviews some of the emerging techniques for assessment of adaptive schemes by use of frequency domain oriented performance measures. These measures are believed to provide a useful complement to traditional, parameter oriented measures, often used in the adaptive signal processing area. The frequency domain characterization provide strong links to engineering practice and thus has the potential to guide in the search for algorithm modifications that improve performance in practical implementations. The paper reviews available results for the LMS algorithm in terms of bias and variance and gives som extension of previous results for the characterization of convergence rates in the frequency domain. Extensions to more general cases, including the use of leakage, are briefly discussed.

关键词： Adaptive filtering identification least-squares estimation frequency domain

来源：评论

学校读者我要写书评

暂无评论

Application of Neural Networks Methodology to Power System Modelling and control

Application of Neural Networks Methodology to Power System M...

引用

American control Conference (ACC)

作者： Radoslaw R. Zakrzewski Ronald R. Mohler Institute of Automatic Control Warsaw University of Technology Warsaw Poland Department of Electrical & Computer Engineering Oregon State University Corvallis OR USA

Artificial feedforward networks are studied as nonlinear function approximators used to identify forward and inverse mappings of discrete time dynamic systems. They are found to provide significant advantages over other modelling techniques such as polynomial approximations, especially if the extrapolation beyond the region covered by the learning data is involved. We apply the neural network methodology to a simple second order approximation of a single-machine infinite-bus power system controlled by means of modifying the reactance of the line. Accurate off-line identification of forward and inverse dynamics of the system is performed by means of single hidden layer neural networks, and both models are then used in a direct inverse control configuration. The controller simulations show very good quality of transients for severe short-circuit fault.

关键词： Power system modeling Neural networks Power system control Power systems control system synthesis Power system dynamics Power system simulation Artificial neural networks Nonlinear dynamical systems Polynomials

来源：评论

学校读者我要写书评

暂无评论

Hybrid state analysis method in stochastic Petri nets

Hybrid state analysis method in stochastic Petri nets

引用

IEEE International Conference on Systems, Man and Cybernetics

作者： Z. Huang J. Wang M. Zhou Department of Automatic Control East China University of Science and Technology Nanjing China Department of Electrical and Computer Engineering New Jersey Institute of Technology Newark USA

The authors consider the analysis of stochastic Petri net models with generally distributed transition firing times. A so-called hybrid state analysis method is developed. The basic idea is to make the extended state, i.e., the hybrid state, which is composed of a marking and the enabling times of enabled transitions under the marking, propagate as a Markov process by the inclusion of supplementary variables. The recursive equation of hybrid state density functions is given.< >

关键词： Stochastic processes Petri nets Delay Markov processes Equations Density functional theory Stochastic systems Discrete event systems Fires Performance analysis

来源：评论

学校读者我要写书评

暂无评论

Phase shifter: a nonlinear circuit for direct measurement of phase margin in feedback control systems

Phase shifter: a nonlinear circuit for direct measurement of...

引用

Midwest Symposium on Circuits and Systems (MWSCAS)

作者： P. Dantowitz B. Shafai E. Shafai Department of Electrical and Computer Engineering Northeastern University Boston MA USA Department of Mechanical Engineering Measurement and Control Laboratory Swiss Federal Institute of Technology Zurich Switzerland

A nonlinear circuit called phase shifter is introduced. It accurately measures the phase margin of a linear system operating in a feedback control loop. The measurement is made by inserting the phase shifter in the control loop, causing it to undergo self-sustained oscillations (limit cycle) of relatively low amplitude. It is shown that sustained oscillations occur at the gain crossover frequency, and that the phase margin is equal to the phase lag of the inserted circuit. A complete analysis of computing amplitude and frequency of oscillation which employs the classical sinusoidal-input describing function is also given, and the stability of limit cycle and its neighborhood using the theory of integral manifolds is included.< >

关键词： Phase shifters Nonlinear circuits Phase measurement Limit-cycles Frequency Linear systems Feedback control Circuit analysis Circuit stability Stability analysis

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：