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Instantaneous power measurement in time-frequency domain

EUROPEAN TRANSACTIONS ON electrical POWER 1996年第5期6卷 351-356页

作者： Andria, G Attivissimo, F Savino, M [?]Dr. Gregorio Andria (1956). AEI received the M.S. degree in Electrotechnical Engineering in 198 I andthe Ph.D. degree in Electrical Engineering in 1987 from the State Polytechnic of Bdtaly. From 1981 he was working in the Electrotechnics and Electronics Department of the same University as a member of the research team on electrical measurements. His research interests are in the field of electrical and electronic measurements on components and systems including digital measurements for the analysis of electrical quantities in time-varying non-sinusoidal systems and the design of integrated optical sensors for measurement and control of nonelectrical physical quantities. (Department of Electrotechnics and Electronics Faculty of Engineering Polytechnic of Bari via E. Orabona 4 I-70125 Bari Italy T +3980/ 54603 18 Fax +39 80/54604 10 e-mail labmisure@deect103.poliba.it)

The paper deals with an original application of the Short-Time Fourier Transform (STFT) to instantaneous power measurements. This technique can be easily implemented in a dedicated instrument to perform accurate time-frequency analysis of the time-varying harmonic contents of network powers (in their active and imaginary components), which are typically non-stationary signals. Moreover new algorithms have been examined carefully and developed to attain high levels of accuracy, flexibility and efficiency through STFT-PD (Power Distribution), Particularly, optimized interpolation formulas were used, derived from the windowing theory to reduce the negative effects due to leakage during instantaneous frequency changes. The effectiveness of the suggested technique and particularly, the high level of accuracy achieved in time-varying amplitude and frequency measurements of the analysed components of instantaneous powers and currents has been proven by means of suitable simulations.

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New impulse sampled IIR switched-capacitor interpolators

New impulse sampled IIR switched-capacitor interpolators

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IEEE International Conference on Electronics, circuits and systems (ICECS)

作者： U Seng Pan R.P. Martins J.E. Franca Faculty of Science and Technology University of Macau Macau Macao China Instituto Superior Técnico Department of Electrical Engineering and Computers Integrated Circuits and Systems Group Lisboa Portugal

This paper presents new Switched-Capacitor (SC) Infinite Impulse Response (IIR) Interpolators employing an efficient combination of Active-Delayed Blocks (ADB) polyphase structures and recursive direct-form II structures with frequency responses no longer affected by the input sample-and-hold filtering effect. Two different architectures are analysed: the first requires slower Operational Amplifiers (OAs) while the second allows the reduction of the number of clock phases and ADBs (1 OA per ADB). Examples are given to illustrate the behaviour of both types of SC interpolators with arbitrary input signal formats.

关键词： Finite impulse response filter IIR filters Filtering Clocks Transfer functions Sampling methods circuits Delay Electronic mail Frequency

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System engineering of computer integrated manufacturing

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NAVAL ENGINEERS JOURNAL 1996年第6期108卷 59-71页

作者： Habayeb, AR Abdul R. Habayeb Ph.D. is the weapons command and control technology administrator for the Naval Air Systems Command in Washington D.C. He is recognized in the industry for his work in systems integration and systems effectiveness. His extensive engineering background includes design of logic circuits and control systems performance reliability assessments and analysis and quantification of weapons systems effectiveness. Dr. Habayeb has published several papers reports and a book entitled Systems Effectiveness. Dr. Habayeb previously served as dean of the faculty of engineering and chairman of the electrical engineering department at Yarmouk University in Jordan. Dr. Habayeb has taught systems engineering courses at the University of Maryland and The George Washington University. He holds several patents in the field of switching circuits and data communication and is a senior member of IEEE and Sigma Xi.

Technologies to manufacture affordable systems are of very high interest to naval aviation, the Navy, other services and industry. The current environment of downsizing and continued budget reduction is causing DoD to seek effective methods to improve the affordability and availability of critical devices. Computer integrated manufacturing (CIM) and flexible manufacturing (FM) proved to be the appropriate choice for cost effective manufacturing. CIM deals with the effective utilization of computers and automation in manufacturing to improve production (quality yield, cycle time) and reduce the unit product cost. This paper uses a system engineering approach to formulate the architecture and design of an infrared focal plane array CIM factory. A system engineering approach deals with the total issue of building systems: the determination of the requirements, establishing the architecture, performing system partitioning and integration of hardware and software, applying the evaluation measures (metrics), and doing design tradeoff analyses of options and alternatives. At a given partitioning level, system integration is the process of blending hardware and software building blocks into a unified functioning whole. Computer integrated manufacturing is considered the integration of mini-factories (clusters of workcells) through a distributed computing environment (DCE) and the automation of manufacturing processes.

关键词： Computer integrated manufacturing

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Composition of Conflict-Free Petri Net Models for control of Flexible Manufacturing systems

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IFAC Proceedings Volumes 1996年第1期29卷 547-552页

作者： B. Hrúz A.J. Niemi T. Virtanen Slovak Technical University Faculty of Electrical Engineering and Information Technology Department of Automatic Control Systems Ilkovicova 3 812 19 Bratislava Slovak Republic phone: +42 -7-791698 Helsinki University of Technology Department of Information Technology Control Engineering Laboratory Otakaari 5A FIN-02150 Espoo Finland phone: +358-0-4513334

An approach using Petri nets to modelling and control of flexible manufacturing systems (FMS) is worked out in the paper. A class of Petri nets suitable for the modelling of FMS and for the design of their control is formulated. In the Petri net models not only conflicts due to mutual exclusions of the shared system resources but conflicts of branching operations are analyzed and solved, as well. Models of FMS suitable for system performance analysis and control design are built up of a set of elementary building blocks proposed in the paper. Analysis, modelling method and control design is developed on the background of a pilot experimental FMS developed at the Helsinki University of Technology.

关键词： Discrete event dynamic systems flexible manufacturing systems Petri nets control oriented models

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ADAM: adaptive autonomous machine

ADAM: adaptive autonomous machine

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Euromicro Workshop on Advanced Mobile Robot

作者： D.C. van Oosten L.F.J. Nijenhuis A.W.P. Bakkers W.A. Vervoort Dutch Open University Heerlen Netherlands Electrical Engineering Faculty Control Laboratory University of Twente Enschede Netherlands Informatics Department Systems Programming and Architecture University of Twente Enschede Netherlands

This paper describes a part of the development of an adaptive autonomous machine that is able to move in an unknown world extract knowledge out of the perceived data, has the possibility to reason, and finally has the capability to exchange experiences and knowledge with other agents. The agent is not pre-programmed by its designer but was given simple rules of life, i.e. what is good and what is bad. By evaluating its sensor inputs these rules of life were transformed into a rule based reactive system. Simulations of the system showed that the agent is able to learn by its own experience. By representing the learned knowledge in an appropriate way, the acquired knowledge could be judged on its effectiveness and also this knowledge could be shared with other, less experienced agents.

关键词： Sensor systems Laboratories Electronic mail Informatics Data mining Artificial intelligence Humans Robot sensing systems Filters Actuators

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ADAM: Adaptive autonomous machine 1

ADAM: Adaptive autonomous machine

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1st Euromicro Workshop on Advanced Mobile Robots, EUROBOT 1996

作者： Van Oosten, Daan C. Nijenhuis, Lucas F.J. Bakkers, Andre W.P. Vervoort, Wiek A. Dutch Open University P.O. Box 2960 Heerlen6401 DL Netherlands Control Laboratory University of Twente Electrical Engineering Faculty P.O.Box 217 Enschede7500 AE Netherlands Systems Programming and Architecture University of Twente Informatics Department P.O.Box 217 Enschede7500 AE Netherlands

ISBN: (纸本)0818676957

关键词： Knowledge management

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Linear-programming-based method for optimum schedule of reactive power sources in power systems

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EUROPEAN TRANSACTIONS ON electrical POWER 1996年第1期6卷 31-37页

作者： AbdelSalam, MM ElSadek, MZ Hussein, AI Hussein, AA Mazen Abdel-Salam (1946) received the B.Sc. degree in 1967 The M.SC. degree in 1970 and the Ph.D. degree in 1973 all in Electrical Engineering from the University of Cairo Egypt. In 1967 he was with the Academy of Science and Technology Cairo as a Research Assistant. In 1973 he joined the faculty of Electrical Engineering at Assiut University Egypt as an Assistant Professor and in October 1977 he became an Associate Professor. During the academic years of 1977 to 1979 he was an Alexander-von-Humboldt Fellow in the Electrical Engineering Department TU Munic/Germany and the Electrical Engineering Department University of Liverpoo YGB. In September 1979 he began work as a Researcher with General Electric Co. Pittsfield MANSA. In January 1982 he rejoined Assiut University as a Professor of Electrical Power Engineering. During the academic years of 1982 to 1984 he was Professor in the Department of Electrical Engineering University of Jordad Amman. During the academic years of 1982 to 1984 he was a visiting Full Professor in the Department of Electrical Engineering Michigan Technological University Houghton NSA. From 1990 to 1994 he was a Professor of Electrical Power Engineering in the Department of Electrical Engineering at King Fahd University of Petroleum & Minerals Dhahran/Saudi Arabia. He had obtained Research Fellowships at the Military Technical University of Hamburg Eemany in 1984 at the University of Leedd GB in 1988 at Kaiserslautern University/Germany in 1989 and at Michigan Technological University in 1990. He is currently a Professor of Electrical Power Engineering Assiut University. His research activities include corona studies digital calculation of electric fields investigations of high-voltage phenomena low-voltage distribution networks and control of electrical machines. He is a fellow of the Institution of Electrical Engineers Londod GB and of the Institute of Electrical and Electronic Engineers New York AJSA. (Assiut University Electrical Engineering Departmen

This paper proposes a linear-programming optimization-based method for reactive power scheduling using generator terminal voltages and reactive outputs, transformer tap-settings and switchable reactive power sources as control variables. Dual linear programming is applied to minimize a composite objective function consisting of the cost of the adjusted control variables and the system transmission losses. The proposed composite objective function is more economical than that of the minimum total adjustment of the control variables and calls for less adjustments of var sources to meet the desired voltage limits. The proposed method is applicable to practical transmission and distribution networks, 500 kV to 11 kV of small and large sizes.

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Development of transient stability controller system (TSC) based on on-line stability calculation

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electrical engineering IN JAPAN 1996年第4期117卷 61-79页

作者： Ota, H Inoue, T Ito, H Fukushima, N Omata, K Morita, K Kokai, Y Chubu Electric Power Co. Graduated in 1955 from the Department of Electrical Engineering of the Faculty of Engineering University of Tokyo and joined Chubu Electric Power Co. in the same year. He is engaged mainly in developing technology for construction planning as well as protection stabilization and automatic control of power systems. He is currently a Director and Vice President of the company. He received an OHM Technology Award in 1971 and an Achievement Award from the I.E.E. Japan in 1992. Graduated in 1962 from the Department of Electrical Engineering Shibaura Institute of Technology and joined Chubu Electric Power Co. in the same year. He is engaged in the development of technology for large-scale centralized control of power systems as well as the networking of control computers. He is currently a System Analysis Group Chief in the System Operation Division of the company. Graduated in 1985 from the Department of Electronics and Electrical Engineering of the Faculty of Engineering Tokyo Institute of Technology and joined Chubu Electric Power Co. in the same year. He is engaged mainly in the development of technology for power system protection and stabilization. He is currently working in the System Analysis Group of the System Operation Division of the company. Toshiba Corporation Graduated in 1967 from the Department of Electrical Engineering University of Tokyo and joined Toshiba Corporation in the same year and engaged in development of power system control systems in Japan and abroad. He is currently a Chief of System Technology in the Power System Technology Division of the company. He is a member of the Theses Subcommittee of the 1995 World Energy Conference. He is an Assistant Secretary of the Japanese Committee of CIGRE and a member of the Japanese Subcommittee of CIGRE SC35 and 39. He is a member of IEEE. Completed his Master's course at the Science and Engineering Research Division of the Graduate School Waseda University in 1980 and joined Toshiba Corporation in the same year. H

A new transient stability controller system (TSC) based on on-line transient stability calculation has been developed. The TSC system prevents the power system from wide-area blackout by shedding generators optimally when a serious fault occurs. This system consists of a central processing unit (TSC-P), and four local units for fault detection (TSC-C), and seventeen units for generator shedding(TSC-T). The TSC-P selects optimal generators to be shed for stabilization based on on-line transient stability calculation for contingencies at 500 kV lines and buses every five minutes. The results are transmitted to the TSC-Cs periodically. Should any fault occur, only one TSC-C will detect the fault occurrence and send control signals to the TSC-Ts which actually generate shedding signals. To realize the TSC system, essential are fast stability evaluation methods for a large number of contingencies and effective selection methods of optimal generators to be shed for stabilization. This paper presents total algorithms applied in the TSC-P, the results of algorithm verification tests using a prototype system combined with a large-scale analog simulator, and the characteristics of the actual system.

关键词： power system stabilization generation shedding on-line stability calculation screening parallel calculation

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Soliton system evaluations using fibers with dispersion and loss fluctuations

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART II-ELECTRONICS 1996年第4期79卷 77-84页

作者： Ishiba, K Komatsu, T Takahara, M Faculty of Engineering Yamanashi University Kofu Japan 400 Graduated in 1994 from the Department of Electronic and Information Engineering where he is currently in the Master's program. He has been engaged in research on optical fiber soliton transmission. Received his B.S. and M.S. degrees in 1993 and 1995 respectively from the Department of Electronic and Information Engineering Yamanashi University. He joined NTT in April 1995. He has been engaged in research on simulation of the optical fiber soliton transmission and on the transmission system with flexibility in transmission speed. Graduated from the Department of Electrical Engineering Yamanashi University in 1965 and received his M.S. degree in 1967. He received his Ph.D. degree later. In 1967 he became a Research Associate of the Department of Electronic Engineering Yamanashi University. In 1991 he became a Professor of Electronic and Information Engineering. He has been engaged in research on special function theory nonlinear circuits optical communication systems and LAN systems. In 1984 he received a Book Award from I.E.I.C.E. In 1990–91 he was on leave at Southampton University. He is a member of IEEE.

In the development of practical multimedia systems, greater capacity is desired in a long-distance large-capacity transmission system. A number of studies have been undertaken to develop a long-distance large-capacity system. Several long-distance transmission experiments for high-density transmission by wavelength demultiplexing method (WDM) have been reported recently. However, more of the experimental examples have reported on soliton transmission than on WDM systems. Hence, the former is considered more advanced. It is necessary to prepare a fiber of a length of approximately 10,000 km for ultralong-distance transmission experiment. Since this is difficult to obtain, repetitive experiments are often the case. However, such an experiment does not disclose the effects of dispersion and loss fluctuation in the fiber. In this paper, the effect of fluctuation in dispersion and loss in the fiber is studied by simulation so that the resilience of the soliton to the variations of the fiber characteristics is evaluated.

关键词： optical soliton dispersion fluctuation loss fluctuation Gordon-Haus jitter

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Wavelet transform-based signal waveform discrimination for inspection of rotating machinery

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electrical engineering IN JAPAN 1996年第2期117卷 80-92页

作者： Tamaki, K Matsuoka, Y Uno, M Kawano, T Hitachi Ltd. Received his Master's degree in 1986 in Electrical Engineering from Keio University. He joined Hitachi Ltd. in April of the same year. He is engaged in research and development of automatic production facilities particularly in research and development of servo control systems and signal processing systems. He is currently an Engineer at the company's Production Engineering Research Laboratory. He is a member of the Society of Instrument and Control Engineers and IEEE. Graduated in 1991 from the Department of Production Engineering of the Faculty of Engineering Yokohama National University and joined Hitachi Ltd. He is engaged in research and development of automatic production facilities particularly in research and development of signal processing systems. He is currently working at the company's Production Engineering Research Laboratory. Received his Master's degree in 1975 in Precision Engineering from Shizuoka University and then joined Hitachi Ltd. He is engaged in research on automatic adjustment and assembly technologies as well as development of their equipment. He is currently a Senior Engineer at the company's Production Engineering Research Laboratory. He is a member of the Japan Society of Mechanical Engineers and the Japan Society for Precision Engineering. Graduated in 1961 from the Department of Mechanical Engineering Tohoku University. He received his Ph.D. degree in Mechanical Engineering from Tokyo University in 1993. He joined Hitachi Ltd. in October 1970. He is engaged in research and development of automatic assembly technology and assembly equipment as well as inline process technology and process equipment. Since 1995 he has been with Ishinomaki Senshu University where he is currently a Professor. He is a member of the Japan Society of Mechanical Engineers and the Japan Society for Precision Engineering.

This paper presents a new discrimination procedure of signal waveforms based on wavelet theory for the inspection of rotating machinery. The wavelet transform decomposes signals into time-frequency space, rather than mere frequency space, limited by the uncertainty principle. This decomposition permits time-frequency analyses and provides a more flexible means of signal processing than before. To examine a rotary compressor pump, particular waves in the rotational load torque signals that correlate with failure modes are discriminated from one another and evaluated. To extract the focal waves, the signal is decomposed with wavelets and then only particular waves, such as impulses, are reconstructed from a selected set of wavelet coefficients. This is called time frequency space filtering. The wavelet local modulus maxima are used to pen a time-frequency window through which only the focal waves can pass with high fidelity. The maxima have information of the inflection points of the wave at each resolution that represent its waveform. The experimental results show the effectiveness of the procedure.

关键词： wavelets signal processing time-frequency analysis multiresolution decomposition inspection rotating machinery

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