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IEEE Winter Meeting Power Engineering Society

作者： A. Takizawa Y. Ono S. Inaka K. Konno Y. Nozaki T. Suzuki S. Yamazaki S. Saito T. Shirone Kokubu Works Hitachi and Limited Ibaraki Japan Tokyo Electric Consruction Office East Japan Railway Company Limited Tokyo Japan Mechanical Engineering Laboratory Hitachi and Limited Ibaraki Japan Power & Industrial System R&D Division Hitachi and Limited Ibaraki Japan

In order to handle increasing demand for electric power and protection against fires in large cities, larger-capacity and higher voltage SF/sub 6/ gas-insulated transformers have been developed and are in practical use. They use high pressure gas to enhance cooling and insulating performance. However, they have some drawbacks such as higher noise and heavier tank. We carried out developments to enlarge the ranges of capacity and voltage to which low pressure gas can be applied. Firstly, its interior structures and cooling system were designed using thermo-fluid and gas flow analyses. Secondly, electric field stresses in the transformer were kept under control by the adjustment of relative permittivities and position of insulators. Thirdly, a low-noise type gas blower was developed after careful tests. As a result, 100 MVA 154 kV SF/sub 6/ gas-insulated transformer of 65 dB class using low pressure SF/sub 6/ gas (0.24 MPa at 20/spl deg/C) has been developed.

关键词： Power transformer insulation Cooling Protection Fires Cities and towns Gas insulation Low voltage Fluid flow Thermal stresses Stress control

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On the use of LSF intermodel interlacing property for spectral quantization

On the use of LSF intermodel interlacing property for spectr...

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IEEE Workshop on Speech Coding Proceedings

作者： Mi Suk Lee Hong Kook Kim Seung Ho Choi Hwang Soo Lee Department of Electrical Engineering Korea Advanced Institute of Science and Technology Daejeon South Korea AT and T Research Laboratories Florham Park NJ USA Human & Computer Interaction Laboratory Samsung Advanced Institute of Technology Gyeonggi South Korea Central R&D center SK Telecom Daejeon South Korea

The line spectral frequencies (LSFs) extracted from successive analysis orders are interlaced with each other. This intermodel interlacing property gives a new relationship between the closeness of LSFs and their spectral sensitivities, which enables us to propose a weighting function for LSF distortion measurement. By applying the proposed weighting function to an LSF quantizer, we can achieve better performance than when using the conventional heuristic functions. Moreover, the complexity of the proposed weighting function is much lower than that of the optimal weighting function, while their performances are almost the same.

关键词： Quantization Frequency Covariance matrix distortion measurement Linear predictive coding Euclidean distance Weight measurement Polynomials reflection Humans

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A converter transformer with series-connected line-side windings for a dC link using voltage source converters

A converter transformer with series-connected line-side wind...

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IEEE Winter Meeting Power Engineering Society

作者： T. Nakajima H. Suzuki K. Izumi S. Sugimoto H. Yonezawa Y. Tsubota Power Electronics Group Power Engineering R&D Center Tokyo Electric Power Company Inc. Yokohama Japan Power Engineering Department Yokosuka Research Laboratory Central Research Institute of Electric Power Industry Japan Power System Group Electric Power Research & Development Center Chubu Electric Power Company Inc. Japan Power System Engineering & Operation Kansai Electric Power Company Inc. Japan Substation & HVDC Engineering Group Electrical Engineering Department Electric Power Development Company Limited Japan

A project is under way in Japan to develop a high-power voltage source converter system for future dC interconnection between AC networks and HVdC transmission. A 300 MW/AC 275 kV converter transformer with series-connected line-side windings for combination of multiple voltage source PWM converters in series on the AC side is being developed. down-scaled transformer models were manufactured, and subjected to factory testing to verify the solutions for equalization of voltage sharing between the windings, prevention of dC magnetization in the core caused by the converter output voltages, and estimation of core losses when the core is magnetized by a PWM converter. Based on the design criteria confirmed by factory testing, 53 MVA GTO-based converters and converter transformers were installed for a prototype back-to-back link between actual 50 Hz/66 kV and 60 Hz/275 kV systems, and field testing is being conducted. The behavior of magnetic flux across the core during operation was monitored by embedded Hall-effect sensors. Satisfactory results were obtained.

关键词： Transformer cores Magnetic cores Pulse width modulation converters Production facilities Magnetic flux system testing Analog-digital conversion HVdC transmission Virtual manufacturing Magnetization

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dC insulating properties of newly developed XLPE cable

DC insulating properties of newly developed XLPE cable

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International Symposium on Electrical Insulating Materials

作者： T. Tanaka T. Itaya S. Katakai Y. Murata K. Takahashi Power Engineering R&D Center Tokyo Electric Power Company Inc. Yokohama Japan Power System Laboratory Hitachi Cable Limited Hitachi Japan

We have conducted a study into the application of high density polyethylene (HdPE) to dC cable insulation. HdPE has excellent electrical properties under dC voltage. However, it appeared that HdPE is very difficult to use for dC cable insulation because of a production problem where HdPE easily generates voids, in which case the insulation wall thickness increases. We studied past experimental knowledge again, and investigated the development of new dC power cable insulation.

关键词： Cable insulation Power cables Power cable insulation Stress Space charge Communication cables dielectrics and electrical insulation Polyethylene Conductivity Polymers

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INdIrECT LIGHTNING EFFECTS ON SHOrT OVErHEAd LINES

INDIRECT LIGHTNING EFFECTS ON SHORT OVERHEAD LINES

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2024 rOMA International Symposium on Electromagnetic Compatibility, EMC 1998

作者： rachidi, F. rubinstein, M. Zweiacker, P. Ianoz, M. Braendli, B. Kaelin, A. University of Toronto Dept. of Electrical and Computer Engineering Canada Montena EMC RossensCH-1728 Switzerland Swisscom R&D BernCH-3000 Switzerland Swiss Federal Institute of Technology Power Systems Laboratory LausanneCH-IOI5 Switzerland Swiss Defense Procurement Agency NEMP Labor AC Zentrum SpiezCH-3700 Switzerland

ISBN: (纸本)9798331500016

The aim of this paper is to quantify the lightning-induced distUIbances on short overhead lines. An experimental study was carried out in Camp Blanding in 1995 in which the current induced on a short structure by artificially-initiated lightning was measured. For the considered electrically-short structures, is that the induced signals can be predicted with reasonable accuracy using a simple quasistatic approach. Further experiences conducted in a high voltage laboratory allowed us to propose protective solutions. © 1998 University of rome a La Sapienza.

关键词： Overhead lines

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Indirect Lightning Effects on Short Overhead Lines

Indirect Lightning Effects on Short Overhead Lines

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EMC'98 rOMA International Symposium on Electromagnetic Compatibility

作者： F. rachidi M. rubinstein P. Zweiacker M. Ianoz B. Braendli A. Kaelin University of Toronto Dept. of Electrical and Computer Engineering Canada. Montena EMC CH-1728 Rossens Switzerland. Swisscom R&D CH-3000 Bern Switzerland. Swiss Federal Institute of Technology Power Systems Laboratory CH-1015 Lausanne Switzerland. Swiss Defense Procurement Agency NEMP Labor AC Zentrum CH-3700 Spiez Switzerland.

ISBN: (纸本)9798331500016

The aim of this paper is to quantify the lightning-induced disturbances on short overhead lines. An experimental study was carried out in Camp Blanding in 1995 in which the current induced on a short structure by artificially-initiated lightning was measured. For the considered electrically-short structures, is that the induced signals can be predicted with reasonable accuracy using a simple quasistatic approach. Further experiences conducted in a high voltage laboratory allowed us to propose protective solutions.

关键词： Lightning Current measurement Magnetic fields Telephone sets Circuits Magnetic field measurement Wire Cables Voltage measurement Protection

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dielectric breakdown of silicon oxide studied by scanning probe microscopy

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Journal of Vacuum Science & Technology B: Microelectronics Processing and Phenomena 1997年第6期15卷 1884-1884页

作者： Yasue, Takao Yoshida, Yoshiko Koyama, Hiroshi Kato, Tadao Nishioka, Tadashi ULSI R&D Laboratory Mitsubishi Electric Corporation 4-1 Mizuhara Itami Hyogo 664 Japan Ryoden Semiconductor System Engineering Corporation 4-1 Mizuhara Itami Hyogo 664 Japan

The applicability of scanning probe microscopy in the dielectric breakdown characteristics of silicon oxide has been demonstrated. Our study demonstrates that the measurement on the oxide is free from the effect of trapped charge created by Fowler–Nordheim tunneling when a sufficient distance is maintained between the measuring points. In this condition, for a 13-nm-thick oxide, the dielectric breakdown voltages were found to be so uniform as to fluctuate only 1%. We applied this method to oxides on the wafers from two different vendors, and found that the dielectric breakdown strength of the oxide depends on the difference on the Si substrates. We also applied this method to a square oxide pattern surrounded by a field oxide, and the result was that the dielectric breakdown strength of the oxide on the edge is lower than the one in the center.

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High performance 155 Mbps optical transceiver module for ATM LAN application

High performance 155 Mbps optical transceiver module for ATM...

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IEEE Photonics Conference (IPC)

作者： W.K. Kim J.H. Koh M.K. Park Y.K. Sin System IC R&D Laboratory Hyundai Electronics Industries Company Limited Ichon Gyeonggi South Korea

The optical transceiver (Trx) module is one of major components in the fiber optic network of ATM/SONET/SdH. In particular, 155 Mbps Trx modules are finding broad applications including LAN and FITL. The Trx module does both send and receive functions in a single package. In this paper, we report on high performance, compact, and cost effective Trx module useful for ATM LAN application.

关键词： Transceivers Local area networks Optical receivers Optical transmitters Circuits Power generation Packaging Quantum well lasers Welding Bit error rate

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Farming methodology for TMN platform independent class repository design

Farming methodology for TMN platform independent class repos...

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IEEE Annual International computer Software and Applications Conference (COMPSAC)

作者： Soo-Hyun Park Sang-Hoon Park doo-Kwon Baik LG R&D Complex LG Information and Communications Limited South Korea Software System LaboratoryDepartment of Computer Science Engineering Korea University South Korea

As the agents in a TMN system are constructed based on different platforms, there are some problems in the development, maintenance and administration of classes in distributed objects (dO). To solve these problems, the paper suggests the Farming methodology which originated from the network computing concept. With the methodology, redundant software and data components in the distributed objects are moved to a platform independent class repository (PICr) in the form of componentware. When the PICr is constructed, several aspects of TMN are considered. After setting up the framework of dO, some small componentwares are loaded dynamically to dO, while others are loaded statically. dOs can self-adapt componentware for the evolution of a network environment while the TMN system is running.

关键词： Hardware Chromium computer networks Telecommunication network management Intelligent networks Operating systems Software maintenance research and development Software systems computer science

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Orientation-dependent fracture strain in single-crystal silicon beams under uniaxial tensile conditions

Orientation-dependent fracture strain in single-crystal sili...

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International Symposium on Micromechatronics and Human Science (MHS)

作者： T. Ando K. Sato M. Shikida T. Yoshioka Y. Yoshikawa T. Kawabata Department of Micro System Engineering University of Nagoya Nagoya Japan Nagoya Daigaku Nagoya Aichi JP Central R&D Laboratory OMRON Corporation Japan

The proposed method for testing the uniaxial tensile characteristics of thin film materials is integrated onto a silicon chip. The developed process for fabricating the test chips starts with SOI wafers whose top silicon layer is prepared for the test materials. The results of testing single-crystal silicon films having orientations of <100>, <110>, and <111> were compared with those from bending tests of bulk silicon. The measured Young's moduli and fracture strains clearly showed orientation dependence, and the measured values were reasonable compared with those of the bulk materials. The fracture strains varied from 0.4 to 2.2% depending on the orientation and were the lowest in the <111> direction.

关键词： Tensile strain Uniaxial strain Silicon Materials testing Strain measurement Semiconductor films Semiconductor device measurement Micromechanical devices Mechanical factors Bars

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