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IEEE/PES Transmission and Distribution Conference and Exposition: Latin America

作者： K. L. S. Shenxing X. Dong Z. Bo State Key Lab of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing 100084 China Tsinghua University Beijing Beijing CN State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing China AREVA T&D Automation슠and Information Systems Stafford UK

Non conventional instrument transformer (NCIT) and IEC 61850 are crucial technologies in digital substations. But they bring some new uncertainties to protection IEDs, especially the time synchronization issue in current differential protection. The paper analyzes the time delay of transferring sampled values from NCIT to current differential relay in NCIT and IEC61850 based digital substation, then finds out the delay-non-deterministic problem, at last presents a novel current differential protection scheme by using phase-locked loops (PLL ) technology.

关键词： Substations Delay effects Ethernet networks Phase locked loops IEC Synchronization Data communication

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Current differential protection based on Non-Conventional Instrument Transformer and IEC61850

Current differential protection based on Non-Conventional In...

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International Universities Power engineering Conference (UPEC)

作者： Kun Liu Xinzhou Dong Zhiqian Bo State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing China AREVA T&D Automation슠and Information Systems Staffordshire UK

Non Conventional Instrument Transformer (NCIT) and IEC 61850 are crucial technologies in digital substations. But they bring some new uncertainties to protection IEDs, especially the time synchronization issue in current differential protection. The paper analyzes the time delay of transferring sampled values from NCIT to current differential relay in NCIT and IEC61850 based digital substation, then finds out the delay-non-deterministic problem, at last presents a novel current differential protection scheme by using Phase-Locked Loops (PLL ) technology.

关键词： Substations Delay effects Synchronization IEC Phase locked loops Data communication Ethernet networks

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Packet-loss dependent controller design for networked control systems via switched system approach

Packet-loss dependent controller design for networked contro...

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IEEE Conference on Decision and control

作者： Junyan Yu Long Wang Mei Yu Yingmin Jia Jie Chen Intelligent Control Laboratory Center for Systems and Control College of Engineering Peking University Beijing China Department of Automation North China Electric Power University Zhuxinzhuang Beijing China The Seventh Research Division Beihang University Beijing China Beijing Institute of Technology Key Laboratory of Complex System Intelligent Control and Decision Ministry of Education Beijing China

ISBN: (纸本)9781424431236

The stabilization problem of networked control systems with bounded packet loss is addressed. We model such networked control systems as a class of switched systems, and present sufficient conditions for the stabilization by using a packet-loss dependent Lyapunov function. Moreover, different from existing results, we propose the design for packet-loss dependent stabilizing controllers for two types of packet-loss processes: one is a arbitrary packet-loss process, and the other is a Markovian packet-loss process. Several numerical examples and simulations are worked out to demonstrate the effectiveness of the proposed design technique.

关键词： control systems Networked control systems Switched systems Sufficient conditions Optimal control Delay effects Communication system control Communication system traffic control Feedback control Electrical equipment industry

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control of Formations of UAVs for Surveillance and Reconnaissance Missions

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IFAC Proceedings Volumes 2008年第2期41卷 5161-5166页

作者： T. Kopfstedt M. Mukai M. Fujita C. Ament Research and Development Diehl BGT Defence GmbH und Co. KG 88662 Ueberlingen Germany (Tel: +49-7551-892875 Department of Electrical and Electronic Systems Engineering Kyushu University Fukuoka 819-0395 Japan Department of Mechanical and Control Engineering Tokyo Institute of Technology Tokyo 152-8552 Japan System Analysis Group Technical University of Ilmenau 98693 Ilmenau Germany

This paper presents a method for control of formations of Unmanned Aerial Vehicles (UAVs) in urban environments with several obstacles. Therefore the trajectories for each UAV are planned using mixed integer quadratic programming (MIQP) to describe a minimization problem. The result of this minimization problem then characterizes a collision free trajectory for each UAV using the commanded formations to fulfil the missions. The description of the UAVs, the inter UAV collision avoidance, the collision avoidance with obstacles as well as the description of formations will be shown in detail together with some simulation results in this paper. In addition the introduction explains the fields of interest in such formations of UAVs and what kind of advantage they can bring in comparison to today's solutions. The novelty in the approach in this paper is the description of formations of UAVs used in combination with MIQP to change formations, to add additional UAVs into an existing formation and to split formations, simply by changing some parameters in the description of the formation.

关键词： Autonomous systems Description of Formation Flights Hybrid systems Optimal control Mixed Integer Quadratic Programming

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Test results of critical elements for reusable rocket engine

Test results of critical elements for reusable rocket engine

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作者： Yoshida, Makoto Takada, Satoshi Naruo, Yoshihiro Niu, Kenichi 1 Koganezawa Kimigaya Kakuda Miyagi 981-1525 Japan Mitsubishi Heavy Industries Co. Ltd. 1200 Higashi-tanaka Komaki Aichi 485-8561 Japan Rocket Engine System Section Space Transportation Mission Directorate Japan Mechanism and Structure Section Space Transportation Mission Directorate Japan Department of Space Systems and Astronautics ISAS 3-1-1 Yoshinodai Sagamihara Kanagawa 229-8510 Japan Liquid Rocket Design Section Engine and Control Equipment Engineering Department Japan

ISBN: (纸本)9781563479434

A 30-kN rocket engine, a pilot engine, is being developed in Japan. Development of this pilot engine has been initiated in relation to a reusable sounding rocket, which is also being developed in Japan. This rocket takes off vertically, reaches an altitude of 100 km, lands vertically at the launch site, and is launched again within several days. Due to the advantage of reusability, successful development of this rocket will mean that observation missions can be carried out more frequently and economically. In order to realize this rocket concept, the engines installed on the rocket should be characterized by reusability, long life, deep throttling and health monitoring, features which have not yet been established in Japanese rocket engines. To solve the engineering factors entailed by those features, a new design methodology, advanced engine simulations and engineering testing are being focused on in the pilot engine development stage. Especially in engineering testing, limit condition data is acquired to facilitate development of new diagnostic techniques, which can be applied by utilization of the mobility of small-size hardware. In this paper, the development status of the pilot engine is described, including fundamental design and engineering tests of the turbopump bearing and seal, turbine rig, injector and combustion chamber, and operation and maintenance concepts for one hundred flights by a reusable rocket are examined. © 2008 by the American Institute of Aeronautics and Astronautics, Inc.

关键词： Reusability

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Nonisothermal stirred-tank reactor with irreversible exothermic reaction A → B: 1. Modeling and local control

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Lecture Notes in control and Information Sciences 2007年 361卷 3-32页

作者： Albertos, P. Pérez-Polo, M. Department of Systems Engineering and Control ETSII Spain Department of Physics System Engineering and Signal Theory EPS Spain

ISBN: (纸本)3540731873

In this chapter, the nonlinear and linear mathematical model of a CSTR where an irreversible exothermic reaction takes place is considered. From the analysis of the steady states, the curves of removed and generated heat are deduced in order to determine the equilibrium point and the transfer function of the reactor. Considering a set of reactors ranging from small to high volume, it is shown that the open-loop transfer function can be conditionally stable, and the effect of the scaling-up is investigated by means of the root locus. Reactor and jacket equilibrium temperatures vs. reactor volume are deduced in order to obtain an intuitive notion of the reactor controllability. The problem of the local control of a single loop concentration and cascade temperature control from the linearized model previously considered is analyzed by using PI controllers. Several examples considering step responses to changes in the concentration and temperature references are considered. Finally, the decoupling and the feedback control of the reactor by using the pole-placement technique have been also considered. © 2007 Springer-Verlag Berlin Heidelberg.

关键词： Transfer functions

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Nonisothermal stirred-tank reactor with irreversible exothermic reaction A → B: 2. Nonlinear phenomena

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Lecture Notes in control and Information Sciences 2007年 361卷 243-279页

作者： Pérez-Polo, M. Albertos, P. Department of Physics System Engineering and Signal Theory EPS Spain Department of Systems Engineering and Control ETSII Spain

ISBN: (纸本)3540731873

In this chapter, the non-linear dynamics of a nonisothermal CSTR where a simple first order reaction takes place is considered. From the mathematical model of the reactor without any control system, and by using dimensionless variables, it has been corroborated that an external periodic disturbance, either inlet stream temperature and coolant flow rate, can lead to chaotic dynamics. The chaotic behavior is analyzed from the sensitivity to initial conditions, the Lyapunov exponents and the power spectrum of reactant concentration. Another interesting case is the one researched from the self-oscillating regime, showing that a periodic variation of coolant flow rate can also produce chaotic behavior. Finally, steady-state, self-oscillating and chaotic behavior with two PI controllers have been investigated. From different parameters of the PI controllers, it has been verified that a new self-oscillating regime can appear. In this case, the saturation in a control valve gives a Shilnikov type homoclinic orbit, which implies chaotic dynamics. The existence of a new set of strange attractors with PI control has been analyzed from the initial conditions sensitivity. An Appendix to show a computationally simple form to implement the calculation of Lyapunov exponents is also presented. © 2007 Springer-Verlag Berlin Heidelberg.

关键词： Lyapunov methods

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An Indoor Localization Algorithm for Lighting control using RFID

An Indoor Localization Algorithm for Lighting Control using ...

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IEEE Energy 2030 Conference, ENERGY

作者： Zi-Ning Zhen Qing-Shan Jia Chen Song Xiaohong Guan Department of Automation Tsinghua University Beijing China Center for Intelligent and Networked Systems (CFINS) Tsinghua National Laboratory for Information Science and Technology Department of Automation Tsinghua University Beijing China United Technologies Research Center China and the Tsinghua-UTC Research Institute for Integrated Building Energy Safety and Control Systems Beijing 100084 P. R. China (phone: +86-10-62772183 fax: +86-10-62770554 e-mail: songc@***) SKLMS Laboratory and System Engineering Institute Xi''an Jiaotong University Xi'an China

Occupant's identity and location are important information for lighting control in order to reduce the energy consumption while increasing livelihood. While active RFID system provides occupant's identity, it is nontrivial to localize the occupant's location in an indoor environment due to the multipath effect, the changing environment, and the unreliable communication link. In this paper, we implement a system with multiple active RFID readers, and develop a localization algorithm based on support vector machine (SVM). The algorithm uses round-robin comparison to localize the occupant to one of the multiple regions in a floor. The geometric relationship among the rooms and the historical localization data are used to further improve the localization accuracy. Numerical results demonstrate a high localization accuracy of this algorithm. We hope this work sheds insight on lighting control for energy saving and an increased livelihood.

关键词： Lighting control Radiofrequency identification Energy consumption Active RFID tags Educational institutions Indoor environments Round robin Support vector machines Humans Safety

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Ka-band Active Phased Array Antenna

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Journal of the National Institute of Information and Communications Technology 2007年第4期54卷 53-58页

作者： Yajima, Masanobu Kuroda, Tomonori Maeda, Tsuyoshi Shimada, Masaaki Hasegawa, Takumi Kitao, Shiro Hariu, Ken-Ichi Space Engineering Development Co. Ltd. Satellite Communications Antenna Systems Space Systems Department Satellite Payload System Section Mitsubishi Electric Corporation Space Systems Integration and Test Department Test and Quality Control Section Mitsubishi Electric Corporation

Active Phased Array Antenna (APAA) is one of mission equipment on WINDS and the frequency band is Ka band, and maximum data rate 1.2 Gbps communication will be realized by APAA. It consists of 128 element antennas and many extremely minaturized RF modules. It can scan two beams of a transmitting antenna and a receiving antenna electronically and independently. WINDS service area covers almost all of the world which is a visible region from the satellite by APAA. This paper introduces APAA role, background, functions, key technologies, and major specifications, and describes development results.

关键词： Antenna phased arrays

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Parallel digital signal processing using multi-issue instructions

Parallel digital signal processing using multi-issue instruc...

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Signal Processing: Algorithms, Architectures, Arrangements, and Applications, SPA 2007

作者： Dabrowski, Adam Pawlowski, Pawel Marciniak, Tomasz Poznań University of Technology Department of Control and System Engineering Division of Signal Processing and Electronic Systems ul. Piotrowo 3a 60-965 Poznań Poland

ISBN: (纸本)9781424415144

This paper presents aspects of parallelism of computations in processing of signals using digital signal processors (DSPs) with multi-issue assembler instructions. We present general features of the contemporary DSPs with special attention paid to the VLIW architecture. In order to illustrate the multi-issue instruction technique we analyze performance of the fixed-point Blackfin processor by means of chosen typical signal processing tasks realized using VisualDSP++ 4.5 environment with Software Development Kit 2.01. Aspects of the floating-point processing are analyzed using Sharc and TigerSharc processors. © 2007 IEEE.

关键词： Digital signal processors

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