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THE CALLING(SM) NETWORK - A GLOBAL WIRELESS COMMUNICATION-SYSTEM

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第1期12卷 45-61页

作者： TUCK, EF PATTERSON, dP STUART, JR LAWRENCE, MH Calling Communications Corporation. 1900 West Garvey Ave South. Suite 200 West Covina CA 91790 USA. Chairman of Calling Communications Corporation. He is also the Managing Director of Kinship Venture Management Inc. the general partner of Kinship Partners 11 and a General Partner of Boundary the general partner of The Boundary Fund. As a venture capitalist he has founded or participated in founding several telecommunications companies including Calling Communications Corporation Magellan Systems Corporation manufactures of Global Positioning System receivers Applied Digital Access manufacturer of DS-3 test access and network performance monitoring equipment Endgate Technology Corporation specialists in satellite phased array antennas and Poynting Systems Corporation. now a division of Reliance Corporation manufacturers of fibre optic transport equipment. He was a founder of Kebby Microwave Corporation where he invented the first solid-state. frequency-modulated commercial microwave link system. The company was acquired by ITT Corporation where he rose to the position of V.P. and Technical Director of ITT North America Telecommunications Inc. Subsequently he was V.P. of Marketing and Engineering at American Telecommunications Inc. (ATC). He was founding Director of American Telecom Inc. a joint venture between ATC and Fujitsu and has served on more than 20 boards of directors including those of three public companies. He has authored articles on microwave engineering and telephone signalling and was a contributor to Reference Data For Radio Engineers. He is a graduate of the University of Missouri at Rolla where he was later awarded an honorary Professional degree and serves on its Academy of Electrical Engineering. Mr Tuck is a Senior Member of the IEEE a Fellow of the Institution of Engineers (Australia) a Professional Member of the AIAA and a registered professional engineer in three states. More than 25 years of experience in the telecommunications industry where he has been responsibl

There is a very large demand for basic telephone service in developing nations, and remote parts of industrialized nations, which cannot be met by conventional wireline and cellular systems. This is the world's largest unserved market. We describe a system which uses recent advances in active phased arrays, fast-packet switching technology, adaptive routeing, and light spacecraft technology, in part based on the work of the Jet Propulsion Laboratory and on recently-declassified work done on the Strategic defense Initiative, to make it possible to address this market with a global telephone network based on a large low-Earth-orbit constellation of identical satellites. A telephone utility can use such a network to provide the same modern basic and enhanced telephone services offered by telephone utilities in the urban centres of fully-industrialized nations. Economies of scale permit capital and operating costs per subscriber low enough to provide a service to all subscribers, regardless of location, at prices comparable to the same services in urban areas of industrialized nations, while generating operating profits great enough to attract the capital needed for its construction. The bandwidth needed to support the capacity needed to gain these economies of scale requires that the system use K(alpha)-band frequencies. This choice of frequencies places unusual constraints on the network design, and in particular forces the use of a large number of satellites. Global demand for basic and enhanced telephone service is great enough to support at least three networks of the size described herein. The volume of advanced components, and services such as launch services, required to construct and replace these networks is sufficient to propel certain industries to market leadership positions in the early 21st Century.

关键词： LOW EARTH ORBIT SATELLITE COMMUNICATIONS FAST PACKET SWITCHING EARTH FIXEd CELLS AdAPTIVE ROUTEING LIGHT SPACECRAFT K(A) BANd phASEd-ARRAY ANTENNAS

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AN ENVIRONMENTALISTS PERSPECTIVE ON ALTERNATIVES TO PUMP ANd TREAT FOR GROUNd-WATER REMEdIATION

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GROUNd WATER MONITORING ANd REMEdIATION 1993年第4期13卷 92-94页

作者： ROSS, dL Lauren Ross is an engineer and consultant on environmental and statistical projects. She has a B.S. M.S. and Ph.D. in civil engineering. Dr. Ross has 15 years of engineering experience particularly in the design of ground water monitoring systems data analysis computer modeling and computer program development. She has also worked on non-point source pollution assessment for storm water runoff. In addition to industry and governmental clients Dr. Ross provides engineering consulting to environmental groups including Save Barton Creek Association and the SOS Coalition in Austin Texas.

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VIRTUAL PROTOTYPING USING KNOWLEdGE - BASEd MOdELING ANd SIMULATION TECHNIQUES

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NAVAL ENGINEERS JOURNAL 1993年第3期105卷 201-212页

作者： SHEA, JG The Author:holds bachelor and master of engineering degrees in mechanical engineering a M.Eng. in engineering management and is currently fulfilling requirements for the M.S. and Ph.D. degrees in computer science at the University of Louisville. He is employed as program manager Phalanx Advanced Engineering Development at the Naval Ordnance Station Crane Div. NavSurfWarCen Louisville Ky. During his tenure with Phalanx Mr. Shea has contributed to system reliability improvement system performance upgrading and the development of the Phalanx HOL (RISC) Computer. Mr. Shea is a member of ASNE the Institute of Electrical and Electronics Engineers American Institute of Aeronautics and Astronautics Society for Computer Simulation International Test & Evaluation Association and the Military Operations Research Society.

Knowledge-based modeling and simulation bridges the gap between ''conventional'' artificial intelligence implementations (such as expert systems) and more traditional computer-aided design techniques. We are currently developing software, whose primary function is to capture a user-input design specification and produce a ''virtual'' rapid prototvpe in the form of executable rule-based code. This code can then be exercised either as an interactive part of a hardware-in-the-loop testbed simulator or as a component of an object-oriented ''behavioral'' simulation environment. While the phalanx Testbed is the immediate beneficiary of this work, the techniques described have a wide range of application in the modeling of conceptual design and performance characteristics. This paper describes the system architecture and software tools that we are applying to generate virtual rapid prototypes for use in the phalanx Testbed. Particular attention is paid to defining the intelligent knowledge-capture mechanisms and model generation methodologies that we are using to translate design knowledge and performance requirements into rule-based simulations. The object-oriented programming approach to the merging of ''new'' data with previouslv-captured and stored data is discussed, and the issues of verifying and validating prototypes generated using such partiallv ''reengineered'' models are examined. An application currently in use as an investigative prototype for testbed development, a simple position controller servomechanism used to control the azimuth angle of a target-tracking sensor, is used to illustrate the process.

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SIGNALS. Interactive software for one-dimensional signal processing

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computer Applications in Engineering Education 1993年第6期1卷 489-489页

作者： Easton, R.L. Jr. Chester F. Carlson Center for Imaging Science Rochester Institute of Technology 54 Lomb Memorial Drive Rochester NY 14623-5604 Roger L. Easton Jr.:is an Assistant Professor in the Chester F. Carlson Center for Imaging Science at the Rochester Institute of Technology. He received the B.S. degree in Astronomy from Haverford College the M.S. in Physics from the University of Maryland and the M.S. and Ph.D. degrees in Optical Sciences from the University of Arizona. He is a member of SPIE OSA and IEEE. His interests include optical signal processing digital image processing in astronomy digital halftoning and computer-generated holography.

This article describes the features of a dOS program that was written for interactive demonstrations of one-dimensional (1-d) signal processing concepts in a classroom environment. It also is used to illustrate aspects of linear systems, physical optics, and complex numbers. The program is menu-driven, and experience has proven that it is easy to learn and use. Complex-valued functions are loaded from a sizeable menu of options and may be processed in a variety of ways and plotted in several formats. data files may be input from or output to other applications, e.g. spreadsheets.

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APPLICATION OF ELECTROMAGNETIC LOGGING TO CONTAMINATION INVESTIGATIONS IN GLACIAL SANd-ANd-GRAVEL AQUIFERS

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GROUNd WATER MONITORING ANd REMEdIATION 1993年第3期13卷 129-138页

作者： WILLIAMS, JH LAphAM, WW BARRINGER, TH John H. Williams received an M.S. in geology from Penn State University in 1980 and has worked for the U.S. Geological Survey since that time. He currently is the ground water specialist for the New York District (P.O. Box 1669 Albany NY 12201) and the borehole geophysics specialist for the Northeastern Region. He is also an instructor for the National Ground Water Association course on aquifer test methods. His primary interest is the application of borehole geophysics to ground water studies. Wayne W. Lapham has been employed as a hydrologist with the U.S. Geological Survey since 1976. He currently works for USGS as a ground water specialist for the National Water-Quality Assessment Program (MS 413 Reston VA 22092). He received a B.S. degree in mechanical engineering from Northeastern University in 1969 an M.S. in geology from the University of Massachusetts in 1975 and a Ph.D. in hydrology from the University of Arizona in 1988. He has been involved with various aspects of ground water hydrology including resource appraisal and ground water modeling. Thomas H. Barringer is the statistical methods specialist for the New Jersey District of the U.S. Geological Survey (810 Bear Tavern Rd West Trenton NJ 08628). His interests include spatial statistics and the application of statistical methods to hydrological problems. He has a joint M.S. in regional planning and regional science and a PhD. in regional science from the University of Pennsylvania.

Electromagnetic (EM) logging provides an efficient method for high-resolution, vertical delineation of electrically conductive contamination in glacial sand-and-gravel aquifers. EM, gamma, and lithologic logs and specific conductance data from sand-and-gravel aquifers at five sites in the northeastern United States were analyzed to define the relation of EM conductivity to aquifer lithology and water quality. Municipal waste disposal, septic waste discharge, or highway deicing salt application at these sites has caused contaminant plumes in which the dissolved solids concentration and specific conductance of ground water exceed background levels by as much as 10 to 20 times. The major hydrogeologic factors that affected EM log response at the five sites were the dissolved solids concentration of the ground water and the silt and clay content in the aquifer. EM conductivity of sand and gravel with uncontaminated water ranged from less than 5 to about 10 millisiemens per meter (mS/m);that of silt and clay zones ranged from about 15 to 45 mS/m;and that of the more highly contaminated zones in sand and gravel ranged from about 10 to more than 80 mS/m. Specific conductance of water samples from screened intervals in sand and gravel at selected monitoring well installations was significantly correlated with EM conductivity. EM logging can be used in glacial sand-and-gravel aquifer investigations to (1) determine optimum depths for the placement of monitoring well screens;(2) provide a nearly continuous vertical profile of specific conductance to complement depth-specific water quality samples;and (3) identify temporal changes in water quality through sequential logging. detailed lithologic or gamma logs, preferably both, need to be collected along with the EM logs to define zones in which elevated EM conductivity is caused by the presence of silt and clay beds rather than contamination.

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EPAS APPROACH TO VAdOSE ZONE MONITORING AT RCRA FACILITIES

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GROUNd WATER MONITORING ANd REMEdIATION 1993年第1期13卷 151-158页

作者： dURANT, Nd MYERS, VB ECCLES, LA Washington D.C. 20460) has worked as an environmental scientist in the RCRA corrective action program at EPA since 1989. After graduating from Colgate University in 1987 Durant worked for GeoTrans Inc. conducting hydrogeologic investigations at numerous waste disposal sites throughout the northeastern United States. At present Durant is pursuing an M.S. degree in environmental science from The Johns Hopkins University. His research is focused on enhancing in situ biodegradation of aromatic organic compounds in the subsurface. Washington D. C. 20460) graduated from The Johns Hopkins University in 1972 with a B.A. degree in natural sciences. Myers received a Ph.D. in oceanography from Florida State University in 1977. During 1978 he held a post doctoral fellowship at University of Florida in the Department of Environmental Engineering and Science. From 1979 to 1983 Myers was employed by the Florida Department of Environmental Regulation where he worked on environmental restoration projects. Since 1984 Myers has worked at EPA managing RCRA ground water monitoring and corrective action programs. Lawrence A. Eccles (U.S. Environmental Protection Agency Environmental Monitoring Systems Laboratory P.O. Box 93478 Las Vegas NV 89193–3478) is a hydrologist with the EPA Environmental Monitoring Systems Research Laboratory in Las Vegas Nevada. Eccles is responsible for the development of vadose zone and in situ monitoring techniques and guidelines. After graduating from Monmouth College with a B.S. degree in chemistry Eccles performed graduate work in chemical engineering at New Mexico State University. He received formal training in hydrology in 1969 from the U.S. Geological Survey in Denver and worked with that agency before joining EPA at Las Vegas in 1984. One of his co-authored articles was chosen for the Best Paper Award by the journal Ground Water in 1975 and another was the subject of a cover story for Water Well Journal in 1977.

The U.S. Environmental Protection Agency (EPA) recently proposed to amend federal regulations to require vadose zone monitoring at certain hazardous waste facilities. To support this proposal, EPA evaluated previous policy on vadose zone monitoring and examined advances in vadose zone monitoring technology. Changes in EPA vadose zone monitoring policy were driven by demonstrated advances in the available monitoring technology and improvements in understanding of vadose zone processes. When used under the appropriate conditions, currently available direct and indirect monitoring methods can effectively detect contamination that may leak from hazardous waste facilities into the vadose zone. direct techniques examined include soil-core monitoring and soil-pore liquid monitoring. Indirect techniques examined include soil-gas monitoring, neutron moderation, complex resistivity, ground-penetrating radar, and electrical resistivity. Properly designed vadose zone monitoring networks can act as a complement to saturated zone monitoring networks at numerous hazardous waste facilities. At certain facilities, particularly those in arid climates where the saturated zone is relatively deep, effective vadose zone monitoring may allow a reduction in the scope of saturated zone monitoring programs.

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CONCURRENT BOUNdARY-ELEMENT COMPUTATION

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INTERNATIONAL JOURNAL OF NUMERICAL MOdELLING-ELECTRONIC NETWORKS dEVICES ANd FIELdS 1993年第2期6卷 83-98页

作者： MCdOWALL, dS LEE, TW FUSCO, VF Microwave Research Group Department of Electrical and Electronic Engineering The Queen's University of Belfast Ashby Building Stranmillis Road Belfast BT9 5AH Northern Ireland U.K. D. Stewart McDowall was born in Dublin epublic of Ireland in 1967. He received the M. Eng. degree in Electrical and Electronic Engineering from the Queen's University of Belfast in 1990. In the same year he was presented with a Distinction Award from the Department of Education of Northern Ireland and he is currently pursuing his Ph.D. in the Microwave Research Group at Q.U.B. His principal research area is the electromagnetic field mapping of microwave systems using concurrient programming. He is an Associate Member of the Institute of Electrical Engineers. Lee Thaim Wee was awarded the degree of B. Eng. in Electronics from the Queen's University of Belfast in July 1991. He is currently serving in the Malaysian Armed Forces. Vincent F. Fusco was educated at the Queen's Univeristy of Belfast where he obtained the degree of Ph.D. in 1982. He has worked as a research engineer on short-range radar and radio telementry systems. Currently he is a reader in Microwave Communications in the School of Electrical Engineering and Computer Science the Queen's Univeristy of Belfast. His current research interests include non-linear microwave circuit simulation and concurrent programming techniques for electromagnetic field problems with particular emphasis on EMC applications. He has published numerous research papers in these areas. He is the author of the bookMicrowave Circuits Analysis and Computer Aided Design Prentice-Hall 1987. Dr Fusco is a Chartered Electrical Engineer and a Member of the Institute of Electrical Engineers.

A major limitation of the boundary element method (BEM) for the solution of electrical potential problems is the long computational time required. However, a large portion of the calculations involved can be viewed as being parallel in nature and can therefore be computed concurrently. This paper makes an effort to increase the efficiency of the BEM process using transputer-based multiprocessor computing techniques. The algorithms developed may equally well be applied to any multiprocessor system. The application selected to demonstrate the technique is the solution of an electrostatic problem governed by a two-dimensional Laplace equation. A parallel algorithm for problem setup and field extraction using BEM is designed and implemented on a transputer array. Special attention is directed to the utilization of the parallel processors to achieve maximum efficiency. The analysis in this work concentrates on the communication strategies for passing data between processors as well as a consideration of the workload attributed to each processor. The parallel algorithms were implemented using 3L Parallel Fortran;however, the choice of topology for the overall BEM implementation was limited by the fact that certain parts of the algorithm could only utilize a pipeline configuration of processors. Comprehensive results for the parallel BEM algorithm are given and they are encouraging, indicating that parallel processing has much to offer when applied to the boundary element method.

关键词： Boundary element method

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HYdROCARBON VAPOR dIFFUSION IN INTACT CORE SLEEVES

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GROUNd WATER MONITORING ANd REMEdIATION 1993年第1期13卷 139-150页

作者： OSTENdORF, dW MOYER, EE XIE, YF RAJAN, RV David W. Ostendorf (Civil Engineering Department University of Massachusetts Amherst MA 01003) is an associate professor in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst. His research interests include unconfined aquifer contamination hazardous waste site remediation and analytical modeling of problems in environmental fluid mechanics. Ostendorf is a Registered Professional Engineer in Massachusetts and a member of the American Geophysical Union American Society of Civil Engineers Soil Science Society of America Water Pollution Control Federation and Association of Environmental Engineering Professors as well as the National Ground Water Association. Ellen E. Moyer (Civil Engineering Department University of Massachusetts Amherst MA 01003) is a doctoral candidate in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst with an M.S. degree in environmental engineering from that institution. Her research interests include subsurface investigation soil venting bioremediation and analytical modeling of subsurface contamination. She has six years of professional experience managing hazardous waste site investigation and cleanup projects and is a member of the National Ground Water Association and the American Society of Civil Engineers. Yuefeng Xie (Civil Engineering Department University of Massachusetts Amherst MA 01003) is a postdoctoral research associate in the Environmental Engineering Program of the Civil Engineering Department of the University of Massachusetts at Amherst. His research interests include environmental analyses drinking water treatment and the chemical characterization and removal of disinfection by-products. A graduate with a Ph.D. and an M.S. in environmental engineering and a B.S. in chemistry and chemical engineeering from Tsinghua University Beijing China Xie is a member of the American Water Works Association and the Water Poll

The diffusion of 2,2,4-trimethylpentane (TMP) and 2,2,5-trimethylhexane (TMH) vapors out of residually contaminated sandy soil from the U.S. Environmental Protection Agency (EPA) field research site at Traverse City, Michigan, was measured and modeled. The headspace of an intact core sleeve sample was swept with nitrogen gas to simulate the diffusive release of hydrocarbon vapors from residual aviation gasoline in and immediately above the capillary fringe to a soil-venting air flow in the unsaturated zone. The resulting steady-state profile was modeled using existing diffusivity and air porosity estimates in a balance of diffusive flux and a first order source term. The source strength, which was calibrated with the observed flux of 2,2,4-TMP leaving the sleeve, varied with the residual gasoline remaining in the core, but was independent of the headspace sweep flow rate. This finding suggested that lower soil-venting air flow rates were in principle as effective as higher air flow rates in venting LNAPL vapors from contaminated soils. The saturated vapor concentration ratio of 2,2,4-TMP to 2,2,5-TMH decreased from 6.6 to 3.5 over the duration of the experiments in an expression of distillation effects. The vertical profile model was tested against sample port data in four separate experiments for both species, yielding mean errors ranging from 0 to -24 percent in magnitude.

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TLM MOdELING USING AN SIMd computer

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INTERNATIONAL JOURNAL OF NUMERICAL MOdELLING-ELECTRONIC NETWORKS dEVICES ANd FIELdS 1993年第4期6卷 299-304页

作者： TAN, CC FUSCO, VF The Queen's University of Belfast Department of Electrical & Electronic Engineering Ashby Building Stranmillis Road Belfast BT9 5AH U.K. Chun Chia Tan obtained a first-class honours degree from The Queen's University of Belfast. He was awarded an IEE prize for best final-year project. His current research interests include the modelling of electromagnetic fields using parallel processing techniques. At present Mr Tan is working as an electrical engineer in Malaysia. Vincent F. Fusco was educated at The Queen's University of Belfast where he obtained the degree of Ph.D. He has worked as a research engineer on short-range radar and radio telementry systems. Currently he is a Reader in Microwave Commnications in the School of Electrical Engineering and Computer Science The Queen's Univeristy of Belfast. His current research interests include non-linear microwave circuit simulation and concurrent programming techniques for electromagnetic field problems. He has acted as consultant to a number of major companies and has published numerous research papers in these areas. He is author of the bookMicrowave Circuits Analysis and Computer Aided Design(Prentice Hall 1987). Dr Fusco is a Chartered Electrical Engineer and a Member of the Institute of Electrical Engineers.

A major limitation of the transmission-line matrix (TLM) method used to solve Maxwell's equations is the long computation time required. The TLM scattering calculations involved can, however, be viewed as parallel in nature. This paper describes an effort to reduce computational time by using an SIMd, dAP multiprocessor computer employed to solve a two-dimensional TLM electromagnetic field formulation. A parallel algorithm based on the TLM scattering algorithm is designed and implemented using FORTRAN-PLUS Enhanced on an AMT dAP 510 machine. Here the connectivity of the dAP is exploited to simulate the intrinsic scattering behaviour on which the TLM algorithm relies. The results show that parallel processing on an SIMd machine such as the dAP is advantageous, especially for higher-order mesh sizes.

关键词： Electric lines

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Stabilizers enhancing the frequency regulation action of HVdC links supplying weak AC systems

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European Transactions on Electrical Power 1993年第3期3卷 201-212页

作者： Maris, T.I. Lygdis, A.d. Vovos, N.A. Giannakopoulos, G.B. Theodoros I. Maris (1961) received the Diploma in Electrical Engineering from the University of Patras/Greece in 1984. In 1985 he joined the Power Systems Laboratory at the Electrical Engineering Department of the University of Patras as research assistant where he is currently working for his Ph.D. degree. His area of interest is HVDC transmission. (University of Patras Dep. of Electrical Engineering Power Systems Laboratory GR-26 500 Rion. Patras/Greece T +3061/997350 Fax +3061/997362) Athanassios D. Lygdis (1954) received the Diploma in Electrical Engineering from the University of Patras/Greece in 1979. From 1979 until 1982 he worked at the Nuclear Technology Laboratory of the University of Patras as research assistant. In 1983 he joined the Power Systems Laboratory at the Electrical Engineering Department of the University of Patras as scientific collaborator. He is now working for his Ph.D. degree in this Department. His main field of interest is power transmission by HVDC systems. (University of Patras Dep. of Electrical Engineering Power Systems Labora- tory GR-26 500 Rion Patras/Greece T + 3061/997350 Fax + 3061/997361) Nickolas A. Vovos (1951) received the Diploma degree from the University of Patras/Greece the M.Sc. degree from the University of Manchester/England Institute of Science and Technology. and the Ph.D. degree from the University of Patras in 1974 1975 1978 respectively all in Electrical Engineering. In 1976 he joined the Power Systems Laboratory at the Electrical Engineering Department of the University of Patras where he is now Associate Professor. His main fields of interest are the modeiling and the transient stability study of integrated AC/DC systems. He is a member of the IEEE Power Engineering Society and CIGRE and a registered professional Engineer and member of the Technical Chamber of Greece (University of Patras Dep. of Electrical Engineering Power Systems laboratory GR-26500 Rion Patras/Greece. T +3061/997369 Fax +3061/997362) Gabriel B. Giannakopoulos (1

Power System Stabilizers (PSS) superimposed to the basic control system of an HVdC link supplying a weak AC system, in order to enhance its frequency regulation action, are proposed. To decrease the AC voltage sensitivity at the inverter side, the basic control system of the HVdC link is proposed to operate with the rectifier under Minimum Ignition Angle (MIA) control and the inverter under Constant Current (CC) control. Inputs to the PSS are the frequency and the AC voltage deviations at the inverter side and their constant parameters are calculated using modal control technique. detailed simulation results for a practical integrated AC/dC system are presented to evaluate the performance of the proposed control scheme. Copyright © 1993 John Wiley & Sons, Ltd.

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