DISCRETIZATION APPROACH USING RAY-TESTING MODEL IN PARTING LINE AND PARTING SURFACE GENERATION

Institute of Scientific and Technical Information of China (English)

HAN Jianwen; JIAN Bin; YAN Guangrong; LEI Yi

2007-01-01

Surface classification, 3D parting line, parting surface generation and demoldability analysis which is helpful to select optimal parting direction and optimal parting line are involved in automatic cavity design based on the ray-testing model. A new ray-testing approach is presented to classify the part surfaces to core/cavity surfaces and undercut surfaces by automatic identifying the visibility of surfaces. A simple, direct and efficient algorithm to identify surface visibility is developed. The algorithm is robust and adapted to rather complicated geometry, so it is valuable in computer-aided mold design systems. To validate the efficiency of the approach, an experimental program is implemented. Case studies show that the approach is practical and valuable in automatic parting line and parting surface generation.

Mini-Uav LIDAR for Power Line Inspection

Science.gov (United States)

Teng, G. E.; Zhou, M.; Li, C. R.; Wu, H. H.; Li, W.; Meng, F. R.; Zhou, C. C.; Ma, L.

2017-09-01

Light detection and ranging (LIDAR) system based on unmanned aerial vehicles (UAVs) recently are in rapid advancement, meanwhile portable and flexible mini-UAV-borne laser scanners have been a hot research field, especially for the complex terrain survey in the mountains and other areas. This study proposes a power line inspection system solution based on mini-UAV-borne LIDAR system-AOEagle, developed by Academy of Opto-Electronics, Chinese Academy of Sciences, which mounted on a Multi-rotor unmanned aerial vehicle for complex terrain survey according to real test. Furthermore, the point cloud data was explored to validate its applicability for power line inspection, in terms of corridor and line laser point clouds; deformation detection of power towers, etc. The feasibility and advantages of AOEagle have been demonstrated by the promising results based on the real-measured data in the field of power line inspection.

A review on fault classification methodologies in power transmission systems: Part-II

Directory of Open Access Journals (Sweden)

Avagaddi Prasad

2018-05-01

Full Text Available The countless extent of power systems and applications requires the improvement in suitable techniques for the fault classification in power transmission systems, to increase the efficiency of the systems and to avoid major damages. For this purpose, the technical literature proposes a large number of methods. The paper analyzes the technical literature, summarizing the most important methods that can be applied to fault classification methodologies in power transmission systems.The part 2 of the article is named “A review on fault classification methodologies in power transmission systems”. In this part 2 we discussed the advanced technologies developed by various researchers for fault classification in power transmission systems. Keywords: Transmission line protection, Protective relaying, Soft computing techniques

Active power line conditioners design, simulation and implementation for improving power quality

CERN Document Server

Revuelta, Patricio Salmeron; Litrán, Salvador Pérez

2015-01-01

Active Power Line Conditioners: Design, Simulation and Implementation for Improving Power Quality presents a rigorous theoretical and practical approach to active power line conditioners, one of the subjects of most interest in the field of power quality. Its broad approach offers a journey that will allow power engineering professionals, researchers, and graduate students to learn more about the latest landmarks on the different APLC configurations for load active compensation. By introducing the issues and equipment needs that arise when correcting the lack of power quality in power grids

Bird nesting on an Athabasca power line structure

International Nuclear Information System (INIS)

Stedwill, R.J.

1989-01-01

SaskPower has recently completed its 400 km Athabasca power line, and is evaluating the predicted environmental impact of the line on the resident population of bald eagles and other raptors. During construction of the line, five major types of impact associated with the line were addressed. Minor route adjustments were made to by-pass nests of bald eagles and osprey to minimize impact of construction on breeding. The proximity of the power line to cliff faces and the north shore of lake Athabasca was maximized, and frequency of stream crossings and proximity to rapids were minimized. Route adjustments were made to ensure that the line was at least 1.6 km from bald eagle nest sites. As structures of the main 115 kV power line allow a minimum separation between conductors and grounded spars of 1.6 m, and between conductors of 4.6 m, electrocution was not considered to be a significant risk. However, on the 25 kV power line in regions of known bald eagle activity and in close proximity to bodies of water, provision was made for special structures to allow birds to perch without danger of electrocution. It was concluded that the resident population of raptors will probably be enhanced, particularly in areas not previously utilized. 8 refs., 5 figs

On-line calculation of 3-D power distribution

International Nuclear Information System (INIS)

Park, Y. H.; In, W. K.; Park, J. R.; Lee, C. C.; Auh, G. S.

1996-01-01

The 3-D power distribution synthesis scheme was implemented in Totally Integrated Core Operation Monitoring System (TICOMS), which is under development as the next generation core monitoring system. The on-line 3-D core power distribution obtained from the measured fixed incore detector readings is used to construct the hot pin power as well as the core average axial power distribution. The core average axial power distribution and the hot pin power of TICOMS were compared with those of the current digital on-line core monitoring system, COLSS, which construct the core average axial power distribution and the pseudo hot pin power. The comparison shows that TICOMS results in the slightly more accurate core average axial power distribution and the less conservative hot pin power. Therefore, these results increased the core operating margins. In addition, the on-line 3-D power distribution is expected to be very useful for the core operation in the future

AUTOMATIC RAILWAY POWER LINE EXTRACTION USING MOBILE LASER SCANNING DATA

Directory of Open Access Journals (Sweden)

S. Zhang

2016-06-01

Full Text Available Research on power line extraction technology using mobile laser point clouds has important practical significance on railway power lines patrol work. In this paper, we presents a new method for automatic extracting railway power line from MLS (Mobile Laser Scanning data. Firstly, according to the spatial structure characteristics of power-line and trajectory, the significant data is segmented piecewise. Then, use the self-adaptive space region growing method to extract power lines parallel with rails. Finally use PCA (Principal Components Analysis combine with information entropy theory method to judge a section of the power line whether is junction or not and which type of junction it belongs to. The least squares fitting algorithm is introduced to model the power line. An evaluation of the proposed method over a complicated railway point clouds acquired by a RIEGL VMX450 MLS system shows that the proposed method is promising.

On-line Monitoring System for Power Transformers

Directory of Open Access Journals (Sweden)

Alexandru HOTEA

2016-12-01

Full Text Available Power transformers are the most important and expensive equipment from the electricity transmission system, so it is very important to know the real state of health of such equipment in every moment. De-energizing the power transformer accidentally due to internal defects can generate high costs. Annual maintenance proved to be ineffective in many cases to determine the internal condition of the equipment degradation due to faults rapidly evolving. An On-line Monitoring System for Power Transformers help real-time condition assessment and to detect errors early enough to take action to eliminate or minimize them. After abnormality detected, it is still important to perform full diagnostic tests to determine the exact condition of the equipment. On-line monitoring systems can help increase the level of availability and reliability of power transformers and lower costs of accidental interruption. This paper presents cases studies on several power transformers equipped with on-line monitoring systems from Transelectrica substation.

EVALUATING DEGREE OF ACTIVE POWER LOSSES REDUCTION IN THE ELECTRIC POWER LINES WITH REACTIVE POWER COMPENSATION

Directory of Open Access Journals (Sweden)

V. N. Radkevich

2016-01-01

Full Text Available The paper considers evaluation procedure for the degree of active power losses reduction in the power transmission lines under 1 kV and 6–10 kV of the systems of electric power supply of industrial enterprises with compensating installations mounted at the side of the customer. The capacitor installations conform to the applied voltage level and factor in dielectric losses in the capacitors. The voltage at the compensating device terminal changes from 0.95 to 1.05 of the capacitors nominal voltage. The study did not account for reactive power losses in the line, nor did it for its charge capacity, conditioned by relative shortness of the cable lines generally operating in the mains of industrial enterprises. For this reason, the quantities of reactive power being consumed and generated by the transmission line are negligible and do not significantly affect the reactive power flux. The researchers obtain functional relations that allow estimating the degree of power loss reduction in the transmission line factoring in its explicit initial data. They perform mathematical analysis of the obtained functional relations and study the function by means of derivatives. The function extremum points are found as well as the intervals of its increment and decrement. A graphical research of the obtained functional relation is performed. It is ascertained that reduction of the active power losses is contingent on the line and the capacitor-installation engineering factors, the electrical energy consumer reactive load value as well as the voltage applied to the capacitor installation. The functional relations presented in the article can be employed in scoping calculation necessary for decision making on the reactive power compensation in systems of the industrial facilities electric power supply. Their account will allow a more accurate estimate of technical and economic effect of the capacitor bank installation in the electrical mains under 1 kV and 6�

Circuit for Communication Over Power Lines

Science.gov (United States)

Krasowski, Michael J.; Prokop, Normal F.; Greer, Lawrence C., III; Nappier, Jennifer

2011-01-01

Many distributed systems share common sensors and instruments along with a common power line supplying current to the system. A communication technique and circuit has been developed that allows for the simple inclusion of an instrument, sensor, or actuator node within any system containing a common power bus. Wherever power is available, a node can be added, which can then draw power for itself, its associated sensors, and actuators from the power bus all while communicating with other nodes on the power bus. The technique modulates a DC power bus through capacitive coupling using on-off keying (OOK), and receives and demodulates the signal from the DC power bus through the same capacitive coupling. The circuit acts as serial modem for the physical power line communication. The circuit and technique can be made of commercially available components or included in an application specific integrated circuit (ASIC) design, which allows for the circuit to be included in current designs with additional circuitry or embedded into new designs. This device and technique moves computational, sensing, and actuation abilities closer to the source, and allows for the networking of multiple similar nodes to each other and to a central processor. This technique also allows for reconfigurable systems by adding or removing nodes at any time. It can do so using nothing more than the in situ power wiring of the system.

Evaluation of the Harmonic Impedance of Frydlant (Line 53 Power Network

Directory of Open Access Journals (Sweden)

Shehab Abdulwadood Ali

2013-01-01

Full Text Available The harmonic impedance of the power system is an important quantity, which describes the behaviour of the power system with the existence of different frequencies beside the fundamental. The harmonic study belongs to the most difficult part of the electrical measurements and calculations even by using computer software. The main problem accompanying the calculating methods is to obtain the exact data of the electrical network parameters or to know the exact operational status of the system. In this paper the harmonic impedance of Frydlant (line 53, 22~kV in Czech Republic power network was calculated by using a very specialized software and suitable for solving such calculations called "NetCalc. version 3.0" [1].

Modeling particle emission and power flow in pulsed-power driven, nonuniform transmission lines

Directory of Open Access Journals (Sweden)

Nichelle Bruner

2008-04-01

Full Text Available Pulsed-power driven x-ray radiographic systems are being developed to operate at higher power in an effort to increase source brightness and penetration power. Essential to the design of these systems is a thorough understanding of electron power flow in the transmission line that couples the pulsed-power driver to the load. In this paper, analytic theory and fully relativistic particle-in-cell simulations are used to model power flow in several experimental transmission-line geometries fielded on Sandia National Laboratories’ upgraded Radiographic Integrated Test Stand [IEEE Trans. Plasma Sci. 28, 1653 (2000ITPSBD0093-381310.1109/27.901250]. Good agreement with measured electrical currents is demonstrated on a shot-by-shot basis for simulations which include detailed models accounting for space-charge-limited electron emission, surface heating, and stimulated particle emission. Resonant cavity modes related to the transmission-line impedance transitions are also shown to be excited by electron power flow. These modes can drive oscillations in the output power of the system, degrading radiographic resolution.

Environmental impacts of power plants and transmission lines in power system planning

International Nuclear Information System (INIS)

Miracapillo, C.; Moreschini, G.; Rome Univ. 'La Sapienza'

1992-01-01

This paper deals with a criterion to assess the environmental impacts of power plants and transmission lines in power system planning. First, the effects of hydro-plants, thermal plants and transmission lines are reviewed. Then, a number of methods for the evaluation of the environmental impacts of civil and industrial plants are described. A new criterion is proposed to introduce the evaluation of the environmental impact and related costs into methods for power system planning. Finally, the criterion is applied to a simple case

Communication Characteristics of Faulted Overhead High Voltage Power Lines at Low Radio Frequencies

Directory of Open Access Journals (Sweden)

Nermin Suljanović

2017-11-01

Full Text Available This paper derives a model of high-voltage overhead power line under fault conditions at low radio frequencies. The derived model is essential for design of communication systems to reliably transfer information over high voltage power lines. In addition, the model can also benefit advanced systems for power-line fault detection and classification exploiting the phenomenon of changed conditions on faulted power line, resulting in change of low radio frequency signal propagation. The methodology used in the paper is based on the multiconductor system analysis and propagation of electromagnetic waves over the power lines. The model for the high voltage power line under normal operation is validated using actual measurements obtained on 400 kV power line. The proposed model of faulted power lines extends the validated power-line model under normal operation. Simulation results are provided for typical power line faults and typical fault locations. Results clearly indicate sensitivity of power-line frequency response on different fault types.

Matching problems in pulse power radial transmission lines

International Nuclear Information System (INIS)

Mittag, K.; Brandelik, A.

1984-12-01

In this report we study the power transfer from a generator along a coaxial transmission line followed by a radial transmission line into a load, which in our application is a pseudo-spark plasma of about one millimeter diameter and about 15 cm in length. First the theoretical background based on transmission line theory is described. Then numerical results are presented. The main conclusion is that when matching the pulse power generator to the pseudo-spark plasma, the effect of the impedance transformation caused by the radial transmission line has to be taken into account. The conditions to obtain an optimal match are described. (orig.) [de

Raptor nest management on power lines

Energy Technology Data Exchange (ETDEWEB)

Harness, R.E. [EDM International Inc., Fort Collins, CO (United States)

2005-07-01

Many utilities in South Africa are now implementing labor-intensive methods to combat raptor nesting on power transmission lines. Methods have typically included direct nest removal and trimming of nest materials. However, the process is often unsuccessful, and utilities are now learning to accommodate the raptor nests. This paper argued that managing nests on utility structures has solved many operational problems and has resulted in positive publicity for many line operators. Nest management options included the use of stick deflectors to prevent nest material from accumulating during initial nest construction, as well as encouraging raptors to shift their efforts to a more suitable location. Raptors will often accept alternative nesting platforms, and taller, surrogate nesting poles can be placed next to distribution line structures. Elevated platforms can also be placed on problematic distribution structures, but may result in birds coming into contact with unprotected equipment. It was concluded that a successful nest management program includes plans to make nearby lines safe for raptors and to prevent their electrocution. Providing nests with bird-friendly utility configurations can result in electric facilities enhancing wild raptor populations without impacting power reliability. 14 refs., 9 figs.

National Maglev initiative: California line electric utility power system requirements

Science.gov (United States)

Save, Phil

1994-01-01

The electrical utility power system requirements were determined for a Maglev line from San Diego to San Francisco and Sacramento with a maximum capacity of 12,000 passengers an hour in each direction at a speed of 300 miles per hour, or one train every 30 seconds in each direction. Basically the Maglev line requires one 50-MVA substation every 12.5 miles. The need for new power lines to serve these substations and their voltage levels are based not only on equipment loading criteria but also on limitations due to voltage flicker and harmonics created by the Maglev system. The resulting power system requirements and their costs depend mostly on the geographical area, urban or suburban with 'strong' power systems, or mountains and rural areas with 'weak' power systems. A reliability evaluation indicated that emergency power sources, such as a 10-MW battery at each substation, were not justified if sufficient redundancy is provided in the design of the substations and the power lines serving them. With a cost of $5.6 M per mile, the power system requirements, including the 12-kV DC cables and the inverters along the Maglev line, were found to be the second largest cost component of the Maglev system, after the cost of the guideway system ($9.1 M per mile), out of a total cost of $23 M per mile.

A Simulator of Periodically Switching Channels for Power Line Communications

Science.gov (United States)

Hayasaki, Taro; Umehara, Daisuke; Denno, Satoshi; Morikura, Masahiro

An indoor power line is one of the most attractive media for in-home networks. However, there are many technical problems for achieving in-home power line communication (PLC) with high rate and high reliability. One of such problem is the degradation in the performance of the in-home PLC caused by periodically time-varying channel responses, particularly when connecting the switching power supply equipment. We present a measurement method for power line channel responses and reveal the switching of the channel responses synchronized with power-frequency voltage when connecting switching power supply equipment in sending or receiving outlets. In this paper, we term them periodically switching channel responses. The performance of PLC adapters is seriously affected by the periodically switching channel responses. Therefore, we provide a modeling of the periodically switching channel responses by using finite impulse response (FIR) filters with a shared channel memory and construct a simulator for in-home power line channels including the periodically switching channel responses in order to evaluate the various communication systems through the power line. We present the validity of the proposed simulator through the performance evaluation of OFDM/64QAM over periodically switching channels with additive white Gaussian noise. Furthermore, we evaluate the influence of the periodically switching channel responses on the communication quality of a time-invariant modulation scheme by using the proposed simulator.

Inspection Robot Based Mobile Sensing and Power Line Tracking for Smart Grid.

Science.gov (United States)

Byambasuren, Bat-Erdene; Kim, Donghan; Oyun-Erdene, Mandakh; Bold, Chinguun; Yura, Jargalbaatar

2016-02-19

Smart sensing and power line tracking is very important in a smart grid system. Illegal electricity usage can be detected by remote current measurement on overhead power lines using an inspection robot. There is a need for accurate detection methods of illegal electricity usage. Stable and correct power line tracking is a very prominent issue. In order to correctly track and make accurate measurements, the swing path of a power line should be previously fitted and predicted by a mathematical function using an inspection robot. After this, the remote inspection robot can follow the power line and measure the current. This paper presents a new power line tracking method using parabolic and circle fitting algorithms for illegal electricity detection. We demonstrate the effectiveness of the proposed tracking method by simulation and experimental results.

Effect of power quality on windings temperature of marine induction motors. Part I: Machine model

Energy Technology Data Exchange (ETDEWEB)

Gnacinski, P. [Gdynia Maritime Univ., Dept. of Ship Electrical Power Engineering, Morska Str. 83, 81-225 Gdynia (Poland)

2009-10-15

Marine induction machines are exposed to various power quality disturbances appearing simultaneously in ship power systems: frequency and voltage rms value deviation, voltage unbalance and voltage waveform distortions. As a result, marine induction motors can be seriously overheated due to lowered supply voltage quality. Improvement of the protection of marine induction machines requires an appropriate method of power quality assessment and modification of the power quality regulations of ship classification societies. This paper presents an analytical model of an induction cage machine supplied with voltage of lowered quality, used in part II of the work (effect of power quality on windings temperature of marine induction motors. Part II. Results of investigations and recommendations for related regulations) for power quality assessment in ship power systems, and for justification of the new power quality regulations proposal. The presented model is suitable for implementation in an on-line measurement system. (author)

In-Containment Signal Conditioning and Transmission via Power Lines within High Dose Rate Areas of Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Mueller, Steffen; Weigel, Robert; Koelpin, Alexander [Institute for Electronics Engineering, University of Erlangen-Nuremberg, Cauerstr. 9, 91058 Erlangen (Germany); Dennerlein, Juergen; Janke, Iryna; Weber, Johannes [AREVA GmbH, Paul-Gossen-Str. 100, 91052 Erlangen (Germany)

2015-07-01

Signal conditioning and transmission for sensor systems and networks within the containment of nuclear power plants (NPPs) still poses a challenge to engineers, particularly in the case of equipment upgrades for existing plants, temporary measurements, decommissioning of plants, but also for new builds. This paper presents an innovative method for efficient and cost-effective instrumentation within high dose rate areas inside the containment. A transmitter-receiver topology is proposed that allows simultaneous, unidirectional point-to-point transmission of multiple sensor signals by superimposing them on existing AC or DC power supply cables using power line communication (PLC) technology. Thereby the need for costly installation of additional cables and containment penetrations is eliminated. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter is designed to operate in harsh environment within the containment during full plant operation. Hardware modularity of the transmitter allows application specific tradeoffs between redundancy and channel bandwidth. At receiver side in non-radiated areas, signals are extracted from the power line, demodulated, and provided either in analog or digital output format. Laboratory qualification tests and field test results within a boiling water reactor (BWR) are validating the proof of concept of the proposed system. (authors)

In-Containment Signal Acquisition and Data Transmission via Power Lines within High Dose Areas of Nuclear Power Plants

International Nuclear Information System (INIS)

Mueller Steffen; Wibbing Sascha; Weigel Robert; Koelpin Alexander; Dennerlein, Juergen; Janke, Iryna; Weber, Johannes

2015-01-01

Signal acquisition and data transmission for innovative sensor systems and networks inside the containment of nuclear power plants (NPPs) is still a challenge with respect to safety, performance, reliability, availability, and costs. This especially applies to equipment upgrades for existing plants, special measurements, but also for new builds. This paper presents a novel method for efficient and cost-effective sensor signal acquisition and data transmission via power lines, in order to cope with the disadvantages of common system architectures that often suffer from poor signal integrity due to raw data transmissions via long cables, huge efforts and costs for installation, and low flexibility with respect to maintenance and upgrades. A transmitter-receiver architecture is proposed that allows multiplexing of multiple sensor inputs for unidirectional point-to-point transmission by superimposing information signals on existing AC or DC supply lines, but also on active and inactive sensor wires, or spare cables, using power line communication (PLC) technology. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter hardware is designed to operate in harsh environment within the containment during full plant operation. The system's modular approach allows application specific trade-offs between redundancy and throughput regarding data transmission, as well as various sensor input front-ends which are compatible with state of the art systems. PLC technology eliminates the need for costly installation of additional cables and wall penetrations, while providing a complementary and diverse communication technology for upgrades of existing systems. At the receiver side in low dose areas, signals are extracted from the power line, demodulated, and de-multiplexed, in order to regain the original sensor signal information and provide it either in analog or digital output format. Successful laboratory qualification tests, field trails

In-Containment Signal Acquisition and Data Transmission via Power Lines within High Dose Areas of Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Mueller Steffen; Wibbing Sascha; Weigel Robert; Koelpin Alexander [Institute for Electronics Engineering, University of Erlangen-Nuremberg (Germany); Dennerlein, Juergen; Janke, Iryna; Weber, Johannes [AREVA GmbH, Paul-Gossen-Str. 100, 91052 Erlangen (Germany)

2015-07-01

Signal acquisition and data transmission for innovative sensor systems and networks inside the containment of nuclear power plants (NPPs) is still a challenge with respect to safety, performance, reliability, availability, and costs. This especially applies to equipment upgrades for existing plants, special measurements, but also for new builds. This paper presents a novel method for efficient and cost-effective sensor signal acquisition and data transmission via power lines, in order to cope with the disadvantages of common system architectures that often suffer from poor signal integrity due to raw data transmissions via long cables, huge efforts and costs for installation, and low flexibility with respect to maintenance and upgrades. A transmitter-receiver architecture is proposed that allows multiplexing of multiple sensor inputs for unidirectional point-to-point transmission by superimposing information signals on existing AC or DC supply lines, but also on active and inactive sensor wires, or spare cables, using power line communication (PLC) technology. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter hardware is designed to operate in harsh environment within the containment during full plant operation. The system's modular approach allows application specific trade-offs between redundancy and throughput regarding data transmission, as well as various sensor input front-ends which are compatible with state of the art systems. PLC technology eliminates the need for costly installation of additional cables and wall penetrations, while providing a complementary and diverse communication technology for upgrades of existing systems. At the receiver side in low dose areas, signals are extracted from the power line, demodulated, and de-multiplexed, in order to regain the original sensor signal information and provide it either in analog or digital output format. Successful laboratory qualification tests, field trails

Avian mortality rates on a power line near Kampala, Uganda

African Journals Online (AJOL)

power line carried on tall metal pylons, and a smaller 33-kV line, with three conduc- tors supported on wooden poles, ... able literature on bird mortality associated with power lines (e.g. Lehman et al. 2005,. Jenkins et al. 2010, Edison .... the conductor wires would have been hard to see. Residents reported that other birds.

Inspection Robot Based Mobile Sensing and Power Line Tracking for Smart Grid

Directory of Open Access Journals (Sweden)

Bat-erdene Byambasuren

2016-02-01

Full Text Available Smart sensing and power line tracking is very important in a smart grid system. Illegal electricity usage can be detected by remote current measurement on overhead power lines using an inspection robot. There is a need for accurate detection methods of illegal electricity usage. Stable and correct power line tracking is a very prominent issue. In order to correctly track and make accurate measurements, the swing path of a power line should be previously fitted and predicted by a mathematical function using an inspection robot. After this, the remote inspection robot can follow the power line and measure the current. This paper presents a new power line tracking method using parabolic and circle fitting algorithms for illegal electricity detection. We demonstrate the effectiveness of the proposed tracking method by simulation and experimental results.

Power Line Communications for Smart Grid Applications

Directory of Open Access Journals (Sweden)

Lars Torsten Berger

2013-01-01

Full Text Available Power line communication, that is, using the electricity infrastructure for data transmission, is experiencing a renaissance in the context of Smart Grid. Smart Grid objectives include the integration of intermittent renewable energy sources into the electricity supply chain, securing reliable electricity delivery, and using the existing electrical infrastructure more efficiently. This paper surveys power line communications (PLCs in the context of Smart Grid. The specifications G3-PLC, PRIME, HomePlug Green PHY, and HomePlug AV2, and the standards IEEE 1901/1901.2 and ITU-T G.hn/G.hnem are discussed.

Understanding broadband over power line

CERN Document Server

Held, Gilbert

2006-01-01

Understanding Broadband over Power Line explores all aspects of the emerging technology that enables electric utilities to provide support for high-speed data communications via their power infrastructure. This book examines the two methods used to connect consumers and businesses to the Internet through the utility infrastructure: the existing electrical wiring of a home or office; and a wireless local area network (WLAN) access point.Written in a practical style that can be understood by network engineers and non-technologists alike, this volume offers tutorials on electric utility infrastru

Investigation of Orthogonal Frequency Division Multiplexing Based Power Line Communication Systems

OpenAIRE

Hosseinpour, Ali

2015-01-01

Power Line Communication (PLC) has the potential to become the preferred technique for providing broadband to homes and offices with the advantage of eliminating the need for new wiring infrastructure and reducing the cost. Power line grids, however, present a hostile channel for data communication, since the fundamental purpose of the power line channel was only the transmission of electric power at 50/60 Hz frequencies. The development of PLC systems for providing broadband applications req...

Qualification of the on-line power determination of fuel elements in irradiation devices in the BR2 reactor

International Nuclear Information System (INIS)

Vermeeren, L.; Dekeyser, J.; Gouat, P.; Kalcheva, S.; Koonen, E.; Kuzminov, V.; Verwimp, A.; Weber, M.

2005-01-01

Fuel irradiation tests require an on-line monitoring of the fuel power. In the BR2 reactor, this is performed by continuously measuring the enthalpy change in the coolant of the irradiation device and complementing this information with data on power losses, heating of structure parts and spatial power profiles from mock-up test experiments and from calculations. Since a few years Monte Carlo codes (MCNP) are used, describing the BR2 core in great detail for every reactor cycle with its specific core load, yielding not only reliable relative values, but also calculated absolute local power values in agreement with data from PIE analyses. Several methods were conceived to combine the experimental and calculated data for the on-line calculation of the local linear power in the fuel elements; their internal consistency and the consistency with gamma spectroscopy data and data from radiochemical fission product analysis was checked. The data show that fuel irradiations in BR2 can be performed in a well-controlled way, with an accurate and reliable on-line follow-up of the fuel power. (author)

Focusing of cosmic radiation near power lines. A theoretical approach

International Nuclear Information System (INIS)

Skedsmo, A.; Vistnes, A.I.

1997-02-01

The purpose of this work was to determine if, and to what extent, cosmic radiation can be focused by power lines. As an alternative to experimental measurements, a computer program was developed for simulation of particle trajectories. Starting from given initial values, the cosmic particles trajectories through the electromagnetic field surrounding power lines were simulated. Particular efforts have been made to choose initial values which represent the actual physical condition of the cosmic radiation at ground level. The results show an average decrease in the particle flux density in an area below a power line and a corresponding increased flux between 12 m and 45 m on either side of the centre of the power line. The average shift in flux density is, however, extremely small (less than 0.1%) and probably not measurable with existing detector technology. 11 refs., 4 figs., 2 tabs

Electric Power Lines : Questions and Answers on Research into Health Effects.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1994-05-01

Most people know that electric power lines, like the wiring in our homes, can cause serious electric shocks if we`re not careful. Many people also want to know whether the electric and magnetic fields (EMF) produced by power lines and other electrical devices cause health effects. The purpose of this booklet is to answer some common questions that the Bonneville Power Administration (BPA) receives about the possible effects of power lines on health. First, some basic electrical terms are defined, and electric and magnetic fields are debed. Next, answers are given to several questions about recent scientific studies. Some important information about electrical safety follows. We then describe how BPA is addressing public concerns about potential health effects of power lines. The last section tells you how to obtain more detailed information about the health and safety issues summarized in this booklet.

Nonceramic insulators for the transmission power lines. Part I: Experiences of a promising technology; Aisladores no ceramicos para las lineas de transmision. Parte I: Experiencias de una tecnologia prometedora

Energy Technology Data Exchange (ETDEWEB)

Fierro Chavez, Jose Luis [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

1999-07-01

The nonceramic insulators have special characteristics that make them attractive to solve problems detected in glass or porcelain insulators, mainly in zones of high contamination and vandalism. In this first part a panorama is presented of the operative experience with nonceramic insulators for transmission power lines in different parts of the world until the beginning of the Nineties decade. The tendency in its use has increased remarkably in new transmission projects, mainly in the United States, but the operative experience shows that the selection of such insulators requires a careful analysis and of a pursuit of its behavior in the field that allows the establishments of its technical - economic advantages or disadvantages of its long term application. [Spanish] Los aisladores no ceramicos poseen caracteristicas especiales que los hacen atractivos para resolver problemas detectados en los aisladores de vidrio o porcelana, principalmente en zonas de alta contaminacion y vandalismo. En esta primera parte se presenta un panorama de la experiencia operativa con aisladores no ceramicos para las lineas de transmision en diferentes partes del mundo hasta principios de la decada de los noventa. La tendencia en su uso ha incrementado notablemente en nuevos proyectos de transmision, principalmente en los Estados Unidos, pero la experiencia operativa muestra que la seleccion de dichos aisladores requiere de un analisis cuidadoso y de un seguimiento de su comportamiento en campo que permita establecer las ventajas o desventajas tecnico - economicas de su aplicacion a largo plazo.

Study for reactive power on distribution system line B RSG-GAS

International Nuclear Information System (INIS)

Yan Bony Marsahala

2010-01-01

Study for reactive power on distribution system line B RSG-GA is already done. The study intended to evaluate how much inductive load need the reactive power (positive), how much power factor, and what will be done to increase the power factor. The reactive power is the losses power, can't be changed into energy, but it is need for transmission process and it is cause the energy losses. The loads on distribution system line B consist of induction motors which are used for primary cooling system and secondary cooling system, lift, blower on cooling tower, and air condition system. Due to the motors using, the power factor are falling down to low. By the calculation results give that the inductive loads on distribution line B are 850 KVA and these loads caused the low power factor 0.80. If we want to increase the power factor up to 0.95, it is need to install the reactive loads likes capacitor bank 250 KVAR. (author)

Limiting electric fields of HVDC overhead power lines.

Science.gov (United States)

Leitgeb, N

2014-05-01

As a consequence of the increased use of renewable energy and the now long distances between energy generation and consumption, in Europe, electric power transfer by high-voltage (HV) direct current (DC) overhead power lines gains increasing importance. Thousands of kilometers of them are going to be built within the next years. However, existing guidelines and regulations do not yet contain recommendations to limit static electric fields, which are one of the most important criteria for HVDC overhead power lines in terms of tower design, span width and ground clearance. Based on theoretical and experimental data, in this article, static electric fields associated with adverse health effects are analysed and various criteria are derived for limiting static electric field strengths.

Electric Power Lines : Questions and Answers on Research into Health Effects.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1995-06-01

Most people know that electric power lines, like the wiring in our homes, can cause serious electric shocks if we`re not careful. Many people also want to know whether the EMF (electric and magnetic fields) produced by power lines and other electrical devices affect our health. Although no adverse health effects of electric power EMF have been confirmed, there is continued scientific uncertainty about this issue. Research on EMF is ongoing throughout the world. The purpose of this booklet is to answer some common questions that the BPA (Bonneville Power Administration) receives about the possible effects of power lines on health. First, some basic electrical terms are defined, and electric and magnetic fields are debed. Next, answers are given to several questions about recent scientific studies. Some important information about electrical safety follows. We then describe how BPA is addressing public concerns about potential health effects of power lines. The last section tells you how to obtain more detailed information about the health and safety issues summarized in this booklet.

Effect of Tower Shadow and Wind Shear in a Wind Farm on AC Tie-Line Power Oscillations of Interconnected Power Systems

DEFF Research Database (Denmark)

Tan, Jin; Hu, Weihao; Wang, Xiaoru

2013-01-01

This paper describes a frequency domain approach for evaluating the impact of tower shadow and wind shear effects (TSWS) on tie-line power oscillations. A simplified frequency domain model of an interconnected power system with a wind farm is developed. The transfer function, which relates the tie......-line power variation to the mechanical power variation of a wind turbine, and the expression of the maximum magnitude of tie-line power oscillations are derived to identify the resonant condition and evaluate the potential risk. The effects of the parameters on the resonant magnitude of the tie-line power...... are also discussed. The frequency domain analysis reveals that TSWS can excite large tie-line power oscillations if the frequency of TSWS approaches the tie-line resonant frequency, especially in the case that the wind farm is integrated into a relatively small grid and the tie-line of the interconnected...

Frequency electromagnetic sounding with industrial power lines on Karelia-Kola geotraverse

Directory of Open Access Journals (Sweden)

А. Н. Шевцов

2017-04-01

Full Text Available The paper describes theory, method and first experimental results of research on the interaction between electromagnetic waves of extremely low and ultra low frequency (0.1-200 Hz, the Earth crust and ionosphere in the field of two mutually orthogonal industrial power lines, 109 and 120 km long, in the course of FENICS experiment (Fennoscandian Electrical conductivity from Natural and Induction Control Source soundings. The main focus was on the observation results along the line of Karelia-Kola geotraverse over a distance of 700 km from the source. High horizontal homogeneity of geoelectrical lithosphere section has been detected in the eastern part of the Baltic shield at depth range from 10-15 to 50-70 km. Parameters of «regular» lithosphere section have been specified to the depth of 60-70 km. As a result of inverse problem solution for the western part of Karelia and Central Finland, a zone of decreased transverse resistivity has been detected at the depth of 50-60 km, corresponding to the area, detected by seismic methods, where Moho boundary reaches the same depth.

Airborne LIDAR Power Line Classification Based on Spatial Topological Structure Characteristics

Science.gov (United States)

Wang, Y.; Chen, Q.; Li, K.; Zheng, D.; Fang, J.

2017-09-01

Automatic extraction of power lines has become a topic of great importance in airborne LiDAR data processing for transmission line management. In this paper, we present a new, fully automated and versatile framework that consists of four steps: (i) power line candidate point filtering, (ii) neighbourhood selection, (iii) feature extraction based on spatial topology, and (iv) SVM classification. In a detailed evaluation involving seven neighbourhood definitions, 26 geometric features and two datasets, we demonstrated that the use of multi-scale neighbourhoods for individual 3D points significantly improved the power line classification. Additionally, we showed that the spatial topological features may even further improve the results while reducing data processing time.

Active high-power RF pulse compression using optically switched resonant delay lines

International Nuclear Information System (INIS)

Tantawi, S.G.; Ruth, R.D.; Vlieks, A.E.

1996-11-01

The authors present the design and a proof of principle experimental results of an optically controlled high power rf pulse compression system. The design should, in principle, handle few hundreds of Megawatts of power at X-band. The system is based on the switched resonant delay line theory. It employs resonant delay lines as a means of storing rf energy. The coupling to the lines is optimized for maximum energy storage during the charging phase. To discharge the lines, a high power microwave switch increases the coupling to the lines just before the start of the output pulse. The high power microwave switch, required for this system, is realized using optical excitation of an electron-hole plasma layer on the surface of a pure silicon wafer. The switch is designed to operate in the TE 01 mode in a circular waveguide to avoid the edge effects present at the interface between the silicon wafer and the supporting waveguide; thus, enhancing its power handling capability

Analysis of Power Network for Line Reactance Variation to Improve Total Transmission Capacity

Directory of Open Access Journals (Sweden)

Ikram Ullah

2016-11-01

Full Text Available The increasing growth in power demand and the penetration of renewable distributed generations in competitive electricity market demands large and flexible capacity from the transmission grid to reduce transmission bottlenecks. The bottlenecks cause transmission congestion, reliability problems, restrict competition, and limit the maximum dispatch of low cost generations in the network. The electricity system requires efficient utilization of the current transmission capability to improve the Available Transfer Capability (ATC. To improve the ATC, power flow among the lines can be managed by using Flexible AC Transmission System (FACTS devices as power flow controllers, which alter the parameters of power lines. It is important to place FACTS devices on suitable lines to vary the reactance for improving Total Transmission Capacity (TTC of the network and provide flexibility in the power flow. In this paper a transmission network is analyzed based on line parameters variation to improve TTC of the interconnected system. Lines are selected for placing FACTS devices based on real power flow Performance Index (PI sensitivity factors. TTC is computed using the Repeated Power Flow (RPF method using the constraints of lines thermal limits, bus voltage limits and generator limits. The reactance of suitable lines, selected on the basis of PI sensitivity factors are changed to divert the power flow to other lines with enough transfer capacity available. The improvement of TTC using line reactance variation is demonstrated with three IEEE test systems with multi-area networks. The results show the variation of the selected lines’ reactance in improving TTC for all the test networks with defined contingency cases.

Contingency management of power system with Interline Power Flow Controller using Real Power Performance Index and Line Stability Index

Directory of Open Access Journals (Sweden)

Akanksha Mishra

2016-03-01

Full Text Available As a result of privatization of the electrical industry the power transmission lines have to transfer power at their maximum transmission limits because of the competitive scenario of the electrical market. Hence, secured operation of power system has become one of the most important issues of modern era. In this paper, a probability of severity based placement strategy for Interline Power Flow Controller (IPFC has been proposed based on Composite Severity Index (CSI. The composite severity index provides an exact measure of stress in the line in terms of mega watt overloading and voltage instability. IPFC is placed on the line which has the highest probability of severity during the occurrence of different outages. The IPFC has been tuned for a multi-objective function using Differential Evolution (DE and the results have been compared with genetic Algorithm (GA. To verify the proposed method, it has been tested and implemented on IEEE 14 and 57 bus systems.

Power electron beam front shortening in magnetically insulated transmission line with inner coaxial dielectric insert

International Nuclear Information System (INIS)

Galstjan, E.A.; Kazanskiy, L.N.

1995-01-01

By now the technology of high-power high-current relativistic electron beams with microsecond duration has been developed. The same technology is used in high-power electric pulse generation. However at present the high-power beams of subnanosecond duration are necessary for some investigations and applications. The maximum power parameter achieved by means of the usual technology is limited by a value in the range of 100-300 MW. For this reason a search for new ways to generate high-power REB (relativistic electron beam) is a topical problem. It is obvious that this problem may be reduced to the generation of pulses with a subnanosecond front duration. There are many methods to shorten a pulse duration to its front duration for instance, by using parts of short-circuited transmission lines

ELF field in the proximity of complex power line configuration measurement procedures

International Nuclear Information System (INIS)

Benes, M.; Comelli, M.; Villalta, R.

2006-01-01

The issue of how to measure magnetic induction fields generated by various power line configurations, when there are several power lines that run across the same exposure area, has become a matter of interest and study within the Regional Environment Protection Agency of Friuli Venezia Giulia. In classifying the various power line typologies the definition of double circuit line was given: in this instance the magnetic field is determined by knowing the electrical and geometric parameters of the line. In the case of independent lines instead, the field is undetermined. It is therefore pointed out how, in the latter case, extracting projected information from a set of measurements of the magnetic field alone is impossible. Making measurements throughout the territory of service has in several cases offered the opportunity to define standard operational procedures. (authors)

Signal Transmission on Power Lines

DEFF Research Database (Denmark)

Dalby, Arne Brejning

1997-01-01

In the analysis of power-line networks over a large frequency span, the time-domain method used in programs like EMTP (Electromagnetic Time domain Program) can not be used. A more rigorous analysis method must be employed. The correct analysis method (assuming TEM-mode propagation) for multiple....... An approximate analysis method must be usedIn this paper it is shown that an eigenvectormatrix, that is the propagation modes, can be chosen almost arbitrarily if the frequency interval of interest lies below the frequency, where the line length is about 1/3 times the wavelength for the propagation mode...... with the lowest phase velocity. The propagation constants corresponding to the chosen eigenvector matrix (the quasi modes) are found iteratively, which is a much simpler procedure than finding the eigenvalues....

Simulation of a Narrowband Power Line Communications System over Medium Voltage

Directory of Open Access Journals (Sweden)

Nikolaos Chiotellis

2016-03-01

Full Text Available Narrowband Power Line Communications (NB-PLCs are investigated as an alternative option for transferring low rate smart grid (SG data via Medium Voltage (MV power lines. In this framework, two variants of orthogonal frequency division multiplexing are examined, namely Filtered-OFDM (F-OFDM and Wavelet-OFDM (W-OFDM, in an attempt to determine which of them is capable of transmitting low rate SG data to greater distances over non-branched MV power lines. The reach of NB-PLC signals via MV power lines is estimated, taking into account the transfer function of the relevant PLC channels and noise mechanisms as well as the specific features of the two modulation options under consideration. Simulations show that NB-PLC transmission constitutes a technically feasible and economically affordable option for exchanging low rate data with remote SG nodes dispersed over the MV grid. Moreover, simulations show that F-OFDM allows low rate data transmission to considerably greater distances compared to W-OFDM.

Digital lock-in techniques for adaptive power-line interference extraction.

Science.gov (United States)

Dobrev, Dobromir; Neycheva, Tatyana; Mudrov, Nikolay

2008-07-01

This paper presents a simple digital approach for adaptive power-line (PL) or other periodic interference extraction. By means of two digital square (or sine) wave mixers, the real and imaginary parts of the interference are found, and the interference waveform is synthesized and finally subtracted. The described technique can be implemented in an open-loop architecture where the interference is synthesized as a complex sinusoid or in a closed-loop architecture for automatic phase and gain control. The same approach can be used for removal of the fundamental frequency of the PL interference as well as its higher harmonics. It is suitable for real-time operation with popular low-cost microcontrollers.

Electric Power Lines : Questions and Answers on Research into Health Effects.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1993-11-01

Most people know that electric power lines, like the wiring in our homes, can cause serious electric shocks if we`re not careful. Many people also want to know whether the electric and magnetic fields (EMF) produced by power lines and other electrical devices cause health effects. The purpose of this pamphlet is to answer some common questions that the Bonneville Power Administration (BPA) receives about the possible effects of power lines on health. (BPA is the Pacific Northwest`s Federal electric power marketing agency.) First, some basic electrical terms are defined, and electric and magnetic fields are described. Next, answers are given to several questions about recent scientific studies. We then describe how BPA is addressing public concerns raised by these studies. Some important information about electrical safety follows. The last section tells you how to obtain more detailed information about the health and safety issues summarized in this pamphlet.

Using meteorological forecasts in on-line predictions of wind power

DEFF Research Database (Denmark)

Nielsen, Torben Skov; Nielsen, Henrik Aalborg; Madsen, Henrik

1999-01-01

This report describes a model investigation into wind power prediction model as well as a tool for predicting the power production from wind turbines in an area - the Wind Power Prediction Tool (WPPT). The predictions are based on on-line measurements of power production for a selected set...

Proceedings of the 9. international symposium on power-line communications and its applications

Energy Technology Data Exchange (ETDEWEB)

Lampe, L. (comp.) [British Columbia Univ., Vancouver, BC (Canada). Dept. of Electrical and Computer Engineering

2005-07-01

The 2005 International Symposium on Power Line Communications and Its Applications (ISPLC 2005) is the leading international scientific conference on technology and applications for communication over power lines. The conference addresses the latest technological advances in power-line communications and current and future applications of power-line communication systems including broadband Internet access, indoor home networking, power-line based communications in vehicles, power-line control networks, and automatic meter reading systems. Specific conference papers included measurements, channel characterization and modeling; standards and regulations; electromagnetic compatibility; information and communication theory; modulation and error-control coding techniques; single carrier, OFDM, and spread spectrum techniques; detection, estimation, and iterative processing techniques; signal processing algorithms and devices; multiple-access techniques; modem and LSI design; networks and protocols; system architectures; automatic meter reading systems; applications and services; and, experimental systems and field trials. A total of 90 papers were featured and organized into 14 regular sessions and one poster session. Seven of these presentations have been catalogued separately for inclusion in this database. In addition to the technical program, 3 keynotes speeches and 2 panel discussions were presented and chaired by distinguished speakers and moderators. tabs., figs.

Residential mobility of populations near UK power lines and implications for childhood leukaemia

International Nuclear Information System (INIS)

Swanson, John

2013-01-01

Epidemiological studies suggest associations between childhood leukaemia and living near high-voltage power lines, but the most obvious potential causative agent, the magnetic fields produced by the power lines, is not supported by laboratory studies or a known mechanism. An alternative hypothesised explanation is if there is greater population mobility near power lines, linking to the findings of Kinlen that population mixing increases leukaemia rates. We used the names recorded in electoral registers to see whether people near power lines move house more often than the population as a whole. We did find variations, but only small ones, and not such as to support the hypothesis. (note)

On-line test of power distribution prediction system for boiling water reactors

International Nuclear Information System (INIS)

Nishizawa, Y.; Kiguchi, T.; Kobayashi, S.; Takumi, K.; Tanaka, H.; Tsutsumi, R.; Yokomi, M.

1982-01-01

A power distribution prediction system for boiling water reactors has been developed and its on-line performance test has proceeded at an operating commercial reactor. This system predicts the power distribution or thermal margin in advance of control rod operations and core flow rate change. This system consists of an on-line computer system, an operator's console with a color cathode-ray tube, and plant data input devices. The main functions of this system are present power distribution monitoring, power distribution prediction, and power-up trajectory prediction. The calculation method is based on a simplified nuclear thermal-hydraulic calculation, which is combined with a method of model identification to the actual reactor core state. It has been ascertained by the on-line test that the predicted power distribution (readings of traversing in-core probe) agrees with the measured data within 6% root-mean-square. The computing time required for one prediction calculation step is less than or equal to 1.5 min by an HIDIC-80 on-line computer

Integrated Off-Line Power Converter

DEFF Research Database (Denmark)

Fan, Lin

The miniaturization trend of industrial and consumer electronics continuously drives the demand of reductions in size, weight, and cost of power supplies. The examples of such applications considered in this research are light-emitting diode (LED) drivers for intelligent lighting systems and inte......The miniaturization trend of industrial and consumer electronics continuously drives the demand of reductions in size, weight, and cost of power supplies. The examples of such applications considered in this research are light-emitting diode (LED) drivers for intelligent lighting systems......-resistances) of these devices are jointly determined by the device, layout, package, and PCB parasitic properties. The research highly contributes to the development towards Power Supply on Chip (PwrSoC) regardless of topologies and switching technologies. First, parasitic capacitances of power semiconductors are a part...

On-line adaptive line frequency noise cancellation from a nuclear power measuring channel

Directory of Open Access Journals (Sweden)

Qadir Javed

2011-01-01

Full Text Available On-line software for adaptively canceling 50 Hz line frequency noise has been designed and tested at Pakistan Research Reactor 1. Line frequency noise causes much problem in weak signals acquisition. Sometimes this noise is so dominant that original signal is totally corrupted. Although notch filter can be used for eliminating this noise, but if signal of interest is in close vicinity of 50 Hz, then original signal is also attenuated and hence overall performance is degraded. Adaptive noise removal is a technique which could be employed for removing line frequency without degrading the desired signal. In this paper line frequency noise has been eliminated on-line from a nuclear power measuring channel. The adaptive LMS algorithm has been used to cancel 50 Hz noise. The algorithm has been implemented in labVIEW with NI 6024 data acquisition card. The quality of the acquired signal has been improved much as can be seen in experimental results.

A Measurement and Power Line Communication System Design for Renewable Smart Grids

Science.gov (United States)

Kabalci, E.; Kabalci, Y.

2013-10-01

The data communication over the electric power lines can be managed easily and economically since the grid connections are already spread around all over the world. This paper investigates the applicability of Power Line Communication (PLC) in an energy generation system that is based on photovoltaic (PV) panels with the modeling study in Matlab/Simulink. The Simulink model covers the designed PV panels, boost converter with Perturb and Observe (P&O) control algorithm, full bridge inverter, and the binary phase shift keying (BPSK) modem that is utilized to transfer the measured data over the power lines. This study proposes a novel method to use the electrical power lines not only for carrying the line voltage but also to transmit the measurements of the renewable energy generation plants. Hence, it is aimed at minimizing the additional monitoring costs such as SCADA, Ethernet-based or GSM based systems by using the proposed technique. Although this study is performed with solar power plants, the proposed model can be applied to other renewable generation systems. Consequently, the usage of the proposed technique instead of SCADA or Ethernet-based systems eliminates additional monitoring costs.

Opportunistic replacement of fusion power system parts

International Nuclear Information System (INIS)

Day, J.A.; George, L.L.

1981-01-01

This paper describes a maintenance problem in a fusion power plant. The problem is to specify which life limited parts should be replaced when there is an opportunity. The objective is to minimize the cost rate of replacement parts and of maintenance actions while satisfying a power plant availability constraint. The maintenance policy is to look ahead and replace all parts that will reach their life limits within a time called a screen. Longer screens yield greater system availabilities because more parts are replaced prior to their life limits

Comparison of electric field exposure measurement methods under power lines

International Nuclear Information System (INIS)

Korpinen, L.; Kuisti, H.; Tarao, H.; Paeaekkoenen, R.; Elovaara, J.

2014-01-01

The object of the study was to investigate extremely low frequency (ELF) electric field exposure measurement methods under power lines. The authors compared two different methods under power lines: in Method A, the sensor was placed on a tripod; and Method B required the measurer to hold the meter horizontally so that the distance from him/her was at least 1.5 m. The study includes 20 measurements in three places under 400 kV power lines. The authors used two commercial three-axis meters, EFA-3 and EFA-300. In statistical analyses, they did not find significant differences between Methods A and B. However, in the future, it is important to take into account that measurement methods can, in some cases, influence ELF electric field measurement results, and it is important to report the methods used so that it is possible to repeat the measurements. (authors)

Detection of the power lines in UAV remote sensed images using spectral-spatial methods.

Science.gov (United States)

Bhola, Rishav; Krishna, Nandigam Hari; Ramesh, K N; Senthilnath, J; Anand, Gautham

2018-01-15

In this paper, detection of the power lines on images acquired by Unmanned Aerial Vehicle (UAV) based remote sensing is carried out using spectral-spatial methods. Spectral clustering was performed using Kmeans and Expectation Maximization (EM) algorithm to classify the pixels into the power lines and non-power lines. The spectral clustering methods used in this study are parametric in nature, to automate the number of clusters Davies-Bouldin index (DBI) is used. The UAV remote sensed image is clustered into the number of clusters determined by DBI. The k clustered image is merged into 2 clusters (power lines and non-power lines). Further, spatial segmentation was performed using morphological and geometric operations, to eliminate the non-power line regions. In this study, UAV images acquired at different altitudes and angles were analyzed to validate the robustness of the proposed method. It was observed that the EM with spatial segmentation (EM-Seg) performed better than the Kmeans with spatial segmentation (Kmeans-Seg) on most of the UAV images. Copyright © 2017 Elsevier Ltd. All rights reserved.

Proximity effects of high voltage electric power transmission lines on ...

African Journals Online (AJOL)

Yomi

2010-08-18

Aug 18, 2010 ... transmission lines on ornamental plant growth. Zeki Demir ... The effects of proximity to power-line on specific leaf area and seedling dbh were tested .... during vegetation season is about 72% and common wind blow.

(Hydro-Quebec) Illustrated vocabulary representing power line transmission and distribution of electric power. 4, maintenance. (Hydro-Quebec) Vocabulaire illustre des lignes aeriennes de transport et de distribution d'electricite. Fascicule 4, entretien

Energy Technology Data Exchange (ETDEWEB)

1986-01-01

This dictionary is intended to help standardize the terminology used among Hydro-Quebec personnel involved with power lines. This volume is concerned with words applicable to power line maintenance, and is arranged in six parts: poles and link sticks, adapters and related tools, safety devices, safety clothing and climbing equipment, measurement and control devices, and techniques. Virtually all of the terms are illustrated. English language equivalents are given, but these are not standardized terms and are included for informative purposes only. English and French indexes are included. 184 refs., 256 figs.

Fast wave power flow along SOL field lines in NSTX

Science.gov (United States)

Perkins, R. J.; Bell, R. E.; Diallo, A.; Gerhardt, S.; Hosea, J. C.; Jaworski, M. A.; Leblanc, B. P.; Kramer, G. J.; Phillips, C. K.; Roquemore, L.; Taylor, G.; Wilson, J. R.; Ahn, J.-W.; Gray, T. K.; Green, D. L.; McLean, A.; Maingi, R.; Ryan, P. M.; Jaeger, E. F.; Sabbagh, S.

2012-10-01

On NSTX, a major loss of high-harmonic fast wave (HHFW) power can occur along open field lines passing in front of the antenna over the width of the scrape-off layer (SOL). Up to 60% of the RF power can be lost and at least partially deposited in bright spirals on the divertor floor and ceiling [1,2]. The flow of HHFW power from the antenna region to the divertor is mostly aligned along the SOL magnetic field [3], which explains the pattern of heat deposition as measured with infrared (IR) cameras. By tracing field lines from the divertor back to the midplane, the IR data can be used to estimate the profile of HHFW power coupled to SOL field lines. We hypothesize that surface waves are being excited in the SOL, and these results should benchmark advanced simulations of the RF power deposition in the SOL (e.g., [4]). Minimizing this loss is critical optimal high-power long-pulse ICRF heating on ITER while guarding against excessive divertor erosion.[4pt] [1] J.C. Hosea et al., AIP Conf Proceedings 1187 (2009) 105. [0pt] [2] G. Taylor et al., Phys. Plasmas 17 (2010) 056114. [0pt] [3] R.J. Perkins et al., to appear in Phys. Rev. Lett. [0pt] [4] D.L. Green et al., Phys. Rev. Lett. 107 (2011) 145001.

Fast-wave power flow along SOL field lines in NSTX and the associated power deposition profile across the SOL in front of the antenna

International Nuclear Information System (INIS)

Perkins, R.J.; Bell, R.E.; Diallo, A.; Gerhardt, S.; Hosea, J.C.; Jaworski, M.A.; LeBlanc, B.P.; Kramer, G.J.; Maingi, R.; Phillips, C.K.; Podestà, M.; Roquemore, L.; Scotti, F.; Ahn, J.-W.; Gray, T.K.; Green, D.L.; McLean, A.; Ryan, P.M.; Jaeger, E.F.; Sabbagh, S.

2013-01-01

Fast-wave heating and current drive efficiencies can be reduced by a number of processes in the vicinity of the antenna and in the scrape-off layer (SOL). On NSTX from around 25% to more than 60% of the high-harmonic fast-wave power can be lost to the SOL regions, and a large part of this lost power flows along SOL magnetic field lines and is deposited in bright spirals on the divertor floor and ceiling. We show that field-line mapping matches the location of heat deposition on the lower divertor, albeit with a portion of the heat outside of the predictions. The field-line mapping can then be used to partially reconstruct the profile of lost fast-wave power at the midplane in front of the antenna, and the losses peak close to the last closed flux surface as well as the antenna. This profile suggests a radial standing-wave pattern formed by fast-wave propagation in the SOL, and this hypothesis will be tested on NSTX-U. RF codes must reproduce these results so that such codes can be used to understand this edge loss and to minimize RF heat deposition and erosion in the divertor region on ITER. (paper)

Line Capacity Expansion and Transmission Switching in Power Systems With Large-Scale Wind Power

DEFF Research Database (Denmark)

Villumsen, Jonas Christoffer; Bronmo, Geir; Philpott, Andy B.

2013-01-01

In 2020 electricity production from wind power should constitute nearly 50% of electricity demand in Denmark. In this paper we look at optimal expansion of the transmission network in order to integrate 50% wind power in the system, while minimizing total fixed investment cost and expected cost...... of power generation. We allow for active switching of transmission elements to reduce congestion effects caused by Kirchhoff's voltage law. Results show that actively switching transmission lines may yield a better utilization of transmission networks with large-scale wind power and increase wind power...

Environmental impact of the aerial power transmission lines

International Nuclear Information System (INIS)

Cristescu, D.; Rusan, R.

1993-01-01

In the last 10-12 years the existence of the high voltage lines existence within populated areas has been more and more contested. The paper tries to complete a blank in the Romanian technical literature by introducing the concept of 'line corridor' which is different from the occupied geometric area and from 'the line disturbed corridor'. The concept is meant to specify the area where the high frequency and 50 Hz electromagnetic pollution exceeds some given limits. The impact of the power transmission lines on the human body, due to the effects of the electric and magnetic fields, is considered. Also, the aspects concerning the visual impact, the acoustic and radio noise and the area expensing by the high voltage lines, are considered. International standards and regulations regarding the limitations of this effects are presented. (author)

Aerodynamic instability of cables in transmission power lines; Inestabilidad aerodinamica en cables de lineas de transmision

Energy Technology Data Exchange (ETDEWEB)

Lopez Lopez, Alberto; Vilar Rojas, Jorge Ivan; Munoz Black, Celso J. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1995-12-31

One of the aerodynamic instabilities of transmission power lines cables is galloping, which consists in the appearance of important cable vibrations, mainly when the wind hits orthogonally the power line. In some cases the maximum amplitude that occurs reaches several meters, even when the wind velocities in a region are well below the value used for the mechanical design of the power lines. In general terms, galloping is associated with particular climatic conditions such as low temperatures and high humidities. In these conditions a coating of ice that adheres to the cable is formed, changing its transverse cross section, propitiating the galloping, although some authors have reported galloping without ice. These climatic conditions are presented mainly in the Northern part of our country and in the high regions of the mountain zones; nevertheless, the galloping phenomenon has been reported in few cases by Comision Federal de Electricidad (CFE). The possible expansion of the power lines in these regions of the country leads to prevent the measures needed to diminish the appearance of this phenomenon. In this paper mention is made in particular of the solution adopted to the galloping problem that has appeared in the transmission power line of Salamayuca to Reforma, Ciudad Juarez, Chihuahua (CFE,1991). [Espanol] Una de las inestabilidades aerodinamicas que se presentan en los cables de lineas de transmision es el galopeo, el cual consiste en la aparicion de vibraciones importantes de los cables, sobre todo cuando el flujo del viento incide ortogonalmente a la linea. En algunos casos las amplitudes maximas que se presentan llegan a ser de varios metros, aun cuando las velocidades del viento en una region esten muy por debajo del valor empleado para el diseno mecanico de las lineas. Generalmente, el galopeo se asocia con condiciones climaticas particulares como son las bajas temperaturas y altas humedades. En estas condiciones se forma una cubierta de hielo que se

Aerodynamic instability of cables in transmission power lines; Inestabilidad aerodinamica en cables de lineas de transmision

Energy Technology Data Exchange (ETDEWEB)

Lopez Lopez, Alberto; Vilar Rojas, Jorge Ivan; Munoz Black, Celso J [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1996-12-31

One of the aerodynamic instabilities of transmission power lines cables is galloping, which consists in the appearance of important cable vibrations, mainly when the wind hits orthogonally the power line. In some cases the maximum amplitude that occurs reaches several meters, even when the wind velocities in a region are well below the value used for the mechanical design of the power lines. In general terms, galloping is associated with particular climatic conditions such as low temperatures and high humidities. In these conditions a coating of ice that adheres to the cable is formed, changing its transverse cross section, propitiating the galloping, although some authors have reported galloping without ice. These climatic conditions are presented mainly in the Northern part of our country and in the high regions of the mountain zones; nevertheless, the galloping phenomenon has been reported in few cases by Comision Federal de Electricidad (CFE). The possible expansion of the power lines in these regions of the country leads to prevent the measures needed to diminish the appearance of this phenomenon. In this paper mention is made in particular of the solution adopted to the galloping problem that has appeared in the transmission power line of Salamayuca to Reforma, Ciudad Juarez, Chihuahua (CFE,1991). [Espanol] Una de las inestabilidades aerodinamicas que se presentan en los cables de lineas de transmision es el galopeo, el cual consiste en la aparicion de vibraciones importantes de los cables, sobre todo cuando el flujo del viento incide ortogonalmente a la linea. En algunos casos las amplitudes maximas que se presentan llegan a ser de varios metros, aun cuando las velocidades del viento en una region esten muy por debajo del valor empleado para el diseno mecanico de las lineas. Generalmente, el galopeo se asocia con condiciones climaticas particulares como son las bajas temperaturas y altas humedades. En estas condiciones se forma una cubierta de hielo que se

The Evaluation Method of the Lightning Strike on Transmission Lines Aiming at Power Grid Reliability

Science.gov (United States)

Wen, Jianfeng; Wu, Jianwei; Huang, Liandong; Geng, Yinan; Yu, zhanqing

2018-01-01

Lightning protection of power system focuses on reducing the flashover rate, only distinguishing by the voltage level, without considering the functional differences between the transmission lines, and being lack of analysis the effect on the reliability of power grid. This will lead lightning protection design of general transmission lines is surplus but insufficient for key lines. In order to solve this problem, the analysis method of lightning striking on transmission lines for power grid reliability is given. Full wave process theory is used to analyze the lightning back striking; the leader propagation model is used to describe the process of shielding failure of transmission lines. The index of power grid reliability is introduced and the effect of transmission line fault on the reliability of power system is discussed in detail.

On-line reconstruction of in-core power distribution by harmonics expansion method

International Nuclear Information System (INIS)

Wang Changhui; Wu Hongchun; Cao Liangzhi; Yang Ping

2011-01-01

Highlights: → A harmonics expansion method for the on-line in-core power reconstruction is proposed. → A harmonics data library is pre-generated off-line and a code named COMS is developed. → Numerical results show that the maximum relative error of the reconstruction is less than 5.5%. → This method has a high computational speed compared to traditional methods. - Abstract: Fixed in-core detectors are most suitable in real-time response to in-core power distributions in pressurized water reactors (PWRs). In this paper, a harmonics expansion method is used to reconstruct the in-core power distribution of a PWR on-line. In this method, the in-core power distribution is expanded by the harmonics of one reference case. The expansion coefficients are calculated using signals provided by fixed in-core detectors. To conserve computing time and improve reconstruction precision, a harmonics data library containing the harmonics of different reference cases is constructed. Upon reconstruction of the in-core power distribution on-line, the two closest reference cases are searched from the harmonics data library to produce expanded harmonics by interpolation. The Unit 1 reactor of DayaBay Nuclear Power Plant (DayaBay NPP) in China is considered for verification. The maximum relative error between the measurement and reconstruction results is less than 5.5%, and the computing time is about 0.53 s for a single reconstruction, indicating that this method is suitable for the on-line monitoring of PWRs.

Optimal design and routing of power lines; ecological, technical and economic perspectives (OPTIPOL). Progress report 2012

Energy Technology Data Exchange (ETDEWEB)

Bevanger, Kjetil; Bartzke, Gundula; Broeseth, Henrik; Dahl, Espen Lie; Gjershaug, Jan Ove; Hanssen, Frank; Jacobsen, Karl-Otto; Kleven, Oddmund; Kvaloey, Paal; May, Roel; Meaas, Roger; Nygaaard, Torgeir; Resnaes, Steinar; Stokke, Sigbjoern; Thomassen, Joern

2012-07-01

WP1 'Power line ROW as habitat resources for moose (Alces alces) and other wildlife', has focused on moose browsing in power-line corridors in relation to adjacent areas in Bangdalen. Browsing surveys and pellets-group counts were also carried out in 2012 for this purpose and close to 200 plots were surveyed. A preliminary analysis of these data has been finalized. The paper: 'Comparative effects of power lines and roads and moose (Alces alces) habitat selection', was presented and submitted as contributions to the conference report at 'The 10th ROW Conference' in Arizona. WP2 'Capercaillie and black grouse population responses to power-line induced mortality', has continued the data collection in Ogndalen also in 2012. As by January 2013 a total a total of 29 search patrols have been conducted and 50 locations with birds or bird remains from collision victims in the study period were recorded. The DNA analysis has identified 7 capercaillie and 5 black grouse among these birds and birds remains. Collision mortality rate varies between years and species, where capercaillie seems more exposed than black grouse. An oral presentation, 'Black grouse and Capercaillie mortality and population Estimates by DNA identification' - was presented and consequently submitted as proceedings paper at the 10th ROW in Arizona. In WP3 'Bird collision hot spots' available data from earlier projects has been digitized and stored in a database. Some power line sections from previous projects has proven to be digitized and it is used resources to collect missing data. Database, ie GPS positions of all dead birds recorded as collision victims in relation to earlier projects, and they patrolled the power line sections, is now ready for analysis. WP4 - 'National Database for reporting dead birds, is operational and is included as part of the Biodiversity Information collection system. All data is publicly available. At the beginning of the november 2012 was added to 379 observations of dead

Residential Distance to High-voltage Power Lines and Risk of Neurodegenerative Diseases

DEFF Research Database (Denmark)

Frei, Patrizia; Poulsen, Aslak Harbo; Mezei, Gabor

2013-01-01

period 5-20 years before diagnosis were computed. The risks for developing dementia, Parkinson's disease, multiple sclerosis, and motor neuron disease were not increased in persons living within close vicinity of a power line. The risk of Alzheimer's disease was not increased for ever living within 50 m...... of a power line (hazard ratio = 1.04, 95% confidence interval: 0.69, 1.56). No dose-response according to number of years of living within 50 m of a power line was observed, but there were weak indications of an increased risk for persons diagnosed by the age of 75 years. Overall, there was little support...

Power flow studies of magnetically insulated lines

International Nuclear Information System (INIS)

McDaniel, D.H.; Poukey, J.W.; Bergeron, K.D.; VanDevender, J.P.; Johnson, D.L.

1977-01-01

The designs for relativistic electron beam accelerators with power levels of 20 to 100 TW are greatly restricted by the inductance of a single diode of reasonable size. This fact leads to modular designs of very large accelerators. One concept uses several small insulators at a large radius arranged around the accelerator center. The total effective inductance is then low, but the energy must then be transported by self-magnetic insulated vacuum lines to the target volume. A triplate vacuum line configuration eases many mechanical support problems and allows more A-K gaps or feeds to be packaged around a given radius. This type of vacuum transmission line was chosen for initial experiments at Sandia. The experiments were conducted on the MITE (Magnetically Insulated Transmission Experiment) accelerator. The water pulse forming lines are connected to a vacuum triplate line through a conventional stacked insulator. Diagnostics on the experiment consisted of: (1) input V; (2) input I; (3) I monitors at the input, middle, and output of both the center conductor and ground plane of the transmission line; (4) magnetic energy analyzer to view peak electron energy in the A-K gap; (5) calorimetry; and (6) Faraday cups to look at electron current flowing across the transmission line. The main goal of the experiment is to obtain input impedance of the transmission line as a function of voltage and to measure electron loss currents. These measurements are compared to theoretical models for the input impedance and energy losses

Multi-Mode Operation for On-line Uninterruptible Power Supply System

DEFF Research Database (Denmark)

Lu, Jinghang; Savaghebi, Mehdi; Golestan, Saeed

2018-01-01

To enhance the robustness and disturbance rejection ability of an on-line uninterruptible power supply (UPS) system, an Internal Model Control (IMC)-based DC-link voltage regulation method is proposed in this paper. Furthermore, the multi-mode operations of the on-line UPS system are investigated...

Power-line electrocution of birds (Electrocucion de Aves en Lineas Electricas en Mexico)

Science.gov (United States)

Patricia Manzano Fischer

2006-01-01

A result of rapid growth in human population and energy use, is proliferating power lines that electrocute birds, killing eagles and causing power outages. The United States was one of the first countries to recognize the significance of this problem. Suggested Practices for the Protection of Raptors on Power Lines, first published in the 1970s, has now been translated...

Proximity to overhead power lines and childhood leukaemia

DEFF Research Database (Denmark)

Amoon, Aryana T; Crespi, Catherine M; Ahlbom, Anders

2018-01-01

BACKGROUND: Although studies have consistently found an association between childhood leukaemia risk and magnetic fields, the associations between childhood leukaemia and distance to overhead power lines have been inconsistent. We pooled data from multiple studies to assess the association with d...

Safe and easy power injection of contrast material through a central line

International Nuclear Information System (INIS)

Rogalla, P.; Meiri, N.; Hamm, M.B.; Thoeni, R.F.; Goldberg, H.I.

1998-01-01

Power-assisted injection of contrast material into an antecubital vein is commonly used in CT and has been proven superior to manual injection. Power-assisted injection through a central line bares the risk of rupturing the line because manual control over the pressure applied by the power injector is lacking. We present a simple safety device which allows manual control of the pressure by means of an interposed three-way stopcock combined with a small syringe for pressure equalization. (orig.)

CALCULATION METHOD OF ELECTRIC POWER LINES MAGNETIC FIELD STRENGTH BASED ON CYLINDRICAL SPATIAL HARMONICS

Directory of Open Access Journals (Sweden)

A.V. Erisov

2016-05-01

Full Text Available Purpose. Simplification of accounting ratio to determine the magnetic field strength of electric power lines, and assessment of their environmental safety. Methodology. Description of the transmission lines of the magnetic field by using techniques of spatial harmonic analysis in the cylindrical coordinate system is carried out. Results. For engineering calculations of electric power lines magnetic field with sufficient accuracy describes their first spatial harmonic magnetic field. Originality. Substantial simplification of the definition of the impact of the construction of transmission line poles on the value of its magnetic field and the bands of land alienation sizes. Practical value. The environmentally friendly projection electric power lines on the level of the magnetic field.

Coal-fired power materials - Part II

Energy Technology Data Exchange (ETDEWEB)

Viswanathan, V.; Purgert, R.; Rawls, P. [Electric Power Research Institute, Palo Alto, CA (United States)

2008-09-15

Part 1 discussed some general consideration in selection of alloys for advanced ultra supercritical (USC) coal-fired power plant boilers. This second part covers results reported by the US project consortium, which has extensively evaluated the steamside oxidation, fireside corrosion, and fabricability of the alloys selected for USC plants. 3 figs.

Losses at magnetic nulls in pulsed-power transmission line systems

International Nuclear Information System (INIS)

Mendel, C.W. Jr.; Pointon, T.D.; Savage, M.E.; Seidel, D.B.; Magne, I.; Vezinet, R.

2006-01-01

Pulsed-power systems operating in the terawatt regime must deal with large electron flows in vacuum transmission lines. In most parts of these transmission lines the electrons are constrained by the self-magnetic field to flow parallel to the conductors. In very low impedance systems, such as those used to drive Z-pinch radiation sources, the currents from multiple transmission lines are added together. This addition necessarily involves magnetic nulls that connect the positive and negative electrodes. The resultant local loss of magnetic insulation results in electron losses at the anode in the vicinity of the nulls. The lost current due to the magnetic null might or might not be appreciable. In some cases the lost current due to the null is not large, but is spatially localized, and may create a gas and plasma release from the anode that can lead to an excessive loss, and possibly to catastrophic damage to the hardware. In this paper we describe an analytic model that uses one geometric parameter (aside from straightforward hardware size measurements) that determines the loss to the anode, and the extent of the loss region when the driving source and load are known. The parameter can be calculated in terms of the magnetic field in the region of the null calculated when no electron flow is present. The model is compared to some experimental data, and to simulations of several different hardware geometries, including some cases with multiple nulls, and unbalanced feeds

An ultra low-power off-line APDM-based switchmode power supply with very high conversion efficiency

DEFF Research Database (Denmark)

Nielsen, Nils

2001-01-01

This article describes the results from the research work on design of a ultra low power off-line power supply with very high conversion efficiency. The input voltage is 230 VAC nominal and output voltage is 5 VDC. By ultra low power levels, an output power level in the area ranging from 50 m......W and up to 1000 mW is meant. The small power supply is intended for use as a standby power supply in mains operated equipment, which requires a small amount of power in standby mode....

Implementation of the frequency dependent line model in a real-time power system simulator

Directory of Open Access Journals (Sweden)

Reynaldo Iracheta-Cortez

2017-09-01

Full Text Available In this paper is described the implementation of the frequency-dependent line model (FD-Line in a real-time digital power system simulator. The main goal with such development is to describe a general procedure to incorporate new realistic models of power system components in modern real-time simulators based on the Electromagnetic Transients Program (EMTP. In this procedure are described, firstly, the steps to obtain the time domain solution of the differential equations that models the electromagnetic behavior in multi-phase transmission lines with frequency dependent parameters. After, the algorithmic solution of the FD-Line model is implemented in Simulink environment, through an S-function programmed in C language, for running off-line simulations of electromagnetic transients. This implementation allows the free assembling of the FD Line model with any element of the Power System Blockset library and also, it can be used to build any network topology. The main advantage of having a power network built in Simulink is that can be executed in real-time by means of the commercial eMEGAsim simulator. Finally, several simulation cases are presented to validate the accuracy and the real-time performance of the FD-Line model.

K-Line Patterns’ Predictive Power Analysis Using the Methods of Similarity Match and Clustering

Directory of Open Access Journals (Sweden)

Lv Tao

2017-01-01

Full Text Available Stock price prediction based on K-line patterns is the essence of candlestick technical analysis. However, there are some disputes on whether the K-line patterns have predictive power in academia. To help resolve the debate, this paper uses the data mining methods of pattern recognition, pattern clustering, and pattern knowledge mining to research the predictive power of K-line patterns. The similarity match model and nearest neighbor-clustering algorithm are proposed for solving the problem of similarity match and clustering of K-line series, respectively. The experiment includes testing the predictive power of the Three Inside Up pattern and Three Inside Down pattern with the testing dataset of the K-line series data of Shanghai 180 index component stocks over the latest 10 years. Experimental results show that (1 the predictive power of a pattern varies a great deal for different shapes and (2 each of the existing K-line patterns requires further classification based on the shape feature for improving the prediction performance.

High power RF transmission line component development

International Nuclear Information System (INIS)

Hong, B. G.; Hwang, C. K.; Bae, Y. D.; Yoon, J. S.; Wang, S. J.; Gu, S. H.; Yang, J. R.; Hahm, Y. S.; Oh, G. S.; Lee, J. R.; Lee, W. I.; Park, S. H.; Kang, M. S.; Oh, S. H.; Lee, W.I.

1999-12-01

We developed the liquid stub and phase shifter which are the key high RF power transmission line components. They show reliable operation characteristics and increased insulation capability, and reduced the size by using liquid (silicon oil, dielectric constant ε=2.72) instead of gas for insulating dielectric material. They do not have finger stock for the electric contact so the local temperature rise due to irregular contact and RF breakdown due to scratch in conductor are prevented. They can be utilized in broadcasting, radar facility which require high RF power transmission. Moreover, they are key components in RF heating system for fusion reactor. (author)

High power RF transmission line component development

Energy Technology Data Exchange (ETDEWEB)

Hong, B. G.; Hwang, C. K.; Bae, Y. D.; Yoon, J. S.; Wang, S. J.; Gu, S. H.; Yang, J. R.; Hahm, Y. S.; Oh, G. S.; Lee, J. R.; Lee, W. I.; Park, S. H.; Kang, M. S.; Oh, S. H.; Lee, W.I

1999-12-01

We developed the liquid stub and phase shifter which are the key high RF power transmission line components. They show reliable operation characteristics and increased insulation capability, and reduced the size by using liquid (silicon oil, dielectric constant {epsilon}=2.72) instead of gas for insulating dielectric material. They do not have finger stock for the electric contact so the local temperature rise due to irregular contact and RF breakdown due to scratch in conductor are prevented. They can be utilized in broadcasting, radar facility which require high RF power transmission. Moreover, they are key components in RF heating system for fusion reactor. (author)

Advanced power cycling test for power module with on-line on-state VCE measurement

DEFF Research Database (Denmark)

Choi, Ui-min; Trintis, Ionut; Blaabjerg, Frede

2015-01-01

module. The proposed concept can perform various stress conditions which is valid in a real mission profile and it is using a real power converter application with small loss. The concept of the proposed test setup is first presented. Then, the on-line on-state collector-emitter voltage VCE measurement......Recent research has made an effort to improve the reliability of power electronic systems to comply with more stringent constraints on cost, safety, predicted lifetime and availability in many applications. For this, studies about failure mechanisms of power electronic components and lifetime...... estimation of power semiconductor devices and capacitors have been done. Accelerated power cycling test is one of the common tests to assess the power device module and develop the lifetime model considering the physics of failure. In this paper, a new advanced power cycling test setup is proposed for power...

Transmission Characteristics of an OFDM signal for Power Line Communication System with High Bit Rate

Science.gov (United States)

Mori, Akira; Watanabe, Yosuke; Tokuda, Masamitsu; Kawamoto, Koji

In this paper, we measured what influence the sinusoidal transmission characteristics of the electric power line with various forms gave to the transmission characteristic of OFDM (Orthogonal Frequency Division Multiplexing) signal through PLC (power line communication system) modem. We classified the electric power line transmission line with various forms in a real environment into two basic elements, which are an outlet type branch and a switch type branch. Next, PHY rate (Physical rate) is measured for each basic element connected with the PLC modem. At this time, the transmission characteristics of the electric power line are simulated from measured data. OFDM sending and receiving systems are composed on the computer, and the PHY rate is simulated. By comparing with measured and calculated values, it is revealed that PHY rate of PLC modem is most affected in the case of the power line transmission characteristics having broad band and high level attenuation and group delay variation, and is not affected in the case of that having narrow band attenuation and group delay variation.

Optimal design and routing of power lines; ecological, technical and economic perspectives (OPTIPOL)

Energy Technology Data Exchange (ETDEWEB)

Bevanger, K.; Bartzke, G.; Broeseth, H.; Gjershaug, J.O.; Hanssen, F.; Jacobsen, K.-O.; Kvaloey, P.; May, R.; Meaas, R.; Nygaard, T.; Refsnaes, S.; Stokke, S.; Vang, R.

2010-12-15

The OPTIPOL project - 'Optimal design and routing of power lines; ecological, technical and economic perspectives' - has been active for two years, although the main operational phase was delayed until autumn 2009. The overall OPTIPOL objective is to develop knowledge and tools to improve the decision on environmental friendly power-line routing. To achieve this goal the work is subdivided into 9 focal areas; Develop a 'least-cost path' GIS-based application for an environmental friendly routing of power lines based on ecological, financial and technological criteria; Assess habitat use of power-line Rights-of-Way (ROW) by different wildlife species, consider actions of improving power-line ROW as wildlife habitats, and evaluate possible positive and negative effects on wildlife of power-line ROWs. More specific we will examine how power-line ROW may offer suitable feeding grounds for moose and see if the species habitat selection is influenced by power line ROW; Assess population impact of bird mortality due to power-line collisions, relative to other human related mortality factors (primarily hunting) in gallinaceous birds (with capercaillie and black grouse as model species); Identify ecological high-risk factors for bird collisions, i.e. site-specific factors connected to topographic characteristics, including vegetation structure, season, weather and light conditions; Establish a national infrastructure for management of dead bird data (including birds re-corded as collision and electrocution victims) by developing an online web application enabling the general public to contribute with data on recorded dead birds via Internet; Review available literature to assess 1) the possibilities for increased collision hazard to birds by making power-line structures less visible for humans given the present knowledge on bird vision, and 2) technical properties and constraints of camouflaging techniques on conductors and earth wires; Review available

LDPC Code Design for Nonuniform Power-Line Channels

Directory of Open Access Journals (Sweden)

Sanaei Ali

2007-01-01

Full Text Available We investigate low-density parity-check code design for discrete multitone channels over power lines. Discrete multitone channels are well modeled as nonuniform channels, that is, different bits experience various channel parameters. We propose a coding system for discrete multitone channels that allows for using a single code over a nonuniform channel. The number of code parameters for the proposed system is much greater than the number of code parameters in conventional channel. Therefore, search-based optimization methods are impractical. We first formulate the problem of optimizing the rate of an irregular low-density parity-check code, with guaranteed convergence over a general nonuniform channel, as an iterative linear programming which is significantly more efficient than search-based methods. Then we use this technique for a typical power-line channel. The methodology of this paper is directly applicable to all decoding algorithms for which a density evolution analysis is possible.

On-line Dynamic Security Assessment in Power Systems

DEFF Research Database (Denmark)

Weckesser, Johannes Tilman Gabriel

and solar radiation. Moreover, ongoing research suggests that demand response will be introduced to maintain power balance between generation and consumption at all times. Due to these changes the operating point of the power system will be less predictable and today’s stability and security assessment...... for early prediction of critical voltage sags is described. The method’s performance is compared to other prediction approaches. The results show that the proposed method succeeds in early, accurately and consistently predicting critically low voltage sags. An efficient on-line DSA not only identifies...

Beam Optics for Typical Part of ISOL Beam Lines

International Nuclear Information System (INIS)

Jang, Ji Ho; Kwon, Hyeok Jung; Kim, Han Sung; Cho, Yong Sub

2013-01-01

KOMAC (Korea Multi-purpose Accelerator Complex) is doing a project, the detailed design of the ISOL beam lines for the heavy ion accelerator project of IBS (Institute of Basic Science) from August 2013 to February 2014. The heavy ion beams are transported by using the electrostatic quadrupoles and electrostatic benders between the equipment. The work-scope of the project is the beam optics design of the beam lines and the detailed design of the beam optics components, the electrostatic quadrupoles and the electrostatic bender. This work summarized the initial result of beam optics design of the beam line. We performed the beam optics simulation in two regions of ISOL beam lines and found that beam envelope is less than 2 cm. We will check that the poletip file values are reasonable or not in near future, and we also applied this method to the other parts of the ISOL beam line and optimize them. The result will be used the detailed design of the electrostatic quadrupoles and benders

Wired: impacts of increasing power line use by a growing bird population

Science.gov (United States)

Moreira, Francisco; Encarnação, Vitor; Rosa, Gonçalo; Gilbert, Nathalie; Infante, Samuel; Costa, Julieta; D'Amico, Marcello; Martins, Ricardo C.; Catry, Inês

2017-02-01

Power lines are increasingly widespread across many regions of the planet. Although these linear infrastructures are known for their negative impacts on bird populations, through collision and electrocution, some species take advantage of electricity pylons for nesting. In this case, estimation of the net impact of these infrastructures at the population level requires an assessment of trade-offs between positive and negative impacts. We compiled historical information (1958-2014) of the Portuguese white stork Ciconia ciconia population to analyze long-term changes in numbers, distribution range and use of nesting structures. White stork population size increased 660% up to 12000 breeding pairs between 1984 and 2014. In the same period, the proportion of nests on electricity pylons increased from 1% to 25%, likely facilitated by the 60% increase in the length of the very high tension power line grid (holding the majority of the nests) in the stork’s distribution range. No differences in breeding success were registered for storks nesting on electricity pylons versus other structures, but a high risk of mortality by collision and electrocution with power lines was estimated. We discuss the implications of this behavioral change, and of the management responses by power line companies, both for stork populations and for managers.

A Simplified Control Method for Tie-Line Power of DC Micro-Grid

Directory of Open Access Journals (Sweden)

Yanbo Che

2018-04-01

Full Text Available Compared with the AC micro-grid, the DC micro-grid has low energy loss and no issues of frequency stability, which makes it more accessible for distributed energy. Thus, the DC micro-grid has good potential for development. A variety of renewable energy is included in the DC micro-grid, which is easily affected by the environment, causing fluctuation of the DC voltage. For grid-connected DC micro-grid with droop control strategy, the tie-line power is affected by fluctuations in the DC voltage, which sets higher requirements for coordinated control of the DC micro-grid. This paper presents a simplified control method to maintain a constant tie-line power that is suitable for the DC micro-grid with the droop control strategy. By coordinating the designs of the droop control characteristics of generators, energy storage units and grid-connected inverter, a dead band is introduced to the droop control to improve the system performance. The tie-line power in the steady state is constant. When a large disturbance occurs, the AC power grid can provide power support to the micro-grid in time. The simulation example verifies the effectiveness of the proposed control strategy.

A field experiment on power line stabilization by SMES system

International Nuclear Information System (INIS)

Irie, F.; Takeo, M.; Sato, S.; Katahira, O.; Fukui, F.; Takamatsu, M.

1992-01-01

In this paper field experiments on stabilization of a hydro power plant by a SMES system are reported, where a generator having a rating of 60 kW at 3.3kV is connected to a 6.6kV power distribution line. The SMES system is composed of two 30kVA GTO convertors and a superconducting magnet system with an energy of 30kJ at 100A. Experiments of stabilization for the generator fluctuation caused by a sudden insertion of inductors in the line are successfully performed for some control modes. The value of the SMES system to compensate for a short period voltage dip is also confirmed

Discretionary power on the front-line

DEFF Research Database (Denmark)

Sanden, Guro Refsum; Lønsmann, Dorte

2018-01-01

This article investigates the communication practices used by front-line employees to cross language boundaries in the context of English language policies implemented by the management of three multinational corporations headquartered in Scandinavia. Based on an analysis of interview and document...... data, our findings show that employees face a number of different language boundaries in their everyday work, and that ad hoc and informal solutions in many cases are vital for successful cross-language communication. We introduce the concept of discretionary power to explain how and why front...

Discretionary Power on the Front Line

DEFF Research Database (Denmark)

Sanden, Guro Refsum; Lønsmann, Dorte

2018-01-01

This paper investigates the communication practices used by front-line employees to cross language boundaries in the context of English language policies implemented by the management of three multinational corporations (MNCs) headquartered in Scandinavia. Based on an analysis of interview...... and document data, our findings show that employees face a number of different language boundaries in their everyday work, and that ad hoc and informal solutions in many cases are vital for successful cross-language communication. We introduce the concept of 'discretionary power' to explain how and why front...

Construction of a 500 kV aerial power line in East Java

Energy Technology Data Exchange (ETDEWEB)

Kaeufl, O; Paschen, R; Kummermehr, R

1987-10-12

The authors report on the technical preparations and the construction of a 500 kv, four-bundle power line with a pylon tonnage of approximately 10,000 t of steel and a route length of 251 km in Indonesia. Due to the difficult terrain conditions, the sensitive infrastructure and the extremely short construction period, this project was a special technological challenge. Initially, the authors explain the technical planning of Brown Boveri with emphasis on foundations and assembly. As part of this tailor-made concept new technological solutions were used. They were instrumental in the successful completion of the project in only 19 months by the end of 1986 to the complete satisfaction of the customer. The authors also comment on the pracitcal experiences gained during the construction.

30 CFR 56.12071 - Movement or operation of equipment near high-voltage power lines.

Science.gov (United States)

2010-07-01

...-voltage power lines. 56.12071 Section 56.12071 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... NONMETAL MINES Electricity § 56.12071 Movement or operation of equipment near high-voltage power lines. When equipment must be moved or operated near energized high-voltage powerlines (other than trolley...

Power lines, roads, and avian nest survival: effects on predator identity and predation intensity.

Science.gov (United States)

DeGregorio, Brett A; Weatherhead, Patrick J; Sperry, Jinelle H

2014-05-01

1 Anthropogenic alteration of landscapes can affect avian nest success by influencing the abundance, distribution, and behavior of predators. Understanding avian nest predation risk necessitates understanding how landscapes affect predator distribution and behavior. 2 From a sample of 463 nests of 17 songbird species, we evaluated how landscape features (distance to forest edge, unpaved roads, and power lines) influenced daily nest survival. We also used video cameras to identify nest predators at 137 nest predation events and evaluated how landscape features influenced predator identity. Finally, we determined the abundance and distribution of several of the principal predators using surveys and radiotelemetry. 3 Distance to power lines was the best predictor of predator identity: predation by brown-headed cowbirds (Molothrus ater), corvids (Corvus sp. and Cyanocitta cristata), racers (Coluber constrictor), and coachwhips (Masticophis flagellum) increased with proximity to power lines, whereas predation by rat snakes (Elaphe obsoleta) and raptors decreased. In some cases, predator density may reliably indicate nest predation risk because racers, corvids, and cowbirds frequently used power line right-of-ways. 4 Of five bird species with enough nests to analyze individually, daily nest survival of only indigo buntings (Passerina cyanea) decreased with proximity to power lines, despite predation by most predators at our site being positively associated with power lines. For all nesting species combined, distance to unpaved road was the model that most influenced daily nest survival. This pattern is likely a consequence of rat snakes, the locally dominant nest predator (28% of predation events), rarely using power lines and associated areas. Instead, rat snakes were frequently associated with road edges, indicating that not all edges are functionally similar. 5 Our results suggest that interactions between predators and landscape features are likely to be specific to

ENVIRONMENTAL POLLUTION BY MAGNETIC FIELD AROUND POWER LINES

Directory of Open Access Journals (Sweden)

Vesna Ranković

2009-09-01

Full Text Available According to the contemporary epidemiological researches, there are some indications that extremely low frequency electromagnetic fields harm human health which has been proved through numerous scientific studies published in recent years. Today, most countries use the ICNIRP guidelines and Council Recommendation as the scientific basis for their recommended levels of exposure. Magnetic fields from high voltage transmission power lines have been discussed in this paper. The field profiles and their contribution to environmental pollution are studied. The obtained results are found to be useful for discussing the comparison of the field densities on the human body at the ground level under or near the lines.

Resilience of electricity grids against transmission line overloads under wind power injection at different nodes.

Science.gov (United States)

Schiel, Christoph; Lind, Pedro G; Maass, Philipp

2017-09-14

A steadily increasing fraction of renewable energy sources for electricity production requires a better understanding of how stochastic power generation affects the stability of electricity grids. Here, we assess the resilience of an IEEE test grid against single transmission line overloads under wind power injection based on the dc power flow equations and a quasi-static grid response to wind fluctuations. Thereby we focus on the mutual influence of wind power generation at different nodes. We find that overload probabilities vary strongly between different pairs of nodes and become highly affected by spatial correlations of wind fluctuations. An unexpected behaviour is uncovered: for a large number of node pairs, increasing wind power injection at one node can increase the power threshold at the other node with respect to line overloads in the grid. We find that this seemingly paradoxical behaviour is related to the topological distance of the overloaded line from the shortest path connecting the wind nodes. In the considered test grid, it occurs for all node pairs, where the overloaded line belongs to the shortest path.

Long-pulse applications of pulse-forming lines for high-power linac application

International Nuclear Information System (INIS)

Hoeberling, R.F.; Tallerico, P.J.

1981-01-01

The ever present demands for high efficiency in the RF power stations for particle accelerators have caused increased interest in longer RF pulses (ten's of microseconds) for linacs such as the Pion Generator for Medical Irradiation (PIGMI) and Free Electron Laser (FEL). For either RF power station, a fundamental decision is whether to use a modulating anode/hard-tube driver or pulsed cathode/line-type pulser configuration. The choices in the extremes of low power for very long pulses or for very-high-power, short pulses are, respectively, a modulated anode/hard tube modulator and pulsed cathode/pulse forming line. However, the demarcation between these two extremes is not clearcut. The criteria (cost, flexibility performance, reliability, efficiency) that resulted in the RF station definition of these two specific systems will be described

A Multilayer Perceptron-Based Impulsive Noise Detector with Application to Power-Line-Based Sensor Networks

KAUST Repository

Chien, Ying-Ren; Chen, Jie-Wei; Xu, Sendren Sheng-Dong

2018-01-01

For power-line-based sensor networks, impulsive noise (IN) will dramatically degrade the data transmission rate in the power line. In this paper, we present a multilayer perceptron (MLP)-based approach to detect IN in orthogonal frequency

Optimization design of toroidal core for magnetic energy harvesting near power line by considering saturation effect

Science.gov (United States)

Park, Bumjin; Kim, Dongwook; Park, Jaehyoung; Kim, Kibeom; Koo, Jay; Park, HyunHo; Ahn, Seungyoung

2018-05-01

Recently, magnetic energy harvesting technologies have been studied actively for self-sustainable operation of applications around power line. However, magnetic energy harvesting around power lines has the problem of magnetic saturation, which can cause power performance degradation of the harvester. In this paper, optimal design of a toroidal core for magnetic energy harvesters has been proposed with consideration of magnetic saturation near power lines. Using Permeability-H curve and Ampere's circuital law, the optimum dimensional parameters needed to generate induced voltage were analyzed via calculation and simulation. To reflect a real environment, we consider the nonlinear characteristic of the magnetic core material and supply current through a 3-phase distribution panel used in the industry. The effectiveness of the proposed design methodology is verified by experiments in a power distribution panel and takes 60.9 V from power line current of 60 A at 60 Hz.

Acoustic power balance in lined ducts

Science.gov (United States)

Eversman, W.

1979-01-01

It is shown that the two common definitions of acoustic energy density and intensity in uniform unlined ducts carrying uniform flow are compatible to the extent that both energy densities can be used in an appropriate variational principle to derive the convected wave equation. When the duct walls are lined both energy densities must be modified to account for the wall energy density. This results in a new energy conservation equation which utilizes a modified definition of axial power and accounts for wall dissipation. Computations in specific cases demonstrate the validity of the modified acoustic energy relation.

Decentralized automatic generation control of interconnected power systems incorporating asynchronous tie-lines.

Science.gov (United States)

Ibraheem; Hasan, Naimul; Hussein, Arkan Ahmed

2014-01-01

This Paper presents the design of decentralized automatic generation controller for an interconnected power system using PID, Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). The designed controllers are tested on identical two-area interconnected power systems consisting of thermal power plants. The area interconnections between two areas are considered as (i) AC tie-line only (ii) Asynchronous tie-line. The dynamic response analysis is carried out for 1% load perturbation. The performance of the intelligent controllers based on GA and PSO has been compared with the conventional PID controller. The investigations of the system dynamic responses reveal that PSO has the better dynamic response result as compared with PID and GA controller for both type of area interconnection.

Development of Live-working Robot for Power Transmission Lines

Science.gov (United States)

Yan, Yu; Liu, Xiaqing; Ren, Chengxian; Li, Jinliang; Li, Hui

2017-07-01

Dream-I, the first reconfigurable live-working robot for power transmission lines successfully developed in China, has the functions of autonomous walking on lines and accurately positioning. This paper firstly described operation task and object of the robot; then designed a general platform, an insulator replacement end and a drainage plate bolt fastening end of the robot, presented a control system of the robot, and performed simulation analysis on operation plan of the robot; and finally completed electrical field withstand voltage tests in a high voltage hall as well as online test and trial on actual lines. Experimental results show that by replacing ends of manipulators, the robot can fulfill operation tasks of live replacement of suspension insulators and live drainage plate bolt fastening.

Characterization and analysis of weld lines on micro-injection moulded parts using atomic force microscopy (AFM)

DEFF Research Database (Denmark)

Tosello, Guido; Gava, Alberto; Hansen, Hans Nørgaard

2009-01-01

In recent years plastic moulding techniques, such as injection moulding, have been developed to fulfil the needs of micro-components fabrication. Micro-injection moulding (SLIM) is the process which enables the mass production of polymer micro-systems such as micro-mechanical parts, micro...... the two original flows will generate and a weld line is formed on the surface of the micro-moulded part. This phenomenon has to be avoided or at least reduced, since in the weld line area the mechanical properties are poorer than in the bulk part, creating strength problems on the final part. Although...... injection moulding parameters on the weld lines' dimensions is presented, using an atomic force microscope (AFM). Depth and width of weld lines were chosen as parameters to be optimized....

Optimization Design of an Inductive Energy Harvesting Device for Wireless Power Supply System Overhead High-Voltage Power Lines

Directory of Open Access Journals (Sweden)

Wei Wang

2016-03-01

Full Text Available Overhead high voltage power line (HVPL online monitoring equipment is playing an increasingly important role in smart grids, but the power supply is an obstacle to such systems’ stable and safe operation, so in this work a hybrid wireless power supply system, integrated with inductive energy harvesting and wireless power transmitting, is proposed. The energy harvesting device extracts energy from the HVPL and transfers that from the power line to monitoring equipment on transmission towers by transmitting and receiving coils, which are in a magnetically coupled resonant configuration. In this paper, the optimization design of online energy harvesting devices is analyzed emphatically by taking both HVPL insulation distance and wireless power supply efficiency into account. It is found that essential parameters contributing to more extracted energy include large core inner radius, core radial thickness, core height and small core gap within the threshold constraints. In addition, there is an optimal secondary coil turn that can maximize extracted energy when other parameters remain fixed. A simple and flexible control strategy is then introduced to limit power fluctuations caused by current variations. The optimization methods are finally verified experimentally.

Power lines and birds. A summary of general and grid-specific issues; Kraftledninger og fugl. Oppsummering av generelle og nettspesifikke prob-lemstillinger

Energy Technology Data Exchange (ETDEWEB)

Bevanger, Kjetil

2011-02-15

To achieve European-level policy goals on climate change challenges, as well securing the electricity supply within Norway, it will be necessary to increase power line construction efforts significantly, as well as to upgrade the existing grid. Statnett have estimated an approximately 40 billion NOK investment over the next 10 years will be required for the central grid. Although this is a huge investment, the length of the new transmission lines constructed will only comprise a small part of the Norwegian grid. Of approximately 193 000 km of overhead power lines in Norway the distribution grid (i.e. up to 24 kV) comprises 85%. In this report we discuss the ornithological challenges connected to the different elements of the Norwegian grid. All overhead wires pose a potential risk to flying birds; however, the risk increases with the number of lines and wire length per unit of land area. The central and regional grid, in general, represents no electrocution threat, as the distances between the phase conductors and/or the distance between a phase conductor and an earthed device is rather wide. Thus the electrocution problem is a distribution grid specific problem. Both the collision and the electrocution risk are highly species specific problems. Over the last years several research projects have collected data enabling an identification of the bird species and bird species groups facing a particular risk. However, there is still a lack of know-ledge in several respects, for example why the number of collisions is not evenly distributed along a power line section, but is frequently concentrated at a few spots. This type of knowledge is crucial to contribute to the selection of as environmentally friendly power line routing as possible when new power lines are constructed. This is also stressed in the new Energy Act of 2009. With respect to both upgrading, and to new power line constructions, underground cabling should be used to a much greater extent. This will

Induced voltages in metallic pipelines near power transmission lines

International Nuclear Information System (INIS)

Grcev, Leonid; Jankov, Voislav; Filiposki, Velimir

2002-01-01

With the continuous development of the electric power system and the pipeline networks used to convey oil or natural gas, cases of close proximity of high voltage structures and metallic pipelines become more and more frequent. Accordingly there is a growing concern about possible hazards resulting from voltages induced in the metallic pipelines by magnetic coupling with nearby power transmission lines. This paper presents a methodology for computation of the induced voltages in buried isolated metallic pipelines. A practical example of computation is also presented. (Author)

Strain change and creep behavior of STACIR/AW power line with heat exposure

Energy Technology Data Exchange (ETDEWEB)

Kim, B.G.; Park, S.D.; Kim, S.S.; Lee, H.W. [Overhead Conductor Research Lab., Korea Electrotechnology Research Inst., Changwon (Korea)

2005-07-01

As a way to expand electric capacity in power line with hovering of electric power demand, STACIR/AW (super thermal-resistant Al alloy conductors Al-clad Invar-reinforced) overhead conductor which cans double ampacity has been developed. The STACIR/AW power line is mechanically composite stranded wire composed of INVAR/AW stranded wire as core for sag control and heat-resistant aluminum alloy for delivering doubled electric current. Recently, in order to ensure stable line operation and to predict its span of life, the changes of thermal properties for STACIR/AW have been investigated. In the present work, the changes of strain with temperature and the creep behavior as important factors in sag control will be presented. The transition temperature of STACIR/AW 410 sqmm was estimated approximately 130 C and the creep rates were decreased with temperatures. (orig.)

Virtual sensors for on-line wheel wear and part roughness measurement in the grinding process.

Science.gov (United States)

Arriandiaga, Ander; Portillo, Eva; Sánchez, Jose A; Cabanes, Itziar; Pombo, Iñigo

2014-05-19

Grinding is an advanced machining process for the manufacturing of valuable complex and accurate parts for high added value sectors such as aerospace, wind generation, etc. Due to the extremely severe conditions inside grinding machines, critical process variables such as part surface finish or grinding wheel wear cannot be easily and cheaply measured on-line. In this paper a virtual sensor for on-line monitoring of those variables is presented. The sensor is based on the modelling ability of Artificial Neural Networks (ANNs) for stochastic and non-linear processes such as grinding; the selected architecture is the Layer-Recurrent neural network. The sensor makes use of the relation between the variables to be measured and power consumption in the wheel spindle, which can be easily measured. A sensor calibration methodology is presented, and the levels of error that can be expected are discussed. Validation of the new sensor is carried out by comparing the sensor's results with actual measurements carried out in an industrial grinding machine. Results show excellent estimation performance for both wheel wear and surface roughness. In the case of wheel wear, the absolute error is within the range of microns (average value 32 μm). In the case of surface finish, the absolute error is well below Ra 1 μm (average value 0.32 μm). The present approach can be easily generalized to other grinding operations.

Artificial neural networks to estimate the EMF ELF on car travelling near power transmission line

Energy Technology Data Exchange (ETDEWEB)

Al-Sayegh, O.A.; Qabazard, A.M. [Kuwait Inst. for Scientific Research, Safat (Kuwait). advanced Systems Division of Environment and Urban

2007-07-01

An artificial neural network (ANN) was developed to determine the electromagnetic field (EMF) and extremely low frequency (ELF) intensity on a vehicle body at different distances from a high tension power line and at varying power loads. EMF radiated emissions from ELF source power transmission lines can produce interference in the electric components in vehicles traveling at variable speed near the power lines. The passengers in the vehicle may also experience EMF-related health problems. Although EMF has been recently categorized as a new form of pollution, the situation has been largely ignored by the industry. Typically, electromagnetic fields at different frequencies show the fastest growing environmental influences. All populations are now exposed to varying degrees of EMF and the levels will continue to increase as technology advances. The purpose of this work was to promote discussion and help find design solutions to manufacture a new device for measuring the EMF at variable speed. In this study, a set of near field measurements outside the vehicle were used to train ANN. Estimations of the EMF ELF for various distances from the high tension power line were presented. It was determined that the most important factors affecting the electric field model include exposure conditions; size, shape and position of the exposed body in the field; and, surface charge density. The EMF ELF was found to increase near sagging areas of the overhead power transmission line. The EMF ELF was found to be proportional to the total amps flowing through the line at the time of measurement. 14 refs., 3 figs.

Study of Power Converter Topologies with Energy Recovery and grid power flow control Part C: a review of alternative structures

CERN Document Server

Papastergiou, Konstantinos; Maestri, Sebastian; Retegui, Rogelio Garcia; Uicich, Gustavo; Benedetti, Mario; Carrica, Daniel

2017-01-01

In the framework of a Transfer line (TT2) Consolidation Programme, a number of studies on Energy cycling have been commissioned. Part of this work involves the study of different power electronic system topologies for magnet energy recovery. The key objective of the study is to find topologies and control strategies that result in the control of the peak power required from the power network as well as to recover the magnet energy into capacitor banks with controlled voltage fluctuation. In previous reports, the use of a boost front-end converter and two-quadrant (2Q) converter supplying DC link of a four-quadrant magnet supply were analyzed. From this analysis, different features and figures of merit were considered in order to compare the structures, which allowed to define some considerations that a proper topology should have. Consequently, these considerations were used to define some novel topologies. The previous topologies are briefly summarized, as a starting point to develop some novel struc...

Improvements of high-power diode laser line generators open up new application fields

Science.gov (United States)

Meinschien, J.; Bayer, A.; Bruns, P.; Aschke, L.; Lissotschenko, V. N.

2009-02-01

Beam shaping improvements of line generators based on high power diode lasers lead to new application fields as hardening, annealing or cutting of various materials. Of special interest is the laser treatment of silicon. An overview of the wide variety of applications is presented with special emphasis of the relevance of unique laser beam parameters like power density and beam uniformity. Complementary to vision application and plastic processing, these new application markets become more and more important and can now be addressed by high power diode laser line generators. Herewith, a family of high power diode laser line generators is presented that covers this wide spectrum of application fields with very different requirements, including new applications as cutting of silicon or glass, as well as the beam shaping concepts behind it. A laser that generates a 5m long and 4mm wide homogeneous laser line is shown with peak intensities of 0.2W/cm2 for inspection of railway catenaries as well as a laser that generates a homogeneous intensity distribution of 60mm x 2mm size with peak intensities of 225W/cm2 for plastic processing. For the annealing of silicon surfaces, a laser was designed that generates an extraordinary uniform intensity distribution with residual inhomogeneities (contrast ratio) of less than 3% over a line length of 11mm and peak intensities of up to 75kW/cm2. Ultimately, a laser line is shown with a peak intensity of 250kW/cm2 used for cutting applications. Results of various application tests performed with the above mentioned lasers are discussed, particularly the surface treatment of silicon and the cutting of glass.

Effects of Power Lines on Area Use and Behaviour of Semi-Domestic Reindeer in Enclosures

International Nuclear Information System (INIS)

Flydal, K.; Reimers, E.; Johansen, F.; Colman, J.E.; Korslund, L.; Colman, J.E.

2009-01-01

We conducted large-scale, replicated experiments to test the effects of two parallel power lines on area use, behaviour, and activity of semidomestic reindeer in enclosures. Yearling female reindeer were released into four 50 x 400 m enclosures; two treatment enclosures with power lines and two control enclosures. Reindeer from two herds, one from Kautokeino (domestic tame) and one from Vaga, (domestic wild) were tested separately and compared. Individual location within the enclosures was not affected by the power lines. Effects on restless behaviour were ambiguous, with slightly more restless behaviour in the treatment enclosures for the domestic tame reindeer, while the domestic wild reindeer maintained a stable level in the treatment enclosures, increasing with time in the control enclosures. Activity changes were slightly more common among animals within treatment enclosures for both herds, with no indication of habituation during the experiment. The domestic wild reindeer had more than three times the amount of restless behaviour than the domestic tame reindeer. Our study indicates that for reindeer in enclosures, the disturbance from a power line construction is negligible. This suggests that power lines are a minor disturbing factor compared to human handling when using fenced in areas like grazing gardens in reindeer husbandry.

Developing maximal neuromuscular power: Part 1--biological basis of maximal power production.

Science.gov (United States)

Cormie, Prue; McGuigan, Michael R; Newton, Robert U

2011-01-01

This series of reviews focuses on the most important neuromuscular function in many sport performances, the ability to generate maximal muscular power. Part 1 focuses on the factors that affect maximal power production, while part 2, which will follow in a forthcoming edition of Sports Medicine, explores the practical application of these findings by reviewing the scientific literature relevant to the development of training programmes that most effectively enhance maximal power production. The ability of the neuromuscular system to generate maximal power is affected by a range of interrelated factors. Maximal muscular power is defined and limited by the force-velocity relationship and affected by the length-tension relationship. The ability to generate maximal power is influenced by the type of muscle action involved and, in particular, the time available to develop force, storage and utilization of elastic energy, interactions of contractile and elastic elements, potentiation of contractile and elastic filaments as well as stretch reflexes. Furthermore, maximal power production is influenced by morphological factors including fibre type contribution to whole muscle area, muscle architectural features and tendon properties as well as neural factors including motor unit recruitment, firing frequency, synchronization and inter-muscular coordination. In addition, acute changes in the muscle environment (i.e. alterations resulting from fatigue, changes in hormone milieu and muscle temperature) impact the ability to generate maximal power. Resistance training has been shown to impact each of these neuromuscular factors in quite specific ways. Therefore, an understanding of the biological basis of maximal power production is essential for developing training programmes that effectively enhance maximal power production in the human.

On-line alkali monitoring - Part 1

International Nuclear Information System (INIS)

Andersson, Christer; Ljung, P.; Woxlin, H.

1997-02-01

As a consequence of the increased knowledge of the environmental impact of combustion based heat and power generation, the use of renewable biofuels will be increased. An obstacle associated to biofuel combustion compared to other fuels is the large release of alkali. Alkali compounds in flue gases are known to cause severe operational problems. Three of the major problems are; fouling of superheating tubes (causing reduced heat transfer and possibly corrosion), agglomeration of the bed material in fluidized beds, and poisoning of SCR catalysts. Yet another alkali related problem arises when, in order to increase the electric efficiency of combustion power plants, combined-cycle technology is used. Alkali vapour present in the fuel gas for the gas turbine is condensed to particles which increase corrosion and erosion of the turbine blades. The research on ash related operational problems has to be extended in order to ensure future use of biofuels in heat and power generation. In all successful research, adequate tools are necessary. To investigate ash related problems the key issue is to be able to perform continuous alkali measurements. This pilot study has investigated the need of continuous alkali measurements, which alkali species are harmful in the different applications and also available instrumentation capable of measuring the specific alkali species. The report gives a short summary presenting alkali related operational problems. In addition a schematic overview is given, showing the alkali species that possibly can exist in various parts of the power plant. 48 refs, 13 figs, 4 tabs

Location of Faults in Power Transmission Lines Using the ARIMA Method

Directory of Open Access Journals (Sweden)

Danilo Pinto Moreira de Souza

2017-10-01

Full Text Available One of the major problems in transmission lines is the occurrence of failures that affect the quality of the electric power supplied, as the exact localization of the fault must be known for correction. In order to streamline the work of maintenance teams and standardize services, this paper proposes a method of locating faults in power transmission lines by analyzing the voltage oscillographic signals extracted at the line monitoring terminals. The developed method relates time series models obtained specifically for each failure pattern. The parameters of the autoregressive integrated moving average (ARIMA model are estimated in order to adjust the voltage curves and calculate the distance from the initial fault localization to the terminals. Simulations of the failures are performed through the ATPDraw ® (5.5 software and the analyses were completed using the RStudio ® (1.0.143 software. The results obtained with respect to the failures, which did not involve earth return, were satisfactory when compared with widely used techniques in the literature, particularly when the fault distance became larger in relation to the beginning of the transmission line.

Power in health care organizations: contemplations from the first-line management perspective.

Science.gov (United States)

Isosaari, Ulla

2011-01-01

The aim of this paper is to examine health care organizations' power structures from the first-line management perspective. What liable power structures derive from the theoretical bases of bureaucratic, professional and result based organizations, and what power type do health care organizations represent, according to the empirical data? The paper seeks to perform an analysis using Mintzberg's power configurations of instrument, closed system, meritocracy and political arena. The empirical study was executed at the end of 2005 through a survey in ten Finnish hospital districts in both specialized and primary care. Respondents were all first-line managers in the area and a sample of staff members from internal disease, surgical and psychiatric units, as well as out-patient and primary care units. The number of respondents was 1,197 and the response percentage was 38. The data were analyzed statistically. As a result, it can be seen that a certain kind of organization structure supports the generation of a certain power type. A bureaucratic organization generates an instrument or closed system organization, a professional organization generates meritocracy and also political arena, and a result-based organization has a connection to political arena and meritocracy. First line managers regarded health care organizations as instruments when staff regarded them mainly as meritocracies having features of political arena. Managers felt their position to be limited by rules, whereas staff members regarded their position as having lots of space and influence potential. If the organizations seek innovative and active managers at the unit level, they should change the organizational structure and redistribute the work so that there could be more space for meaningful management. This research adds to the literature and gives helpful suggestions that will be of interest to those in the position of first-line management in health care.

Noise Sources, Effects and Countermeasures in Narrowband Power-Line Communications Networks: A Practical Approach

Directory of Open Access Journals (Sweden)

Gregorio López

2017-08-01

Full Text Available The integration of Distributed Generation, Electric Vehicles, and storage without compromising the quality of the power delivery requires the deployment of a communications overlay that allows monitoring and controlling low voltage networks in almost real time. Power Line Communications are gaining momentum for this purpose since they present a great trade-off between economic and technical features. However, the power lines also represent a harsh communications medium which presents different problems such as noise, which is indeed affected by Distributed Generation, Electric Vehicles, and storage. This paper provides a comprehensive overview of the types of noise that affects Narrowband Power Line Communications, including normative noises, noises coming from common electronic devices measured in actual operational power distribution networks, and noises coming from photovoltaic inverters and electric vehicle charging spots measured in a controlled environment. The paper also reviews several techniques to mitigate the effects of noise, paying special attention to passive filtering, as for being one of the most widely used solution to avoid this kind of problems in the field. In addition, the paper presents a set of tests carried out to evaluate the impact of some representative noises on Narrowband Power Line Communications network performance, as well as the effectiveness of different passive filter configurations to mitigate such an impact. In addition, the considered sources of noise can also bring value to further improve PLC communications in the new scenarios of the Smart Grid as an input to theoretical models or simulations.

Do power lines and protected areas present a catch-22 situation for Cape vultures (Gyps coprotheres)?

Science.gov (United States)

Phipps, W Louis; Wolter, Kerri; Michael, Michael D; MacTavish, Lynne M; Yarnell, Richard W

2013-01-01

Cape vulture Gyps coprotheres populations have declined across their range due to multiple anthropogenic threats. Their susceptibility to fatal collisions with the expanding power line network and the prevalence of carcasses contaminated with illegal poisons and other threats outside protected areas are thought to be the primary drivers of declines in southern Africa. We used GPS-GSM units to track the movements and delineate the home ranges of five adult (mean ±SD minimum convex polygon area = 121,655±90,845 km(2)) and four immature (mean ±SD minimum convex polygon area = 492,300±259,427 km(2)) Cape vultures to investigate the influence of power lines and their use of protected areas. The vultures travelled more than 1,000 km from the capture site and collectively entered five different countries in southern Africa. Their movement patterns and core foraging ranges were closely associated with the spatial distribution of transmission power lines and we present evidence that the construction of power lines has allowed the species to extend its range to areas previously devoid of suitable perches. The distribution of locations of known Cape vulture mortalities caused by interactions with power lines corresponded to the core ranges of the tracked vultures. Although some of the vultures regularly roosted at breeding colonies located inside protected areas the majority of foraging activity took place on unprotected farmland. Their ability to travel vast distances very quickly and the high proportion of time they spend in the vicinity of power lines and outside protected areas make Cape vultures especially vulnerable to negative interactions with the expanding power line network and the full range of threats across the region. Co-ordinated cross-border conservation strategies beyond the protected area network will therefore be necessary to ensure the future survival of threatened vultures in Africa.

Early environmental planning: A process for power line corridor selection

International Nuclear Information System (INIS)

Haagenstad, T.; Bare, C.M.

1998-01-01

Los Alamos National Laboratory (LANL) conducted an environmental planning study in the fall of 1997 to help determine the best alternative for upgrading the Laboratory's electrical power system. Alternatives considered included an on-site power generation facility and two corridors for a 10-mile-long 115-kV power line. This planning process was conducted prior to the formal National Environmental Policy Act (NEPA) review. The goals were to help select the best proposed action, to recommend modifications and mitigation measures for each alternative for a more environmentally sound project, and to avoid potential delays once the formal Department of Energy review process began. Significant constraints existed from a planning perspective, including operational issues such as existing outdoor high explosives testing areas, as well as environmental issues including threatened and endangered species habitats, multiple archeological sites, contaminated areas, and aesthetics. The study had to be completed within 45 days to meet project schedule needs. The process resulted in a number of important recommendations. While the construction and operation of the on-site power generation facility could have minimal environmental impacts, the need for a new air quality permit would create severe cost and schedule constraints for the project. From an environmental perspective, construction and operation of a power line within either corridor was concluded to be a viable alternative. However, impacts with either corridor would have to be reduced through specific recommended alignment modifications and mitigation measures

Relationship of the Functional Movement Screen In-Line Lunge to Power, Speed, and Balance Measures

OpenAIRE

Hartigan, Erin H.; Lawrence, Michael; Bisson, Brian M.; Torgerson, Erik; Knight, Ryan C.

2014-01-01

Background: The in-line lunge of the Functional Movement Screen (FMS) evaluates lateral stability, balance, and movement asymmetries. Athletes who score poorly on the in-line lunge should avoid activities requiring power or speed until scores are improved, yet relationships between the in-line lunge scores and other measures of balance, power, and speed are unknown. Hypothesis: (1) Lunge scores will correlate with center of pressure (COP), maximum jump height (MJH), and 36.6-meter sprint time...

THROUGH-THE EARTH (TTE) SYSTEM AND THE IN-MINE POWER LINE (IMPL) SYSTEM

International Nuclear Information System (INIS)

Zvi H. Meiksin

2001-01-01

Work has progressed on both subsystems: the through-the-earth (TTE) system and the In-Mine Power Line (IMPL) system. After the Lab prototype of the IMPL system was perfected to function satisfactorily, the thrust of the work focused on building a first production prototype that can be installed and tested inside a mine. To obtain multi-channel voice communication through the TTE system, effort has proceeded to compress voice messages and make the format compatible with the power-line interface protocol

Power electronics handbook components, circuits and applications

CERN Document Server

Mazda, F F

1993-01-01

Power Electronics Handbook: Components, Circuits, and Applications is a collection of materials about power components, circuit design, and applications. Presented in a practical form, theoretical information is given as formulae. The book is divided into three parts. Part 1 deals with the usual components found in power electronics such as semiconductor devices and power semiconductor control components, their electronic compatibility, and protection. Part 2 tackles parts and principles related to circuits such as switches; link frequency chargers; converters; and AC line control, and Part 3

Assessment of environmental impact of HVDC power lines in terms of corona currents

International Nuclear Information System (INIS)

Tikhodeev, N.N.

1997-01-01

Corona loss measurements were made on a HVDC power transmission line to evaluate current density. Ion currents were obtained from unipolar and bipolar 400 to 1000 kV DC test lines. A numerical solution was proposed for assessing the maximum current density of unipolar corona currents near the lines. A larger ground clearance of line conductors was proposed as being the most effective way of lowering the current density. 11 refs., 2 tabs., 4 figs

Flat tie-line power scheduling control of grid-connected hybrid microgrids

DEFF Research Database (Denmark)

Xiao, Zhao xia; Guerrero, Josep M.; Shuang, Jia

2018-01-01

In future active distribution networks (ADNs), microgrids (MGs) may have the possibility to control the power dispatched to the ADN by coordinating the output power of their multiple renewable generation units and energy storage units (ESUs). In this way, each MG may support the active distribution....... Also, a method to calculate the tie-line power flow to be exchanged between the MG and the ADN is explored, and a power ramp rate is given between different dispatch intervals. Finally, a simulation model of the hybrid MG is built and tested. Simulation results show that the proposed hierarchical...

An automated system for monitoring bird collisions with power lines and tower guys

Energy Technology Data Exchange (ETDEWEB)

Carlton, R.G. [Electric Power Research Inst., Palo Alto, CA (United States)

2005-07-01

An automated system for monitoring collisions between birds and power lines was presented. The bird strike indicator (BSI) was developed to gather bird collision information that is difficult to obtain through direct human observation as well as to aid in the calculation of inherent biases which must be considered when attempting to determine total mortality from data obtained in on-the-ground dead bird searches. The BSI can be placed directly on power lines, static wires, or tower guy cables with a standard hot stick power line clamp. The sensor consists of a state-of-the-art accelerometers, power supplies, signal processors, and data acquisition systems. The BSI also includes a communication system for transmitting data to a ground-based unit in which raw data can be stored. A complete BSI consists of 30 sensors with signal processing and data logging capabilities, and a base station. The sensors integrate several components, including wireless radio, data storage, and a microcontroller with an A/D converter. Full-scale field deployment has shown that the BSI is both robust and sensitive to vibrations in the guy wires, as the system has been tuned to eliminate vibrations induced by wind. 3 figs.

Transmission-line-circuit model of an 85-TW, 25-MA pulsed-power accelerator

OpenAIRE

B. T. Hutsel; P. A. Corcoran; M. E. Cuneo; M. R. Gomez; M. H. Hess; D. D. Hinshelwood; C. A. Jennings; G. R. Laity; D. C. Lamppa; R. D. McBride; J. K. Moore; A. Myers; D. V. Rose; S. A. Slutz; W. A. Stygar

2018-01-01

We have developed a physics-based transmission-line-circuit model of the Z pulsed-power accelerator. The 33-m-diameter Z machine generates a peak electrical power as high as 85 TW, and delivers as much as 25 MA to a physics load. The circuit model is used to design and analyze experiments conducted on Z. The model consists of 36 networks of transmission-line-circuit elements and resistors that represent each of Zs 36 modules. The model of each module includes a Marx generator, intermediate-en...

Distributed power-line outage detection based on wide area measurement system.

Science.gov (United States)

Zhao, Liang; Song, Wen-Zhan

2014-07-21

In modern power grids, the fast and reliable detection of power-line outages is an important functionality, which prevents cascading failures and facilitates an accurate state estimation to monitor the real-time conditions of the grids. However, most of the existing approaches for outage detection suffer from two drawbacks, namely: (i) high computational complexity; and (ii) relying on a centralized means of implementation. The high computational complexity limits the practical usage of outage detection only for the case of single-line or double-line outages. Meanwhile, the centralized means of implementation raises security and privacy issues. Considering these drawbacks, the present paper proposes a distributed framework, which carries out in-network information processing and only shares estimates on boundaries with the neighboring control areas. This novel framework relies on a convex-relaxed formulation of the line outage detection problem and leverages the alternating direction method of multipliers (ADMM) for its distributed solution. The proposed framework invokes a low computational complexity, requiring only linear and simple matrix-vector operations. We also extend this framework to incorporate the sparse property of the measurement matrix and employ the LSQRalgorithm to enable a warm start, which further accelerates the algorithm. Analysis and simulation tests validate the correctness and effectiveness of the proposed approaches.

On-line measurement of microwave power in ECR ion source

International Nuclear Information System (INIS)

Zhou Changgeng; Kang Wu; Hu Yonghong; Li Yan; Lou Benchao; Zu Xiulan; Xiong Riheng; Chen Junguang; Li Xiaoyun

2005-01-01

It is a new technology to apply an ECR ion source to the neutron generator. Because of the structure limitation, working state of the ECR ion source could not be judged by the color of gas discharging in discharge chamber. Therefore, it was hard to estimate if the ECR ion source was working properly in the neutron generator. The method to resolve the problem was described in this paper. The microwave power was measured on-line by a directional coupler and a small microwave power meter. The ion beam current could be educed from the measured incidence microwave power, and discharge state in discharge chamber could be determined. (authors)

High Voltage Overhead Power Line Routing under an Objective Observability Criterion

Directory of Open Access Journals (Sweden)

L. Alfredo Fernandez-Jimenez

2017-10-01

Full Text Available The construction of new high voltage overhead power lines (HVOPLs has become a controversial issue for electricity companies due to social opposition. Citizens are concerned about how these power lines may have an impact on their lives, basically caused by their effects on health and safety. Visual impact is one of the most easily perceived. Although there are several published works that deal with the assessment of the visual impact produced by HVOPLs, no methodology has been proposed to assess this impact from an objective perspective. This work presents an original methodology which helps to identify the optimal routes for a new HVOPL under an objective observability criterion, enabling the selection of those with the lowest visibility in a zone. The application of the proposed methodology achieves a set of routes that links new HVOPL origin and destination points creating a corridor which includes all possible routes with an observability of its towers under a threshold limit. This methodology is illustrated by a real-life use corresponding to the selection of the route with least observability for a new power line in La Rioja (Spain. The results obtained may help to achieve a consensus between key stakeholders since it is focused on the specific issues of the planned HVOPL and its observability from an objective perspective.

Does nuclear power have a part to play?

International Nuclear Information System (INIS)

Hampson, D.C.

1992-01-01

Uranium has three significant uses: the generation of electricity, the production of heat for industrial purposes and space heating, and the cogeneration of both heat and electric power. Electricity is the most widely used and rapidly growing form of secondary energy. All conservation scenarios, including that of the World Commission on Environmental and Development (The Brundtland Report), rely on its expanded use. This paper considers the current role of nuclear energy in meeting world electricity needs and the part played by Australian uranium. It reviews the work being done on the development of small and medium sized power reactors, the strengthening and expansion of the Australian electricity grind and the possibility that the combination of the two, together with environmental concerns, may provide the opportunity for nuclear power to play a part in our future energy mix. 5 refs., 1 tab., 5 figs

Improved Management of Part Safety Classification System for Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Park, Jin Young; Park, Youn Won; Park, Heung Gyu; Park, Hyo Chan [BEES Inc., Daejeon (Korea, Republic of)

2016-10-15

As, in recent years, many quality assurance (QA) related incidents, such as falsely-certified parts and forged documentation, etc., were reported in association with the supply of structures, systems, components and parts to nuclear power plants, a need for a better management of safety classification system was addressed so that it would be based more on the level of parts . Presently, the Korean nuclear power plants do not develop and apply relevant procedures for safety classifications, but rather the safety classes of parts are determined solely based on the experience of equipment designers. So proposed in this paper is a better management plan for safety equipment classification system with an aim to strengthen the quality management for parts. The plan was developed through the analysis of newly introduced technical criteria to be applied to parts of nuclear power plant.

Magnet power supply and beam line control for a secondary beam line K6

International Nuclear Information System (INIS)

Suzuki, Y.; Takasaki, M.; Minakawa, M.; Ishii, H.; Kato, Y.; Ieiri, M.; Tanaka, K.H.; Noumi, H.; Yamanoi, Y.

1992-01-01

K6 is a secondary separated-beam line with momentum range up to 2.0 GeV/c in the north experimental hall at the KEK 12 GeV Proton Synchrotron (KEK-PS). On the construction, newly developed magnet power supplies (MPSs), in each of them a microprocessor is embedded, are introduced. The features of the MPS are as follows: 1, The MPS is connected to an upper-level beam line controller (BLC) by GPIB highway for exchanging simple messages. 2, All the operations of the MPS are supervised by the microprocessor, which has its individual parameters and fault messages. It reduces the load of the upper-level controller. 3, The MPS has functions to inspect itself and to report the result. It saves much time and labor of maintenance. (author)

Possible mechanisms by which electric fields from power lines might affect airborne particles harmful to health

International Nuclear Information System (INIS)

Swanson, J.; Jeffers, D.

1999-01-01

Power lines produce alternating electric fields and modify static electric fields in their vicinity. These electric fields, if large enough, can alter the concentration or transport of airborne particles (including particles harmful to health), for example by causing deposition of charged particles, polarisation of neutral particles, or by production of ions. It has been suggested that this could lead to adverse health effects being associated with power lines. Theoretical considerations and experimental evidence relevant to eight separate postulated mechanisms involving power lines and airborne particles are examined. On theoretical grounds, none should lead to any adverse health effect, primarily because the effects produced are very small and are swamped by air currents or by gravity, and because people spend limited time in the relevant conditions. The experimental evidence also weighs against any adverse health effects. Further, even if significant health effects were produced, they would be different from those suggested by existing epidemiology concerning power lines. (author)

The various lines followed in the world

International Nuclear Information System (INIS)

Pierre, C.

1975-01-01

If the imaginable lines can be counted in hundreds, at least ten of them have effectively contributed to the production of energy and among them the LWR line (reactors cooled and moderated with ordinary water) represent 3/4 of the installed power and an even greater proportion of orders for nuclear power stations. The problems of fissile material supply will undoubtly make it imperative to have massive recourse to fast reactors, superregenerating reactors that produce more fissile material than they consume. Thanks to their special characteristics, high temperature reactors should also play a part. These three lines have, moreover, the advantage of being to a great extent complementary [fr

Proximity effects of high voltage electric power transmission lines on ...

African Journals Online (AJOL)

The proximity effects of high voltage electric power transmission lines on Leyland Cypress (xCupressocyparis leylandii (Dallim. and A.B. Jacks.) Dallim) and Japanese Privet (Ligustrum japonicum Thunb.) growth were examined in a private nursery located in Sakarya, Turkey. Five transect were randomly chosen in both ...

Quality electricity lines of external power systems electric traction DC

Directory of Open Access Journals (Sweden)

A.V. Petrov

2012-08-01

Full Text Available The results of studies that compare and analyze the numerical values of some key indicators quality electricity in the lines of the external power supply system the electric traction DC. As a supplement are additional and fundamental values of energy losses in them.

Troubleshooting of signal power supply system for Shanghai metro line 7

Science.gov (United States)

Lu, Kaixia; Xiao, Jie

2018-03-01

With the rapid development of Urban Rail Transit Signal Technology, the demand of signal power supply system for signal equipment is higher and higher. The signal intelligent power supply panel is the main component of the urban rail traffic signal power supply system. Whether the intelligent power supply panel working or not is directly related to traffic safety. The maintenance of intelligent signal power supply panel is particularly important. Line 7 of Shanghai Metro adopts PMZG Signal Intelligent Power Supply Panel, which is produced by Beijing Jinyujiaxin Polytron Technologies Inc. Maintenance of power supply system mainly includes routine maintenance and troubleshooting. This article will make clear the routine maintenance contents of PMZG Signal Intelligent Power Supply Panel, and put forward the common fault information and troubleshooting methods of PMZG Signal Intelligent Power Supply Panel. In accordance with the steps of fault handling, the faults can be eliminated in the shortest possible time, and PMZG Signal Intelligent Power Supply Panel can be quickly restored to normal working state.

The magnetic field near power lines in the Moscow region: the results of measurements and their analyze

Directory of Open Access Journals (Sweden)

Prokofyeva A.S.

2014-12-01

Full Text Available The aim: to analyze the real power frequency magnetic field (50 Hz values near power lines. The material. Long-term measurements of the power frequency magnetic field (50 Hz near power lines of 110 kV, 220 kVand 500 kVin the Moscow region. Methods. Measurements were made by tracks which were perpendicular to the wires. Length of tracks was up to 40 m. Sensor of measurer was located on 1.8 m under the ground. General quantity of measurement points were 1103. The results. Was obtained general characteristics of real values of strength of electric field and values of magnetic flux density depending to distance to the projection last wire near power lines. Conclusion. Analysis of the results has the values of the magnetic field of power lines correspond to the Russian rules in all cases. Using additional World Health Organization safety criteria for magnetic fields (the class of carcinogenic risks 2B requires the expansion of the health safety zone 2-3 times.

Mechanical Implementation and Simulation of MoboLab, A Mobile Robot for Inspection of Power Transmission Lines

Directory of Open Access Journals (Sweden)

Mahmud Saadat Foumani

2008-11-01

Full Text Available This paper describes the first phase in development of a mobile robot that can navigate aerial power transmission lines completely unattended by human operator. Its ultimate purpose is to automate inspection of power transmission lines and their equipments. The authors have developed a scaled functional model of such a mobile robot with a preliminary simple computer based on-off controller. MoboLab (Mobile Laboratory navigates a power transmission line between two strain towers. It can maneuver over obstructions created by line equipments such as insulators, warning spheres, dampers, and spacer dampers. It can also easily negotiate the towers by its three flexible arms. MoboLab has an internal main screw which enables the robot to move itself or its two front and rear arms independently through changing gripped points. When the front arm gets close to an obstacle, the arm detaches from the line and goes down, the robot moves forward, the arm passes the obstacle and grippes the line again. In a same way another arms pass the obstacle.

Integration of a hydraulic production plant in a weak power system on a long radial line

Energy Technology Data Exchange (ETDEWEB)

Lariviere, P. [Hydro-Quebec TransEnergie, 5655 de Marseille, Montreal, Quebec (Canada); Racine, M. [Hydro-Quebec TransEnergie, C.P. 10 000, Montreal, Quebec (Canada)

2009-03-15

Integrating power plants on long lines and weak power systems requires some care. To this effect, a study was conducted to determine if severe disturbances could result when a hydraulic production plant is integrated along a very long radial transmission line. Frequency responses were evaluated to identify possible resonant system operating conditions. Many events such as faults, transformer energyzing and line opening were investigated. All power plant synchronous machines were represented including exciter and governor regulators. Impact of dynamic modeling of the load was examined. The study demonstrates that the overall protective strategy implemented will limit worst overvoltage constraints imposed to equipment and load within an acceptable level. (author)

THE JET POWER AND EMISSION-LINE CORRELATIONS OF RADIO-LOUD OPTICALLY SELECTED QUASARS

International Nuclear Information System (INIS)

Punsly, Brian; Zhang Shaohua

2011-01-01

In this Letter, the properties of the extended radio emission form Sloan Digital Sky Survey Data Release 7 quasars with 0.4 20-30 kpc). The frequency of quasars with FR II level extended radio emission is ∼2.3% and >0.4% of quasars have FR I level extended radio emission. The lower limit simply reflects the flux density limit of the survey. The distribution of the long-term time-averaged jet powers of these quasars, Q-bar , has a broad peak ∼3 x 10 44 erg s -1 that turns over below 10 44 erg s -1 and sources above 10 45 erg s -1 are extremely rare. It is found that the correlation between the bolometric (total thermal) luminosity of the accretion flow, L bol , and Q-bar is not strong. The correlation of Q-bar with narrow line luminosity is stronger than the correlation with broad line luminosity and the continuum luminosity. It is therefore concluded that previous interpretations of correlations of Q-bar with narrow line strengths in radio galaxies as a direct correlation of jet power and accretion power have been overstated. It is explained why this interpretation mistakenly overlooks the sizeable fraction of sources with weak accretion luminosity and powerful jets discovered by Ogle et al.

Designing concept on lightning protection of overhead power distribution line

Energy Technology Data Exchange (ETDEWEB)

Yokoyama, Shigeru [Central Research Institute of Electric Power Industry, Kanagawa-ken (Japan)], E-mail: yokoyama@criepi.denken.or.jp

2007-07-01

The principle is shown for lightning protection of power distribution lines taking the effects of surge arresters, overhead ground wires and their combined use into consideration. Moreover an outline of a rational design method targeting direct lightning hits, induced over voltages and back flow currents from high structures. (author)

Considerations in applying on-line IC techniques to BWR's

International Nuclear Information System (INIS)

Kaleda, R.J.

1992-01-01

Ion-Chromatography (IC) has moved from its traditional role as a laboratory analytical tool to a real time, dynamic, on-line measurement device to follow ppb and sub-ppb concentrations of deleterious impurities in nuclear power plants. Electric Power Research Institute (EPRI), individual utilities, and industry all have played significant roles in effecting the transition. This paper highlights considerations and the evolution in current on-line Ion Chromatography systems. The first applications of on-line techniques were demonstrated by General Electric (GE) under EPRI sponsorship at Rancho Seco (1980), Calvert Cliffs, and McGuire nuclear units. The primary use was for diagnostic purposes. Today the on-line IC applications have been expanded to include process control and routine plant monitoring. Current on-line IC's are innovative in design, promote operational simplicity, are modular for simplified maintenance and repair, and use field-proven components which enhance reliability. Conductivity detection with electronic or chemical suppression and spectrometric detection techniques are intermixed in applications. Remote multi-point sample systems have addressed memory effects. Early applications measured ionic species in the part per billion range. Today reliable part per trillion measurements are common for on-line systems. Current systems are meeting the challenge of EPRI guideline requirements. Today's on-line IC's, with programmed sampling systems, monitor fluid streams throughout a power plant, supplying data that can be trended, stored and retrieved easily. The on-line IC has come of age. Many technical challenges were overcome to achieve today's IC

A Multilayer Perceptron-Based Impulsive Noise Detector with Application to Power-Line-Based Sensor Networks

KAUST Repository

Chien, Ying-Ren

2018-04-10

For power-line-based sensor networks, impulsive noise (IN) will dramatically degrade the data transmission rate in the power line. In this paper, we present a multilayer perceptron (MLP)-based approach to detect IN in orthogonal frequency-division multiplexing (OFDM)-based baseband power line communications (PLCs). Combining the MLP-based IN detection method with the outlier detection theory allows more accurate identification of the harmful residual IN. For OFDM-based PLC systems, the high peak-to-average power ratio (PAPR) of the received signal makes detection of harmful residual IN more challenging. The detection mechanism works in an iterative receiver that contains a pre-IN mitigation and a post-IN mitigation. The pre-IN mitigation is meant to null the stronger portion of IN, while the post-IN mitigation suppresses the residual portion of IN using an iterative process. Compared with previously reported IN detectors, the simulation results show that our MLP-based IN detector improves the resulting bit error rate (BER) performance.

Power-line Interference Removal from ECG in Case of Power-line Frequency Variations

Directory of Open Access Journals (Sweden)

Todor Stoyanov

2008-10-01

Full Text Available The original version of the most successful approach for power-line (PL interference removal from ECG, called subtraction procedure, is based on linear segment detection in the signal and hardware synchronised analogue-to-digital conversion to cope with the PL frequency variations. However, this is not feasible for battery supplied devices and some computer-aided ECG systems. Recent improvements of the procedure apply software measurement of the frequency variations that allow a re-sampling of the contaminated signal with the rated PL frequency followed by interference removal and back re-sampling for restoration of the original time intervals. This study deals with a more accurate software frequency measurement and introduces a notch filtration as alternative to the procedure when no linear segments are encountered for long time, e.g. in cases of ventricular fibrillation or tachycardia. The result obtained with large PL frequency variations demonstrate very small errors, usually in the range of ± 20 μV for the subtraction procedure and ± 60 μV for the notch filtration, the last values strongly depending on the frequency contents of the QRS complexes.

Onboard power line conditioning system for an electric or hybrid vehicle

Science.gov (United States)

Kajouke, Lateef A.; Perisic, Milun

2016-06-14

A power line quality conditioning system for a vehicle includes an onboard rechargeable direct current (DC) energy storage system and an onboard electrical system coupled to the energy storage system. The energy storage system provides DC energy to drive an electric traction motor of the vehicle. The electrical system operates in a charging mode such that alternating current (AC) energy from a power grid external to the vehicle is converted to DC energy to charge the DC energy storage system. The electrical system also operates in a vehicle-to-grid power conditioning mode such that DC energy from the DC energy storage system is converted to AC energy to condition an AC voltage of the power grid.

Inductive line energy storage generator

Energy Technology Data Exchange (ETDEWEB)

Choi, P [Ecole Polytechnique, Palaiseau (France). Laboratoire de Physique des Milieux Ionises

1997-12-31

The inductive energy storage (IES) generator has long been considered to be the most efficient system for energy usage in large pulsed power system at the MA level. A number of parameters govern the efficiency of energy transfer between the storage capacitors and the load, and the level of current deliverable to the load. For high power system, the energy storage capacitors are arranged as a Marx generator. The primary constraints are the inductances in the various parts of the circuit, in particular, the upstream inductance between the Marx and the POS, and the downstream inductance between the POS and the load. This paper deals with the effect of replacing part of the upstream inductance with a transmission line and introduces the new concept of an inductive line for energy storage (ILES). Extensive parametric scans were carried out on circuit simulations to investigate the effect of this upstream transmission line. A model was developed to explain the operation of the ILES design based on the data obtained. Comparison with an existing IES generator shows that the ILES design offers a significant improvement in the maximum current and hence energy delivered to an inductive load. (author). 5 figs., 1 ref.

''PSAD'' on-line monitoring and aid to diagnosis workstation: a monitoring tool for EDF power plants

International Nuclear Information System (INIS)

Morel, J.; Mazalerat, J.M.; Monnier, B.; Cordier, R.

1993-01-01

Like other electricity utilities, Electricite de France seeks to enhance the safety and availability of its nuclear power plants. To this end, for over ten years EDF has been installing on each plant unit two monitoring systems of its own design, one to monitor the primary cooling system, and the other, the turbogenerator set. Since the beginning of this project, widespread progress has been made in techniques of signal acquisition and processing, and in diagnosis using artificial intelligence methods. EDF has decided to call on these advanced techniques in developing its new-generation monitoring equipment, and to integrate them in its development of a workstation for on-line monitoring and diagnosis-support (PSAD: Poste de Surveillance et d'Aide au Diagnostic). PSAD will be a tool for on-line monitoring of the main components in nuclear power plants (initially the main coolant pumps and turbogenerator sets, and soon thereafter, monitoring of internal structures, detection of loose parts in the primary cooling system, etc.). PSAD will provide plant personnel with indispensable support in their diagnosis of the condition of plant equipment. It will integrate user-friendly, high-performance systems that also free the operator from many day-to-day tasks. PSAD will have a flexible architecture, for optimum distribution of the computing power where it is most needed, thereby improving the quality of the data. This paper presents the project objectives and describes work currently under way to implement EDF's diagnosis-support strategy for the years to come. (authors). 5 figs., 6 refs

Stabilization and control of tie-line power flow of microgrid including wind generation by distributed energy storage

Energy Technology Data Exchange (ETDEWEB)

Molina, M.G.; Mercado, P.E. [CONICET, Instituto de Energia Electrica, Universidad Nacional de San Juan, Av. Libertador San Martin Oeste 1109, J5400ARL San Juan (Argentina)

2010-06-15

High penetration of wind generation in electrical microgrids causes fluctuations of tie-line power flow and significantly affects the power system operation. This can lead to severe problems, such as system frequency oscillations, and/or violations of power lines capability. With proper control, a distribution static synchronous compensator (DSTATCOM) integrated with superconducting magnetic energy storage (SMES) is able to significantly enhance the dynamic security of the power system. This paper proposes the use of a SMES system in combination with a DSTATCOM as effective distributed energy storage (DES) for stabilization and control of the tie-line power flow of microgrids incorporating wind generation. A new detailed model of the integrated DSTATCOM-SMES device is derived and a novel three-level control scheme is designed. The dynamic performance of the proposed control schemes is fully validated using MATLAB/Simulink. (author)

Calculation of Voltages in Electric Power Transmission Lines During Historic Geomagnetic Storms: An Investigation Using Realistic Earth Impedances

Science.gov (United States)

Lucas, Greg M.; Love, Jeffrey J.; Kelbert, Anna

2018-02-01

Commonly, one-dimensional (1-D) Earth impedances have been used to calculate the voltages induced across electric power transmission lines during geomagnetic storms under the assumption that much of the three-dimensional structure of the Earth gets smoothed when integrating along power transmission lines. We calculate the voltage across power transmission lines in the mid-Atlantic region with both regional 1-D impedances and 64 empirical 3-D impedances obtained from a magnetotelluric survey. The use of 3-D impedances produces substantially more spatial variance in the calculated voltages, with the voltages being more than an order of magnitude different, both higher and lower, than the voltages calculated utilizing regional 1-D impedances. During the March 1989 geomagnetic storm 62 transmission lines exceed 100 V when utilizing empirical 3-D impedances, whereas 16 transmission lines exceed 100 V when utilizing regional 1-D impedances. This demonstrates the importance of using realistic impedances to understand and quantify the impact that a geomagnetic storm has on power grids.

MATHEMATICAL MODEL OF POWER CONSUMPTION FOR SOME OIL PIPE-LINE SECTIONS WITH POOR OPERATIONAL STABILITY

Directory of Open Access Journals (Sweden)

J. N. Kolesnik

2005-01-01

Full Text Available Mathematical model of power consumption for technologically completed and non-completed oil pipe-line sections with poor operational stability has been developed on the basis of daily indices concerning oil transportation regimes. The model permits to take into account tendencies in power consumption under various time prediction cycles and ranges of oil freight turnover, changes in the bulk and characteristics of the transported oil, configuration and design parameters of oil pipe-line.

Relationship of the functional movement screen in-line lunge to power, speed, and balance measures.

Science.gov (United States)

Hartigan, Erin H; Lawrence, Michael; Bisson, Brian M; Torgerson, Erik; Knight, Ryan C

2014-05-01

The in-line lunge of the Functional Movement Screen (FMS) evaluates lateral stability, balance, and movement asymmetries. Athletes who score poorly on the in-line lunge should avoid activities requiring power or speed until scores are improved, yet relationships between the in-line lunge scores and other measures of balance, power, and speed are unknown. (1) Lunge scores will correlate with center of pressure (COP), maximum jump height (MJH), and 36.6-meter sprint time and (2) there will be no differences between limbs on lunge scores, MJH, or COP. Descriptive laboratory study. Level 3. Thirty-seven healthy, active participants completed the first 3 tasks of the FMS (eg, deep squat, hurdle step, in-line lunge), unilateral drop jumps, and 36.6-meter sprints. A 3-dimensional motion analysis system captured MJH. Force platforms measured COP excursion. A laser timing system measured 36.6-m sprint time. Statistical analyses were used to determine whether a relationship existed between lunge scores and COP, MJH, and 36.6-m speed (Spearman rho tests) and whether differences existed between limbs in lunge scores (Wilcoxon signed-rank test), MJH, and COP (paired t tests). Lunge scores were not significantly correlated with COP, MJH, or 36.6-m sprint time. Lunge scores, COP excursion, and MJH were not statistically different between limbs. Performance on the FMS in-line lunge was not related to balance, power, or speed. Healthy participants were symmetrical in lunging measures and MJH. Scores on the FMS in-line lunge should not be attributed to power, speed, or balance performance without further examination. However, assessing limb symmetry appears to be clinically relevant.

Power lines Phoenix and the making of the modern southwest

CERN Document Server

Needham, Andrew

2014-01-01

In 1940, Phoenix was a small, agricultural city of sixty-five thousand, and the Navajo Reservation was an open landscape of scattered sheepherders. Forty years later, Phoenix had blossomed into a metropolis of 1.5 million people and the territory of the Navajo Nation was home to two of the largest strip mines in the world. Five coal-burning power plants surrounded the reservation, generating electricity for export to Phoenix, Los Angeles, and other cities. Exploring the postwar developments of these two very different landscapes, Power Lines tells the story of the far-reaching environmental a

Facts and feelings : Framing effects in responses to uncertainties about high-voltage power lines

NARCIS (Netherlands)

de Vries, G.; de Bruijn, J.A.

2017-01-01

To ensure power supply security, electricity transmission system operators (TSOs) have to upscale high-voltage overhead power lines. However, upscaling frequently meets opposition. Opposition can be caused by uncertainties about risks and benefits and might lead to costly delays (Linder, 1995;

Power charging and discharging characteristics of smes connected to artificial transmission line

International Nuclear Information System (INIS)

Nitta, T.; Okada, T.; Shirai, Y.

1985-01-01

To consider the characteristics of SMES and to investigate problems on the operations of SMES in power systems, we carried out some experiments on an experimental network. In the network, a small superconducting magnet is connected to a small synchronous generator through a double thyristorized converter and transformers. The generator is connected to the regional power system through artifitial transmission lines, AC power into or out of SMES and reactive power are controlled. Furthermore, a computer simulation program is made for the experimental system. The results of the simulation are compared with those of the experiments. For the experiments and the simulation, the harmonics current-flow, power-flow, characteristics of the generator and so on, are discussed

Laser line shape and spectral density of frequency noise

International Nuclear Information System (INIS)

Stephan, G.M.; Blin, S.; Besnard, P.; Tam, T.T.; Tetu, M.

2005-01-01

Published experimental results show that single-mode laser light is characterized in the microwave range by a frequency noise which essentially includes a white part and a 1/f (flicker) part. We theoretically show that the spectral density (the line shape) which is compatible with these results is a Voigt profile whose Lorentzian part or homogeneous component is linked to the white noise and the Gaussian part to the 1/f noise. We measure semiconductor laser line profiles and verify that they can be fit with Voigt functions. It is also verified that the width of the Lorentzian part varies like 1/P where P is the laser power while the width of the Gaussian part is more of a constant. Finally, we theoretically show from first principles that laser line shapes are also described by Voigt functions where the Lorentzian part is the laser Airy function and the Gaussian part originates from population noise

CONCEPTS OF IMPROVING CURRENT PROTECTION OF POWER-GRID LINES

Directory of Open Access Journals (Sweden)

F. A. Romaniuk

2015-01-01

Full Text Available The  6–35  kV  power-grid  current  protection  serves  to  protect  the  transmission  lines against phase-to-phase short-circuits. The major disadvantage of it lies in the relatively large time delays of the last stages especially in the main sections of the grid owing to the stepped relay characteristics as well as a large number of the steps. A full-fledged protection of the 6–35 kV lines against inter-phase short circuits can be provided by the two-stage current protection: the first stage being the current cutoff without any time delay and the second stage – the maximum current protection where the time delay is linear contingent on the distance between the protection placement and the fault-point location. The article introduces the rating formulae for the time delays of the second-stage and their exemplary graphic presentation. The authors offer a variant for solving the problem with computation of the second-stage time delays in those instances where several feeders diverge from the bus bars of the substation located in the end of the protected line.Improving current protections for the 6–35 kV transmission lines with one-end power supply against interphase short-circuits can be based on the collective application of the following principles: accounting for the type and location of the short-circuit which provides for the high-performance cutoff zone instantaneous expansion and its independence on the mode of failure and the grid operation mode. It also allows increase of the last stage sensitiveness towards asymmetrical short-circuits; detection of the short-circuit location only on the results of fault currents measurement which simplifies the protection implementation; realization of the last (second protection stage with linear-dependent time delay which ensures potentiality of its operation speed increase.

Asymmetric Bimodal Exponential Power Distribution on the Real Line

Directory of Open Access Journals (Sweden)

Mehmet Niyazi Çankaya

2018-01-01

Full Text Available The asymmetric bimodal exponential power (ABEP distribution is an extension of the generalized gamma distribution to the real line via adding two parameters that fit the shape of peakedness in bimodality on the real line. The special values of peakedness parameters of the distribution are a combination of half Laplace and half normal distributions on the real line. The distribution has two parameters fitting the height of bimodality, so capacity of bimodality is enhanced by using these parameters. Adding a skewness parameter is considered to model asymmetry in data. The location-scale form of this distribution is proposed. The Fisher information matrix of these parameters in ABEP is obtained explicitly. Properties of ABEP are examined. Real data examples are given to illustrate the modelling capacity of ABEP. The replicated artificial data from maximum likelihood estimates of parameters of ABEP and other distributions having an algorithm for artificial data generation procedure are provided to test the similarity with real data. A brief simulation study is presented.

LEVELS OF EXTREMELY LOW-FREQUENCY ELECTRIC AND MAGNETIC FIELDS FROM OVERHEAD POWER LINES IN THE OUTDOOR ENVIRONMENT OF RAMALLAH CITY-PALESTINE.

Science.gov (United States)

Abuasbi, Falastine; Lahham, Adnan; Abdel-Raziq, Issam Rashid

2018-05-01

In this study, levels of extremely low-frequency electric and magnetic fields originated from overhead power lines were investigated in the outdoor environment in Ramallah city, Palestine. Spot measurements were applied to record fields intensities over 6-min period. The Spectrum Analyzer NF-5035 was used to perform measurements at 1 m above ground level and directly underneath 40 randomly selected power lines distributed fairly within the city. Levels of electric fields varied depending on the line's category (power line, transformer or distributor), a minimum mean electric field of 3.9 V/m was found under a distributor line, and a maximum of 769.4 V/m under a high-voltage power line (66 kV). However, results of electric fields showed a log-normal distribution with the geometric mean and the geometric standard deviation of 35.9 and 2.8 V/m, respectively. Magnetic fields measured at power lines, on contrast, were not log-normally distributed; the minimum and maximum mean magnetic fields under power lines were 0.89 and 3.5 μT, respectively. As a result, none of the measured fields exceeded the ICNIRP's guidelines recommended for general public exposures to extremely low-frequency fields.

Power line policy in practice. A pilot study; Hoogspanningslijnenbeleid in de praktijk. Een pilotonderzoek

Energy Technology Data Exchange (ETDEWEB)

Kelfkens, G.; Pruppers, M.J.M.

2008-07-01

A Quick Scan performed by RIVM among twelve municipalities with an overhead power line revealed that half of these municipalities were not aware of the power line policy recommended by the Netherlands Ministry of Housing, Spatial Planning and the Environment (VROM). Those municipalities where power lines are an (openly) debated public issue are generally well-informed on the recommended policy. Due to public pressure, these latter municipalities often take more stringent measures than those advised by the VROM; these include implementing specific measures for existing neighbourhoods and/or postponing construction plans for new neighbourhoods that have already received council approval. None of the municipalities interviewed had an information service specifically aimed at providing their residents with information on power lines. Results from international epidemiological investigations point to the possibility that children living in the vicinity of overhead power lines may have an enhanced risk of developing childhood leukaemia. At the end of 2005 the VROM issued a policy advice for municipalities, provinces and grid companies. The aim of this policy advice is to prevent situations from developing where children can be subjected to long-term exposure to magnetic fields due to overhead power lines. In such new situations, the Ministry advises local governments to reserve a buffer zone near the power line that is to be kept empty of home residences, schools and day-care centres. As the policy advice focuses on the framing or changing of zoning plans - procedures which may take several years - it is currently impossible to evaluate if this policy advice issued in 2005 has been successful. The Quick Scan was performed by order of the Inspectorate of the Ministry of Housing, Spatial Planning and the Environment of the Northwest Region of the Netherlands. The aim of the Inspectorate was to evaluate the role of the policy advice at the municipal level and the degree to

Determination Of Maximum Power Of The RSG-Gas At Power Operation Mode Using One Line Cooling System

International Nuclear Information System (INIS)

Hastuti, Endiah Puji; Kuntoro, Iman; Darwis Isnaini, M.

2000-01-01

In the frame of minimizing the operation-cost, operation mode using one line cooling system is being evaluated. Maximum reactor power shall be determined to assure that the existing safety criteria are not violated. The analysis was done by means of a core thermal hydraulic code, COOLOD-N. The code solves core thermal hydraulic equation at steady state conditions. By varying the reactor power as the input, thermal hydraulic parameters such as fuel cladding and fuel meat temperatures as well as safety margin against flow instability were calculated. Imposing the safety criteria to the results, maximum permissible power for this operation was obtained as much as 17.1 MW. Nevertheless, for operation the maximum power is limited to 15MW

Impedance-Source Networks for Electric Power Conversion Part I

DEFF Research Database (Denmark)

Siwakoti, Yam P.; Peng, Fang Zheng; Blaabjerg, Frede

2015-01-01

power chain, which may improve the reliability and performance of the power system. The first part of this paper provides a comprehensive review of the various impedance-source-networks-based power converters and discusses the main topologies from an application point of view. This review paper...... is the first of its kind with the aim of providing a “one-stop” information source and a selection guide on impedance-source networks for power conversion for researchers, designers, and application engineers. A comprehensive review of various modeling, control, and modulation techniques for the impedance...

Improved anchorage of steel linings at WWER nuclear power plants

International Nuclear Information System (INIS)

Bouda, M.; Cepicky, J.

1987-01-01

Three variants were tested of anchoring the steel lining of special structures of nuclear power plants with WWER reactors, such as the containment, viz.: point anchorage with pins according to a Czechoslovak design, and two methods of linear anchorage according to a Soviet design and a design by the Institute for Industrial Construction of the GDR. Graphically shown are some results of the tests of the point anchorage with pins that showed the reliability of the method with respect to deformation and strain of the lining and of the anchoring elements at a lining temperature of up to 300 degC, which significantly exceeded the design-basis accident temperature of 150 degC. The advantages of the variant include a lower content of labour and an increased quality of welding jobs thanks to the application of the Nelson semi-automatic welding technique. (Z.M.). 10 figs., 7 refs

English as a Second Language for Automotive Component Parts Line Operators.

Science.gov (United States)

Lewandowski, Carol

This document is one of a series of student workbooks developed for workplace skill development courses or workshops by Mercer County Community College (New Jersey) and its partners. Designed to improve the English speaking and reading skills of non-English-speaking automotive component parts line operators, the course covers oral, written,…

Software for evaluating magnetic induction field generated by power lines: implementation of a new algorithm

International Nuclear Information System (INIS)

Comelli, M.; Benes, M.; Bampo, A.; Villalta, R.

2006-01-01

The Regional Environment Protection Agency of Friuli Venezia Giulia (A.R.P.A. F.V.G., Italy) has performed an analysis on existing software designed to calculate magnetic induction field generated by power lines. As far as the agency requirements are concerned the tested programs display some difficulties in the immediate processing of electrical and geometrical data supplied by plant owners, and in certain cases turn out to be inadequate in representing complex configurations of power lines. Furthermore, none of them is preset for cyclic calculus to determine the time evolution of induction in a certain exposure area. Finally, the output data are not immediately importable by ArcView, the G.I.S. used by A.R.P.A. F.V.G., and it is not always possible to implement the territory orography to determine the field at specified heights above the ground. P.h.i.d.e.l., an innovative software, tackles and works out al l the above mentioned problems. The power line wires interested in its implementation are represented by poly lines, and the field is analytically calculated, with no further approximation, not even when more power lines are concerned. Therefore, the obtained results, when compared with those of other programs, are the closest to experimental measurements. The output data can be employed both in G.I.S. and Excel environments, allowing the immediate overlaying of digital cartography and the determining of the 3 and 10 μT bands, in compliance with the Italian Decree of the President of the Council of Ministers of 8 July 2003. (authors)

On-line monitoring applications at nuclear power plants. A risk informed approach to calibration reduction

International Nuclear Information System (INIS)

Shankar, Ramesh; Hussey, Aaron; Davis, Eddie

2003-01-01

On-line monitoring of instrument channels provides increased information about the condition of monitored channels through accurate, more frequent evaluation of each cannel's performance over time. This type of performance monitoring is a methodology that offers an alternate approach to traditional time-directed calibration. EPRI's strategic role in on-line monitoring is to facilitate its implementation and cost-effective use in numerous applications at power plants. To this end, EPRI has sponsored an on-line monitoring implementation project at multiple nuclear plants specifically intended to install and use on-line monitoring technology. The selected on-line monitoring method is based on the Multivariate State Estimation Technique. The project has a planned three-year life; seven plants are participating in the project. The goal is to apply on-line monitoring to all types of power plant applications and document all aspects of the implementation process in a series of EPRI reports. These deliverables cover installation, modeling, optimization, and proven cost-benefit. This paper discusses the actual implementation of on-line monitoring to various nuclear plant instrument systems. Examples of detected instrument drift are provided. (author)

A methodology for on-line fatigue life monitoring of Indian nuclear power plant components

International Nuclear Information System (INIS)

Mukhopadhyay, N.K.; Dutta, B.K.; Kushawaha, H.S.

1992-01-01

Fatigue is one of the most important aging effects of nuclear power plant components. Information about accumulation of fatigue helps in assessing structural degradation of the components. This assists in-service inspection and maintenance and may also support future life extension program of a plant. In the present report a methodology is being proposed for monitoring on line fatigue life of nuclear power plant components using available plant instrumentations. Major factors affecting fatigue life of a nuclear power plant components are the fluctuations of temperature, pressure and flow rate. Green's function technique is used in on line fatigue monitoring as computation time is much less than finite element method. A code has been developed which computes temperature and stress Green's functions in 2-D and axisymmetric structure by finite element method due to unit change in various fluid parameters. A post processor has also been developed which computes the temperature and stress responses using corresponding Green's functions and actual fluctuation in fluid parameters. In this post processor, the multiple site problem is solved by superimposing single site Green's function technique. It is also shown that Green's function technique is best suited for on line fatigue life monitoring of nuclear power plant components. (author). 6 refs., 43 figs

Decommissioning of building part of nuclear power plant

International Nuclear Information System (INIS)

Sochor, R.

1988-01-01

The characteristics are discussed using literature data of building work during decommissioning or reconstruction of nuclear power plants. The scope of jobs associated with power plant decommissioning is mainly given by the size of contaminated parts, intensity of radioactivity, the volume of radioactive wastes and the possible building processes. Attention is devoted to the cost of such jobs and the effect of the plant design on cost reduction. (Z.M.). 6 refs

Flight route Designing and mission planning Of power line inspecting system Based On multi-sensor UAV

International Nuclear Information System (INIS)

Xiaowei, Xie; Zhengjun, Liu; Zhiquan, Zuo

2014-01-01

In order to obtain various information of power facilities such as spatial location, geometry, images data and video information in the infrared and ultraviolet band and so on, Unmanned Aerial Vehicle (UAV) power line inspecting system needs to integrate a variety of sensors for data collection. Low altitude and side-looking imaging are required for UAV flight to ensure sensors to acquire high-quality data and device security. In this paper, UAV power line inspecting system is deferent from existing ones that used in Surveying and Mapping. According to characteristics of UAV for example equipped multiple sensor, side-looking imaging, working at low altitude, complex terrain conditions and corridor type flight, this paper puts forward a UAV power line inspecting scheme which comprehensively considered of the UAV performance, sensor parameters and task requirements. The scheme is finally tested in a region of Guangdong province, and the preliminary results show that the scheme is feasible

Relationship of the Functional Movement Screen In-Line Lunge to Power, Speed, and Balance Measures

Science.gov (United States)

Hartigan, Erin H.; Lawrence, Michael; Bisson, Brian M.; Torgerson, Erik; Knight, Ryan C.

2014-01-01

Background: The in-line lunge of the Functional Movement Screen (FMS) evaluates lateral stability, balance, and movement asymmetries. Athletes who score poorly on the in-line lunge should avoid activities requiring power or speed until scores are improved, yet relationships between the in-line lunge scores and other measures of balance, power, and speed are unknown. Hypothesis: (1) Lunge scores will correlate with center of pressure (COP), maximum jump height (MJH), and 36.6-meter sprint time and (2) there will be no differences between limbs on lunge scores, MJH, or COP. Study Design: Descriptive laboratory study. Level of Evidence: Level 3. Methods: Thirty-seven healthy, active participants completed the first 3 tasks of the FMS (eg, deep squat, hurdle step, in-line lunge), unilateral drop jumps, and 36.6-meter sprints. A 3-dimensional motion analysis system captured MJH. Force platforms measured COP excursion. A laser timing system measured 36.6-m sprint time. Statistical analyses were used to determine whether a relationship existed between lunge scores and COP, MJH, and 36.6-m speed (Spearman rho tests) and whether differences existed between limbs in lunge scores (Wilcoxon signed-rank test), MJH, and COP (paired t tests). Results: Lunge scores were not significantly correlated with COP, MJH, or 36.6-m sprint time. Lunge scores, COP excursion, and MJH were not statistically different between limbs. Conclusion: Performance on the FMS in-line lunge was not related to balance, power, or speed. Healthy participants were symmetrical in lunging measures and MJH. Clinical Relevance: Scores on the FMS in-line lunge should not be attributed to power, speed, or balance performance without further examination. However, assessing limb symmetry appears to be clinically relevant. PMID:24790688

Adaptive on-line prediction of the available power of lithium-ion batteries

Science.gov (United States)

Waag, Wladislaw; Fleischer, Christian; Sauer, Dirk Uwe

2013-11-01

In this paper a new approach for prediction of the available power of a lithium-ion battery pack is presented. It is based on a nonlinear battery model that includes current dependency of the battery resistance. It results in an accurate power prediction not only at room temperature, but also at lower temperatures at which the current dependency is substantial. The used model parameters are fully adaptable on-line to the given state of the battery (state of charge, state of health, temperature). This on-line adaption in combination with an explicit consideration of differences between characteristics of individual cells in a battery pack ensures an accurate power prediction under all possible conditions. The proposed trade-off between the number of used cell parameters and the total accuracy as well as the optimized algorithm results in a real-time capability of the method, which is demonstrated on a low-cost 16 bit microcontroller. The verification tests performed on a software-in-the-loop test bench system with four 40 Ah lithium-ion cells show promising results.

Calculation of voltages in electric power transmission lines during historic geomagnetic storms: An investigation using realistic earth impedances

Science.gov (United States)

Lucas, Greg M.; Love, Jeffrey J.; Kelbert, Anna

2018-01-01

Commonly, one-dimensional (1-D) Earth impedances have been used to calculate the voltages induced across electric power transmission lines during geomagnetic storms under the assumption that much of the three-dimensional structure of the Earth gets smoothed when integrating along power transmission lines. We calculate the voltage across power transmission lines in the mid-Atlantic region with both regional 1-D impedances and 64 empirical 3-D impedances obtained from a magnetotelluric survey. The use of 3-D impedances produces substantially more spatial variance in the calculated voltages, with the voltages being more than an order of magnitude different, both higher and lower, than the voltages calculated utilizing regional 1-D impedances. During the March 1989 geomagnetic storm 62 transmission lines exceed 100 V when utilizing empirical 3-D impedances, whereas 16 transmission lines exceed 100 V when utilizing regional 1-D impedances. This demonstrates the importance of using realistic impedances to understand and quantify the impact that a geomagnetic storm has on power grids.

On-line Monitoring and Calibration Techniques in Nuclear Power Plants

International Nuclear Information System (INIS)

Hashemian, H.M.

2011-01-01

Years of research, testing and experience in the field of sensor diagnostics have yielded many technologies which offer financial as well as operational benefits to the nuclear industry. Among these technologies are On-Line Monitoring (OLM) and On-Line Calibration of critical process monitoring sensors such as resistance temperature detectors (RTD), thermocouples, and pressure transmitters to name a few. The remote access and verification of these sensors have been shown to limit the exposure of maintenance personnel to harsh environments while at the same time effectively and efficiently diagnosing the health and performance of these sensors. In addition to sensors, technologies exist in determining not only the health of instrumentation and control (I and C) cabling that carries the signals from these sensors, but also these same cable testing techniques can be used in the remote evaluation of many end devices used in safety related operations as well. Given these advances in sensor system monitoring techniques it would seem to follow that nuclear utilities from around the world would be applying these tried and true techniques to optimize up time and to provide additional confidence in the output of processing sensors. However, although several of the world's regulatory bodies have approved of the concept of these techniques, few utilities have undertaken to fully embrace on-line monitoring and on-line calibration of nuclear process sensors. In the United States efforts are now underway, with representatives of the U.S. nuclear industry and nuclear power plant vendors to obtain generic NRC licensing for the use of OLM in nuclear power plants. If approved, generic licensing will help pave the way toward greater implementation of OLM and its related calibration techniques. (author)

On Variable Reverse Power Flow-Part I: Active-Reactive Optimal Power Flow with Reactive Power of Wind Stations

Directory of Open Access Journals (Sweden)

Aouss Gabash

2016-02-01

Full Text Available It has recently been shown that using battery storage systems (BSSs to provide reactive power provision in a medium-voltage (MV active distribution network (ADN with embedded wind stations (WSs can lead to a huge amount of reverse power to an upstream transmission network (TN. However, unity power factors (PFs of WSs were assumed in those studies to analyze the potential of BSSs. Therefore, in this paper (Part-I, we aim to further explore the pure reactive power potential of WSs (i.e., without BSSs by investigating the issue of variable reverse power flow under different limits on PFs in an electricity market model. The main contributions of this work are summarized as follows: (1 Introducing the reactive power capability of WSs in the optimization model of the active-reactive optimal power flow (A-R-OPF and highlighting the benefits/impacts under different limits on PFs. (2 Investigating the impacts of different agreements for variable reverse power flow on the operation of an ADN under different demand scenarios. (3 Derivation of the function of reactive energy losses in the grid with an equivalent-π circuit and comparing its value with active energy losses. (4 Balancing the energy curtailment of wind generation, active-reactive energy losses in the grid and active-reactive energy import-export by a meter-based method. In Part-II, the potential of the developed model is studied through analyzing an electricity market model and a 41-bus network with different locations of WSs.

Enhanced power sharing in microgrids using the modified droop and virtual line impedance systems

Energy Technology Data Exchange (ETDEWEB)

Aghasafari, M.A.; Lopes, L.A.C.; Williamson, S. [Concordia Univ., Montreal, PQ (Canada). Power Electronics and Energy Research Group

2009-06-15

The microgrid is the local electricity network which connects several distributed energy systems. This paper proposed a control strategy which provided better power sharing than that of other control systems with low sensibility to the line unbalances, with fast and non-oscillatory responses. These distributed sources (which can include solar panels) were connected together using inverters in a low voltage microgrid. Power equations of the system were considered and presented from the droop strategy point of view and the importance of including virtual impedances in the control system was considered. The performance of the system was verified by means of simulations. Several illustrations and graphs were presented, including a simplified power stage of the system; power sharing variations by change in the first source voltage phase; power sharing variations as the first source voltage magnitude changes; power sharing variations by change in the system steady state frequency; and apparent power changes by change in the system steady state frequency. The control system and its levels was also illustrated including its four levels, namely an inverter current control loop; inverter voltage control loop; virtual resistance loop; and droop control loop. It was concluded that the control scheme for isolated microgrids yielded good speed, power sharing, and efficiency with small transient oscillations. The system could make good power sharing insensitive to the line unbalance. 8 refs., 1 tab., 11 figs.

Training of nuclear power facility personnel. Part 1

International Nuclear Information System (INIS)

1989-06-01

The proceedings of the conference entitled ''Training of Nuclear Power Facility Personnel'' and held in Tale, Czechoslovakia, on 24 - 27 April 1989, contain full texts of 58 contributions, 57 of which fall in the INIS subject scope. The aim of the conference was to summarize experience gained during the training and education of Czechoslovak nuclear power plants operating personnel, to put forth new suggestions for increasing the safety and reliability of nuclear power plants, and to establish the needs and new trends in the training and education of nuclear power plants personnel. The topics treated at the conference can be divided into three basic groups as follows: 1. professional qualification of nuclear power plant staff members; 2. development of technical means for the nuclear power plants personnel training; and 3. training of maintenance personnel, the system and organization of this training and education. The proceedings are published in two volumes. Part 1 contains the texts of 25 papers falling in the INIS subject scope. (Z.M.)

Review of fire behavior during passage of Sandy Lake Fire 13 (NWT) across a Northwest Territories Power Corporation transmission line

Energy Technology Data Exchange (ETDEWEB)

Schroeder, D.; Thomasson, J.

2009-03-15

The Sandy Lake Fire 13 of July 2008 was an intense forest fire that burned up to and across a power line right-of-way in the Northwest Territories, approximately 160 km northwest of Fort Smith. The terrain in the area is flat and vegetation is characterized by boreal pine and black spruce uplands with black spruce and tamarack in lower areas and adjacent to wetlands. This report documented post fire conditions at locations where the fire crossed the power line. The towers on this line were made from an aluminum alloy and may not have had the same resistance to heat damage as steel towers, more commonly used on major transmission lines. The transmission line was de-energized during the fire. Therefore, the effects of fire on power transmission were not documented. Although the intense wildfire crossed sections of the power line, it did not result in observable damage to the towers or lines. Fire intensity was likely greater than 40,000 kw/m along some sections of the right-of-way. Although the management of the right-of-way may have reduced heat exposure to the transmission towers, it did not stop the fire. Pine mixed with an aspen component greater than 50 per cent had a mitigating effect on fire behaviour. The fire did not result in any immediate damage to the power line infrastructure. It was concluded that the use of power lines for fire operations should consider right-of-way width in order to assess equipment maneuverability, especially around tower guy wires. 5 refs., 1 tab., 12 figs.

Simulation Analysis of Transmission-Line Impedance Transformers for Petawatt-Class Pulsed Power Accelerators

International Nuclear Information System (INIS)

Hu Yixiang; Qiu Aici; Sun Fengju; Huang Tao; Cong Peitian; Wang Liangping; Zeng Jiangtao; Li Yan; Zhang Xinjun; Lei Tianshi

2011-01-01

Based on the transmission line code TLCODE, a 1D circuit model for a transmission-line impedance transformer was developed and the simulation results were compared with those in the literature. The model was used to quantify the efficiencies of voltage-transport, energy-transport and power-transport for a transmission-line impedance transformer as functions of ψ (the ratio of the output impedance to the input impedance of the transformer) and Γ (the ratio of the pulse width to the one-way transit time of the transformer) under a large scale of m (the coefficient of the generalized exponential impedance profile). Simulation results suggest that with the increase in Γ, from 0 to ∞, the power transport efficiency first increases and then decreases. The maximum power transport efficiency can reach 90% or even higher for an exponential impedance profile (m = 1). With a consideration of dissipative loss in the dielectric and electrodes of the transformer, two representative designs of the water-insulated transformer are investigated for the next generation of petawatt-class z-pinch drivers. It is found that the dissipative losses in the electrodes are negligibly small, below 0.1%, but the dissipative loss in the water dielectric is about 1% to 4%. (fusion engineering)

Self-tuning wireless power transmission scheme based on on-line scattering parameters measurement and two-side power matching.

Science.gov (United States)

Luo, Yanting; Yang, Yongmin; Chen, Zhongsheng

2014-04-10

Sub-resonances often happen in wireless power transmission (WPT) systems using coupled magnetic resonances (CMR) due to environmental changes, coil movements or component degradations, which is a serious challenge for high efficiency power transmission. Thus self-tuning is very significant to keep WPT systems following strongly magnetic resonant conditions in practice. Traditional coupled-mode ways is difficult to solve this problem. In this paper a two-port power wave model is presented, where power matching and the overall systemic power transmission efficiency are firstly defined by scattering (S) parameters. Then we propose a novel self-tuning scheme based on on-line S parameters measurements and two-side power matching. Experimental results testify the feasibility of the proposed method. These findings suggest that the proposed method is much potential to develop strongly self-adaptive WPT systems with CMR.

Adaptive Capabilities of the Eastern Imperial Eagle in Power Lines Exploration for Nesting Purposes in the Republic of Tatarstan, Russia

Directory of Open Access Journals (Sweden)

Rinur H. Bekmansurov

2016-02-01

Full Text Available This report presents information on the eastern imperial eagle nesting on electricity pylons in the Republic of Tatarstan (area of 67836.2 km2 on the eastern part of East-European (Russian Plain, where the habitat of this species, marked in GIS (ArcView 3.2a, is 49 thousand km2. During the research in 2011–2015 5 nests were found on steel electricity pylons, which sustains 3.25% from the whole amount of nesting areas (n=154. Rather local disposition of all found cases of nests on electricity pylons in Eastern Zakamye (High Zavolzhye limited by one landscape subzone – typical and southern forest-steppe, and in only two landscape regions with adjacent borders – indicates some general conditions which caused the adaptation.  Distance between nests on power lines in the Republic of Tatarstan ranged from 21.5 to 49.9 km, averaging 29.5±13.64 km (n=5. As this territory lacks interspecific competition, the main reason of nesting on electricity pylons is probably the reduction of distance to forage resources in conditions of intraspecific competition in the densest nesting group. Adaptive capabilities of the Eastern Imperial Eagle are connected with their ability to occupy nests of other birds, high tolerance to human influence, and with the high density of the power lines and low density of long-boled forests. It’s reported that the imperial eagles’ adaptation to living in environment with dense power line network continues, which expresses in increase of the nesting on electricity pylons.

Fast Burst Synchronization for Power Line Communication Systems

Directory of Open Access Journals (Sweden)

Lampe Lutz

2007-01-01

Full Text Available Fast burst synchronization is an important requirement in asynchronous communication networks, where devices transmit short data packets in an unscheduled fashion. Such a synchronization is typically achieved by means of a preamble sent in front of the data packet. In this paper, we study fast burst synchronization for power line communication (PLC systems operating below 500 kHz and transmitting data rates of up to about 500 kbps as it is typical in various PLC network applications. In particular, we are concerned with the receiver processing of the preamble signal and the actual design of preambles suitable for fast burst synchronization in such PLC systems. Our approach is comprehensive in that it takes into account the most distinctive characteristics of the power line channel, which are multipath propagation, highly varying path loss, and disturbance by impulse noise, as well as important practical constraints, especially the need for spectral shaping of the preamble signal and fast adjustment of the automatic gain control (AGC. In fact, we regard the explicit incorporation of these various requirements into the preamble design as the main contribution of this work. We devise an optimization criterion and a stochastic algorithm to search for suitable preamble sequences. A comprehensive performance comparison of a designed and two conventional preambles shows that the designed sequence is superior in terms of (a fast burst synchronization in various transmission environments, (b fast AGC adjustment, and (c compliance of its spectrum with the spectral mask applied to the data transmit signal.

CODE STEM - Moon, Mars, and Beyond; DLESE-Powered On-Line Classroom, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — "CODE (COrps DEvelopment) STEM (Science, Technology, Engineering, and Math) ? Moon Mars and Beyond; DLESE-Powered On-Line Classroom" shares the excitement of...

Bird on the wire: Landscape planning considering costs and benefits for bird populations coexisting with power lines.

Science.gov (United States)

D'Amico, Marcello; Catry, Inês; Martins, Ricardo C; Ascensão, Fernando; Barrientos, Rafael; Moreira, Francisco

2018-02-24

Power-line grids are increasingly expanding worldwide, as well as their negative impacts on avifauna, namely the direct mortality through collision and electrocution, the reduction of breeding performance, and the barrier effect. On the other hand, some bird species can apparently benefit from the presence of power lines, for example perching for hunting purposes or nesting on electricity towers. In this perspective essay, we reviewed the scientific literature on both costs and benefits for avifauna coexisting with power lines. Overall, we detected a generalized lack of studies focusing on these costs or benefits at a population level. We suggest that a switch in research approach to a larger spatio-temporal scale would greatly improve our knowledge about the actual effects of power lines on bird populations. This research approach would facilitate suitable landscape planning encompassing both mitigation of costs and promotion of benefits for bird populations coexisting with power lines. For example, the strategic route planning of electricity infrastructures would limit collision risk or barrier effects for threatened bird populations. Concurrently, this strategic route planning would promote the range expansion of threatened populations of other bird species, by providing nesting structures in treeless but potentially suitable landscapes. We suggest establishing a collaborative dialogue among the scientific community, governments, and electricity companies, with the aim to produce a win-win scenario in which both biodiversity conservation and infrastructure development are integrated in a common strategy.

Experience and development of on-line BWR surveillance system at Onagawa nuclear power station unit-1

International Nuclear Information System (INIS)

Kishi, A.; Chiba, K.; Kato, K.; Ebata, S.; Ando, Y.; Sakamoto, H.

1986-01-01

ONAGAWA nuclear power station Unit-1 (Tohoku Electric Power Co.) is a BWR-4 nuclear power station of 524 MW electric power which started commercial operation in June 1984. To attain high reliability and applicability for ONAGAWA-1, Tohoku Electric Power Co. and Toshiba started a Research and Development project on plant surveillance and diagnosis from April 1982. Main purposes of this project are to: (1) Develop an on-line surveillance system and acquire its operating experience at a commercial BWR, (2) Assist in plant operation and maintenance by data acquisition and analysis, (3) Develop a new technique for plant surveillance and diagnosis. An outline of the project, operating experience gained from the on-line surveillance system and an introduction to new diagnosis techniques are reported in this paper. (author)

Trend on High-speed Power Line Communication Technology

Science.gov (United States)

Ogawa, Osamu

High-speed power line communication (PLC) is useful technology to easily build the communication networks, because construction of new infrastructure is not necessary. In Europe and America, PLC has been used for broadband networks since the beginning of 21th century. In Japan, high-speed PLC was deregulated only indoor usage in 2006. Afterward it has been widely used for home area network, LAN in hotels and school buildings and so on. And recently, PLC is greatly concerned as communication technology for smart grid network. In this paper, the author surveys the high-speed PLC technology and its current status.

Adaptive settings of distance relay for MOV-protected series compensated line with distributed capacitance considering wind power

Science.gov (United States)

Sivov, Oleg Viktorovich

Series compensated lines are protected from overvoltage by metal-oxide-varistors (MOVs) connected in parallel with the capacitor bank. The nonlinear characteristics of MOV devices add complexity to fault analysis and distance protection operation. During faults, the impedance of the line is modified by an equivalent impedance of the parallel MOV/capacitor circuit, which affects the distance protection. The intermittent wind generation introduces additional complexity to the system performance and distance protection. Wind variation affects the fault current level and equivalent MOV/capacitor impedance during a fault, and hence the distance relay operation. This thesis studies the impact of the intermittent wind power generation on the operation of MOV during faults. For the purpose of simulation, an equivalent wind farm model is proposed to generate a wind generation profile using wind farm generation from California independent system operator (ISO) as a guide for wind power variation to perform the study. The IEEE 12-bus test system is modified to include MOV-protected series capacitor and the equivalent wind farm model. The modified test system is simulated in the MATLAB/Simulink environment. The study has been achieved considering three phase and single line to ground (SLG) faults on the series compensated line to show the effect of wind variation on the MOV operation. This thesis proposes an adaptive setting method for the mho relay distance protection of series compensated line considering effects of wind power variation and MOV operation. The distributed parameters of a transmission line are taken into account to avoid overreaching and underreaching of distance relays. The study shows that variable wind power affects system power flow and fault current in the compensated line during a fault which affects the operation of MOVs for different fault conditions. The equivalent per-phase impedance of the MOV/capacitor circuit has an effect on the system operation

Measurement of magnetic fields in the direct proximity of power line conductors

International Nuclear Information System (INIS)

Mamishev, A.V.; Russell, B.D.

1995-01-01

Modeling and managing of power frequency magnetic fields requires verification of theory with actual measurements. Measurements only at ground level are not always sufficient for comprehensive studies. The technique and the results of three-dimensional mapping of the power frequency magnetic fields high above ground level are presented in this paper. Comparative calculations illustrate relevance and approximations of the existing theoretical approach to field modeling. The influence of harmonics on the elliptical rotation of the magnetic field vector is illustrated. The possibility of use of the magnetic fields for the power line proximity detection is discussed

METHODICAL APPROACHES TO THE CHOICE OF THE NEW GENERATION OF HIGH-VOLTAGE POWER TRANSMISSION LINE 220 kV OPTIONS

Directory of Open Access Journals (Sweden)

POSTOLATI V.M.

2010-08-01

Full Text Available The Transmission Power Lines of new generation are described in the article (single- compact, double-circuit compact, double-circuit Controlled Self-compensating High Voltage Transmission Power Lines (CSHVL. Basic principles of creation, design elements and comparative characteristics of the transmission lines of the new generation are described, the advantages of its are showed. Methodical approaches to the choosing of a new generation of transmission lines and facilities management FACTS are formulated. Methodical approaches to the choice of options for transmission lines 220 kV and facilities management are shown.

LED-Based High-Voltage Lines Warning System

Directory of Open Access Journals (Sweden)

Eldar MUSA

2013-04-01

Full Text Available LED-based system, running with the current of high-voltage lines and converting the current flowing through the line into the light by using a toroid transformer, has been developed. The transformer’s primary winding is constituted by the high voltage power line. Toroidal core consists of two equal parts and the secondary windings are evenly placed on these two parts. The system is mounted on the high-voltage lines as a clamp. The secondary winding ends are connected in series by the connector on the clamp. LEDs are supplied by the voltage at the ends of secondary. Current flowing through highvoltage transmission lines is converted to voltage by the toroidal transformer and the light emitting LEDs are supplied with this voltage. The theory of the conversion of the current flowing through the line into the light is given. The system, running with the current of the line and converting the current into the light, has been developed. System has many application areas such as warning high voltage lines (warning winches to not hinder the high-voltage lines when working under the lines, warning planes to not touch the high-voltage lines, remote measurement of high-voltage line currents, and local illumination of the line area

Line impedance estimation using model based identification technique

DEFF Research Database (Denmark)

Ciobotaru, Mihai; Agelidis, Vassilios; Teodorescu, Remus

2011-01-01

The estimation of the line impedance can be used by the control of numerous grid-connected systems, such as active filters, islanding detection techniques, non-linear current controllers, detection of the on/off grid operation mode. Therefore, estimating the line impedance can add extra functions...... into the operation of the grid-connected power converters. This paper describes a quasi passive method for estimating the line impedance of the distribution electricity network. The method uses the model based identification technique to obtain the resistive and inductive parts of the line impedance. The quasi...

Electromagnetic interference produced by power or electrified railway lines on metallic pipe networks

International Nuclear Information System (INIS)

Lucca, G.

1999-01-01

The paper presents an algorithm for the calculation, in the frequency domain, of the induced voltages and currents on a generic metallic pipe network exposed to the electromagnetic interference from a power line or an electrified railway line. By assuming as known the voltages and the currents on the inducing line, the algorithm may be subdivided into the following main steps: a) determination of the ideal electromotive force and current generators to be applied to the induced structure in order to represent the electromagnetic influence from the inducing line; b) modelling of the pipe network by means of a suitable equivalent electric network; c) calculation of voltages and currents on the induced network [it

Sizes of flaring kernels in various parts of the Hα line profile

Directory of Open Access Journals (Sweden)

K. Radziszewski

2008-10-01

Full Text Available In this paper we present new results of spectra-photometrical investigations of the flaring kernels' sizes and their intensities measured simultaneously in various parts of the Hα line profile. Our investigations were based on the very high temporal resolution spectral-imaging observations of the solar flares collected with Large Coronagraph (LC, Multi-channel Subtractive Double Pass Spectrograph and Solar Eclipse Coronal Imaging System (MSDP-SECIS at Białkow Observatory (University of Wrocław, Poland.

We have found that the areas of the investigated individual flaring kernels vary in time and in wavelengths, as well as the intensities and areas of the Hα flaring kernels decreased systematically when observed in consecutive wavelengths toward the wings of the Hα line. Our result could be explained as an effect of the cone-shaped lower parts of the magnetic loops channeling high energy particle beams exciting chromospheric plasma.

Developing maximal neuromuscular power: part 2 - training considerations for improving maximal power production.

Science.gov (United States)

Cormie, Prue; McGuigan, Michael R; Newton, Robert U

2011-02-01

This series of reviews focuses on the most important neuromuscular function in many sport performances: the ability to generate maximal muscular power. Part 1, published in an earlier issue of Sports Medicine, focused on the factors that affect maximal power production while part 2 explores the practical application of these findings by reviewing the scientific literature relevant to the development of training programmes that most effectively enhance maximal power production. The ability to generate maximal power during complex motor skills is of paramount importance to successful athletic performance across many sports. A crucial issue faced by scientists and coaches is the development of effective and efficient training programmes that improve maximal power production in dynamic, multi-joint movements. Such training is referred to as 'power training' for the purposes of this review. Although further research is required in order to gain a deeper understanding of the optimal training techniques for maximizing power in complex, sports-specific movements and the precise mechanisms underlying adaptation, several key conclusions can be drawn from this review. First, a fundamental relationship exists between strength and power, which dictates that an individual cannot possess a high level of power without first being relatively strong. Thus, enhancing and maintaining maximal strength is essential when considering the long-term development of power. Second, consideration of movement pattern, load and velocity specificity is essential when designing power training programmes. Ballistic, plyometric and weightlifting exercises can be used effectively as primary exercises within a power training programme that enhances maximal power. The loads applied to these exercises will depend on the specific requirements of each particular sport and the type of movement being trained. The use of ballistic exercises with loads ranging from 0% to 50% of one-repetition maximum (1RM) and

Improving the Power Quality in Tehran Metro Line-Two Using the Ant Colony Algorithm

Directory of Open Access Journals (Sweden)

H. Ehteshami

2017-12-01

Full Text Available This research aims to survey the improvement of power quality in Tehran metro line 2 using the ant colony algorithm and to investigate all the factors affecting the achievement of this goal. In order to put Tehran on the road of sustainable development, finding a solution for dealing with air pollution is essential. The use of public transportation, especially metro, is one of the ways to achieve this goal. Since the highest share of pollutants in Tehran belongs to cars and mobile sources, relative statistical indicators are estimated through assuming the effect of metro lines development and subsequently reduction of traffic on power quality index.

High power test of RF window and coaxial line in vacuum

International Nuclear Information System (INIS)

Sun, D.; Champion, M.; Gormley, M.; Kerns, Q.; Koepke, K.; Moretti, A.

1993-01-01

Primary rf input couplers for the superconducting accelerating cavities of the TESLA electron linear accelerator test to be performed at DESY, Hamburg, Germany are under development at both DESY and Fermilab. The input couplers consist of a WR650 waveguide to coaxial line transition with an integral ceramic window, a coaxial connection to the superconducting accelerating cavity with a second ceramic window located at the liquid nitrogen heat intercept location, and bellows on both sides of the cold window to allow for cavity motion during cooldown, coupling adjustments and easier assembly. To permit in situ high peak power processing of the TESLA superconducting accelerating cavities, the input couplers are designed to transmit nominally 1 ms long, 2 MW peak, 1.3 GHz rf pulses from the WR650 waveguide at room temperature to the cavities at 1.8 K. The coaxial part of the Fermilab TESLA input coupler design has been tested up to 1.7 MW using the prototype 805 MHz rf source located at the A0 service building of the Tevatron. The rf source, the testing system and the test results are described

Adapting AC Lines to DC Grids for Large-Scale Renewable Power Transmission

Directory of Open Access Journals (Sweden)

D. Marene Larruskain

2014-10-01

Full Text Available All over the world, governments of different countries are nowadays promoting the use of clean energies in order to achieve sustainable energy systems. In this scenario, since the installed capacity is continuously increasing, renewable sources can play an important role. Notwithstanding that, some important problems may appear when connecting these sources to the grid, being the overload of distribution lines one of the most relevant. In fact, renewable generation is usually connected to the nearest AC grid, although this HV system may not have been designed considering distributed generation. In the particular case of large wind farms, the electrical grid has to transmit all the power generated by wind energy and, as a consequence, the AC system may get overloaded. It is therefore necessary to determine the impact of wind power transmission so that appropriate measures can be taken. Not only are these measures influenced by the amount of power transmitted, but also by the quality of the transmitted power, due to the output voltage fluctuation caused by the highly variable nature of wind. When designing a power grid, although AC systems are usually the most economical solution because of its highly proven technology, HVDC may arise in some cases (e.g. offshore wind farms as an interesting alternative, offering some added values such as lower losses and better controllability. This way, HVDC technology can solve most of the aforementioned problems and has a good potential for future use. Additionally, the fast development of power electronics based on new and powerful semiconductor devices allow the spread of innovative technologies, such as VSC-HVDC, which can be applied to create DC grids. This paper focuses on the main aspects involved in adapting the existing overhead AC lines to DC grids, with the objective of improving the transmission of distributed renewable energy to the centers of consumption.

Impedance-Source Networks for Electric Power Conversion Part II

DEFF Research Database (Denmark)

Siwakoti, Yam P.; Peng, Fang Zheng; Blaabjerg, Frede

2015-01-01

Impedance-source networks cover the entire spectrum of electric power conversion applications (dc-dc, dc-ac, ac-dc, ac-ac) controlled and modulated by different modulation strategies to generate the desired dc or ac voltage and current at the output. A comprehensive review of various impedance......-source-network-based power converters has been covered in a previous paper and main topologies were discussed from an application point of view. Now Part II provides a comprehensive review of the most popular control and modulation strategies for impedance-source network-based power converters/inverters. These methods...

Overvoltage and Insulation Coordination of Overhead Lines in Multiple-Terminal MMC-HVDC Link for Wind Power Delivery

Directory of Open Access Journals (Sweden)

Huiwen He

2017-01-01

Full Text Available The voltage-sourced converter-based HVDC link, including the modular multilevel converter (MMC configuration, is suitable for wind power, photovoltaic energy, and other kinds of new energy delivery and grid-connection. Current studies are focused on the MMC principles and controls and few studies have been done on the overvoltage of transmission line for the MMC-HVDC link. The main reason is that environmental factors have little effect on DC cables and the single-phase/pole fault rate is low. But if the cables were replaced by the overhead lines, although the construction cost of the project would be greatly reduced, the single-pole ground fault rate would be much higher. This paper analyzed the main overvoltage types in multiple-terminal MMC-HVDC network which transmit electric power by overhead lines. Based on ±500 kV multiple-terminal MMC-HVDC for wind power delivery project, the transient simulation model was built and the overvoltage types mentioned above were studied. The results showed that the most serious overvoltage was on the healthy adjacent line of the faulty line caused by the fault clearing of DC breaker. Then the insulation coordination for overhead lines was conducted according to the overvoltage level. The recommended clearance values were given.

Wireless Sensor Network for Electric Transmission Line Monitoring

Energy Technology Data Exchange (ETDEWEB)

Alphenaar, Bruce

2009-06-30

Generally, federal agencies tasked to oversee power grid reliability are dependent on data from grid infrastructure owners and operators in order to obtain a basic level of situational awareness. Since there are many owners and operators involved in the day-to-day functioning of the power grid, the task of accessing, aggregating and analyzing grid information from these sources is not a trivial one. Seemingly basic tasks such as synchronizing data timestamps between many different data providers and sources can be difficult as evidenced during the post-event analysis of the August 2003 blackout. In this project we investigate the efficacy and cost effectiveness of deploying a network of wireless power line monitoring devices as a method of independently monitoring key parts of the power grid as a complement to the data which is currently available to federal agencies from grid system operators. Such a network is modeled on proprietary power line monitoring technologies and networks invented, developed and deployed by Genscape, a Louisville, Kentucky based real-time energy information provider. Genscape measures transmission line power flow using measurements of electromagnetic fields under overhead high voltage transmission power lines in the United States and Europe. Opportunities for optimization of the commercial power line monitoring technology were investigated in this project to enable lower power consumption, lower cost and improvements to measurement methodologies. These optimizations were performed in order to better enable the use of wireless transmission line monitors in large network deployments (perhaps covering several thousand power lines) for federal situational awareness needs. Power consumption and cost reduction were addressed by developing a power line monitor using a low power, low cost wireless telemetry platform known as the ''Mote''. Motes were first developed as smart sensor nodes in wireless mesh networking applications

On-line tuning of a fuzzy-logic power system stabilizer

International Nuclear Information System (INIS)

Hossein-Zadeh, N.; Kalam, A.

2002-01-01

A scheme for on-line tuning of a fuzzy-logic power system stabilizer is presented. firstly, a fuzzy-logic power system stabilizer is developed using speed deviation and accelerating power as the controller input variables. The inference mechanism of fuzzy-logic controller is represented by a decision table, constructed of linguistic IF-THEN rules. The Linguistic rules are available from experts and the design procedure is based on these rules. It assumed that an exact model of the plant is not available and it is difficult to extract the exact parameters of the power plant. Thus, the design procedure can not be based on an exact model. This is an advantage of fuzzy logic that makes the design of a controller possible without knowing the exact model of the plant. Secondly, two scaling parameters are introduced to tune the fuzzy-logic power system stabilizer. These scaling parameters are the outputs of another fuzzy-logic system, which gets the operating conditions of power system as inputs. These mechanism of tuning the fuzzy-logic power system stabilizer makes the fuzzy-logic power system stabilizer adaptive to changes in the operating conditions. Therefore, the degradation of the system response, under a wide range of operating conditions, is less compared to the system response with a fixed-parameter fuzzy-logic power system stabilizer and a conventional (linear) power system stabilizer. The tuned stabilizer has been tested by performing nonlinear simulations using a synchronous machine-infinite bus model. The responses are compared with a fixed parameters fuzzy-logic power system stabilizer and a conventional (linear) power system stabilizer. It is shown that the tuned fuzzy-logic power system stabilizer is superior to both of them

On-line transient stability assessment of large-scale power systems by using ball vector machines

International Nuclear Information System (INIS)

Mohammadi, M.; Gharehpetian, G.B.

2010-01-01

In this paper ball vector machine (BVM) has been used for on-line transient stability assessment of large-scale power systems. To classify the system transient security status, a BVM has been trained for all contingencies. The proposed BVM based security assessment algorithm has very small training time and space in comparison with artificial neural networks (ANN), support vector machines (SVM) and other machine learning based algorithms. In addition, the proposed algorithm has less support vectors (SV) and therefore is faster than existing algorithms for on-line applications. One of the main points, to apply a machine learning method is feature selection. In this paper, a new Decision Tree (DT) based feature selection technique has been presented. The proposed BVM based algorithm has been applied to New England 39-bus power system. The simulation results show the effectiveness and the stability of the proposed method for on-line transient stability assessment procedure of large-scale power system. The proposed feature selection algorithm has been compared with different feature selection algorithms. The simulation results demonstrate the effectiveness of the proposed feature algorithm.

Power Swing Detection in UPFC-Compensated Line by Phase Angle of Current

DEFF Research Database (Denmark)

Khodaparast, Jalal; Khederzadeh, M.; Silva, Filipe Miguel Faria da

2017-01-01

Power swing blocker (PSB) is a complementary part of distance relay protection, that detects power swing, in order to prevent unintended operation of a distance relay. Unified power flow controller (UPFC) is used in power system to control both active and reactive powers and its operation during...... condition. The results show that these indices may no longer work in systems with UPFC. In addition, this paper proposes a new method for detecting power swing based on the phase angle of current at relay point and compares it with two other methods. The new method distinguishes power swing from a fault...

Effect of voltage sags on digitally controlled line connected switched-mode power supplies

DEFF Research Database (Denmark)

Török, Lajos; Munk-Nielsen, Stig

2012-01-01

Different voltage disorders like voltage fluctuations, sags, frequency variations may occur in the power supply networks due to different fault conditions. These deviations from normal operation affects in different ways the line connected devices. Standards were developed to protect and ensure...... of voltage sags is analyzed. Fault tolerant control algorithm was designed, implemented and is discussed. The fault conditions and their effects were investigated at different power levels....

Application of Coordinated SOFC and SMES Robust Control for Stabilizing Tie-Line Power

Energy Technology Data Exchange (ETDEWEB)

Ning Zhang; Wei Gu; Haojun Yu; Wei Liu [School of Electrical Engineering, Southeast University, Nanjing (China)

2013-04-15

Wind power causes fluctuations in power systems and introduces issues concerning system stability and power quality because of the lack of controllability of its discontinuous and intermittent resources. This paper presents a coordinated control strategy for solid oxide fuel cells (SOFCs) and superconducting magnetic energy storage (SMES) to match the intermittent wind power generation and compensate for the rapid load changes. An optimal H{sub {infinity}}control method, where the weighting function selection is expressed as an optimization problem, is proposed to mitigate tie-line power fluctuations and the mixed-sensitivity approach is used to deal with the interference suppression. Simulation results show that the proposed method significantly improves the smoothing effect of wind power fluctuations. Compared with the conventional control method, the proposed method has better anti-interference performance in various operating situations.

Application of Coordinated SOFC and SMES Robust Control for Stabilizing Tie-Line Power

Directory of Open Access Journals (Sweden)

Wei Liu

2013-04-01

Full Text Available Wind power causes fluctuations in power systems and introduces issues concerning system stability and power quality because of the lack of controllability of its discontinuous and intermittent resources. This paper presents a coordinated control strategy for solid oxide fuel cells (SOFCs and superconducting magnetic energy storage (SMES to match the intermittent wind power generation and compensate for the rapid load changes. An optimal H∞ control method, where the weighting function selection is expressed as an optimization problem, is proposed to mitigate tie-line power fluctuations and the mixed-sensitivity approach is used to deal with the interference suppression. Simulation results show that the proposed method significantly improves the smoothing effect of wind power fluctuations. Compared with the conventional control method, the proposed method has better anti-interference performance in various operating situations.

Alleviation SSR and Low Frequency Power Oscillations in Series Compensated Transmission Line using SVC Supplementary Controllers

Science.gov (United States)

Kumar, Sanjiv; Kumar, Narendra

2017-06-01

In this work, supplementary sub-synchronous damping controllers (SSDC) are proposed for damping sub-synchronous oscillations in power systems with series compensated transmission lines. Series compensation have extensively been used as effective means of increasing the power transfer capability of a transmission lines and improving transient stability limits of power systems. Series compensation with transmission lines may cause sub-synchronous resonance (SSR). The eigenvalue investigation tool is used to ascertain the existence of SSR. It is shown that the addition of supplementary controller is able to stabilize all unstable modes for T-network model. Eigenvalue investigation and time domain transient simulation of detailed nonlinear system are considered to investigate the performance of the controllers. The efficacies of the suggested supplementary controllers are compared on the IEEE first benchmark model for computer simulations of SSR by means of time domain simulation in Matlab/Simulink environment. Supplementary SSDC are considered in order to compare effectiveness of SSDC during higher loading in alleviating the small signal stability problem.

Lightning current distribution to ground at a power line tower carrying a radio base station

NARCIS (Netherlands)

Grcev, L.; Deursen, van A.P.J.; Waes, van J.B.M.

2005-01-01

Radio base stations are often mounted on towers of power transmission lines. They are usually powered from the low-voltage network through an isolating transformer, to separate the high- and low-voltage networks. The isolating transformer ensures security at customers' premises in the case of nearby

Markerless tracking in nuclear power plants. A line segment-based approach

International Nuclear Information System (INIS)

Ishii, Hirotake; Kimura, Taro; Tokumaru, Hiroki; Shimoda, Hiroshi; Koda, Yuya

2017-01-01

To develop augmented reality-based support systems, a tracking method that measures the camera's position and orientation in real time is indispensable. A relocalization is one step that is used to (re)start the tracking. A line-segment-based relocalization method that uses a RGB-D camera and coarse-to-fine approach was developed and evaluated for this study. In the preparation stage, the target environment is scanned with a RGB-D camera. Line segments are recognized. Then three-dimensional positions of the line segments are calculated, and statistics of the line segments are calculated and stored in a database. In the relocalization stage, a few images that closely resemble the current RGB-D camera image are chosen from the database by comparing the statistics of the line segments. Then the most similar image is chosen using Normalized Cross-Correlation. This coarse-to-fine approach reduces the computational load to find the most similar image. The method was evaluated in the water purification room of the Fugen nuclear power plant. Results showed that the success rate of the relocalization is 93.6% and processing time is 45.7 ms per frame on average, which is promising for practical use. (author)

Automated Inventory Control System for Nigeria Power Holding

African Journals Online (AJOL)

PROF. O. E. OSUAGWU

2013-09-01

Sep 1, 2013 ... Power Holding Company of Nigeria (PHCN) currently holds in excess of millions in spare parts inventory ... equipment/utilities at all times in view of stochastic item ... line contingency and small conductor sizing lines which are ...

A Three-Part Electricity Price Mechanism for Photovoltaic-Battery Energy Storage Power Plants Considering the Power Quality and Ancillary Service

Directory of Open Access Journals (Sweden)

Yajing Gao

2017-08-01

Full Text Available To solve the problem of solar abandoning, which is accompanied by the rapid development of photovoltaic (PV power generation, a demonstration of a photovoltaic-battery energy storage system (PV-BESS power plant has been constructed in Qinghai province in China. However, it is difficult for the PV-BESS power plant to survive and develop with the current electricity price mechanism and subsidy policy. In this paper, a three-part electricity price mechanism is proposed based on a deep analysis of the construction and operation costs and economic income. The on-grid electricity price is divided into three parts: the capacity price, graded electricity price, and ancillary service price. First, to ensure that the investment of the PV-BESS power plant would achieve the industry benchmark income, the capacity price and benchmark electricity price are calculated using the discounted cash flow method. Then, the graded electricity price is calculated according to the grade of the quality of grid-connected power. Finally, the ancillary service price is calculated based on the graded electricity price and ancillary service compensation. The case studies verify the validity of the three-part electricity price mechanism. The verification shows that the three-part electricity price mechanism can help PV-BESS power plants to obtain good economic returns, which can promote the development of PV-BESS power plants.

Converging cylindrical magnetohydrodynamic shock collapse onto a power-law-varying line current

KAUST Repository

Mostert, W.; Pullin, D. I.; Samtaney, Ravi; Wheatley, V.

2016-01-01

We investigate the convergence behaviour of a cylindrical, fast magnetohydrodynamic (MHD) shock wave in a neutrally ionized gas collapsing onto an axial line current that generates a power law in time, azimuthal magnetic field. The analysis is done

A fast, robust algorithm for power line interference cancellation in neural recording

Science.gov (United States)

Keshtkaran, Mohammad Reza; Yang, Zhi

2014-04-01

Objective. Power line interference may severely corrupt neural recordings at 50/60 Hz and harmonic frequencies. The interference is usually non-stationary and can vary in frequency, amplitude and phase. To retrieve the gamma-band oscillations at the contaminated frequencies, it is desired to remove the interference without compromising the actual neural signals at the interference frequency bands. In this paper, we present a robust and computationally efficient algorithm for removing power line interference from neural recordings. Approach. The algorithm includes four steps. First, an adaptive notch filter is used to estimate the fundamental frequency of the interference. Subsequently, based on the estimated frequency, harmonics are generated by using discrete-time oscillators, and then the amplitude and phase of each harmonic are estimated by using a modified recursive least squares algorithm. Finally, the estimated interference is subtracted from the recorded data. Main results. The algorithm does not require any reference signal, and can track the frequency, phase and amplitude of each harmonic. When benchmarked with other popular approaches, our algorithm performs better in terms of noise immunity, convergence speed and output signal-to-noise ratio (SNR). While minimally affecting the signal bands of interest, the algorithm consistently yields fast convergence (30 dB) in different conditions of interference strengths (input SNR from -30 to 30 dB), power line frequencies (45-65 Hz) and phase and amplitude drifts. In addition, the algorithm features a straightforward parameter adjustment since the parameters are independent of the input SNR, input signal power and the sampling rate. A hardware prototype was fabricated in a 65 nm CMOS process and tested. Software implementation of the algorithm has been made available for open access at https://github.com/mrezak/removePLI. Significance. The proposed algorithm features a highly robust operation, fast adaptation to

Impulsive Noise Characterization in Narrowband Power Line Communication

Directory of Open Access Journals (Sweden)

Li Bai

2018-04-01

Full Text Available Currently, narrowband Power line communication (PLC is considered an attractive communication system in smart grid environments for applications such as advanced metering infrastructure (AMI. In this paper, we will present a comprehensive comparison and analysis in time and frequency domain of noise measured in China and Italy. In addition, impulsive noise in these two countries are mainly analyzed and modeled using two probability based models, Middleton Class A (MCA model and α stable distribution model. The results prove that noise measured in China is rich in impulsive noise, and can be modeled well by α stable distribution model, while noise measured in Italy has less impulsive noise, and can be better modeled by the MCA model.

A guide: sale of power opportunities for distributed generators. Part B. The guide

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

This report is Part B of a series of three produced to help prospective distributed generators familiarise themselves with the electricity market in Great Britain (England, Scotland and Wales) and to assist potential generators to identify options for the sale of their electrical output. Part A is an introductory guide and Part C lists sources of further information, useful contact details and a glossary. Part B covers the key issues in some depth and is designed for those with some background knowledge. It examines: the electricity supply industry in Great Britain including the physical and commercial electricity supply chains and the commercial arrangements for trading; the legislative framework including networks, price controls, licensing and exemptions; the value of power produced by small generators including factors affecting the value of power, wholesale market value, Renewables Obligation Certificates (ROCs), Climate Change Levy exemption certificates and the EU Emissions Trading Scheme; options for the sale of power including market trading, supplier and consolidator contracts, exempt and licensed supply, and finance; and the costs and benefits of power sales options including the initial and ongoing costs of selling power.

Wideband Impulse Modulation and Receiver Algorithms for Multiuser Power Line Communications

Directory of Open Access Journals (Sweden)

Andrea M. Tonello

2007-01-01

Full Text Available We consider a bit-interleaved coded wideband impulse-modulated system for power line communications. Impulse modulation is combined with direct-sequence code-division multiple access (DS-CDMA to obtain a form of orthogonal modulation and to multiplex the users. We focus on the receiver signal processing algorithms and derive a maximum likelihood frequency-domain detector that takes into account the presence of impulse noise as well as the intercode interference (ICI and the multiple-access interference (MAI that are generated by the frequency-selective power line channel. To reduce complexity, we propose several simplified frequency-domain receiver algorithms with different complexity and performance. We address the problem of the practical estimation of the channel frequency response as well as the estimation of the correlation of the ICI-MAI-plus-noise that is needed in the detection metric. To improve the estimators performance, a simple hard feedback from the channel decoder is also used. Simulation results show that the scheme provides robust performance as a result of spreading the symbol energy both in frequency (through the wideband pulse and in time (through the spreading code and the bit-interleaved convolutional code.

Conducted Interference Immunity Characteristics to High-speed Power Line Communication System

Science.gov (United States)

Tokuda, Masamitsu; Hosoya, Satoshi; Yamagata, Toru; Matsuo, Takashi

In this paper, we measured the immunity characteristics to the conducted interference wave, from the aspect of PHY rate (physical layer data rate) of PLC (Power Line Communication) system, and compared with simulation results by MATLAB/ Simulink. When the interference signal is impressed to the OFDM (Orthogonal Frequency Division Multiplexing) signal, the PHY rate decrease rapidly below C/I (Carrier / Interference) = 25dB and become nearly zero around C/I = -35dB, and so it turns out that the PLC System with OFDM signal has a good narrowband interference immunity characteristic. In addition, it is revealed that the PHY rate of PLC modem can be calculated by MATLAB/Simulink even when the narrowband interference signal is impressed through the power line. Furthermore, we examined the improving effect of the notch band for the immunity characteristics to the conducted interference wave. As a result, it is revealed that the PHY rate normalized by the maximum value increases by 15∼25% by inserting the notch when impressing the interference signal in the notch band and C/I is improved by 10∼15dB by inserting the notch.

Inventory Control of Spare Parts for Operating Nuclear Power plants

Energy Technology Data Exchange (ETDEWEB)

Park, Jong-Hyuck; Jang, Se-Jin; Hwang, Eui-Youp; Yoo, Sung-Soo; Yoo, Keun-Bae; Lee, Sang-Guk; Hong, Sung-Yull [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

2006-07-01

Inventory control of spare parts plays an increasingly important role in operation management. The trade-off is clear: on one hand a large number of spare parts ties up a large amount of capital, while on the other hand too little inventory may result in extremely costly emergency actions. This is why during the last few decades inventory of spare parts control has been the topics of many publications. Recently management systems such as manufacturing resources planning (MRP) and enterprise resource planning (ERP) have been added. However, most of these contributions have similar theoretical background. This means the concepts and techniques are mainly based on mathematical assumptions and modeling inventory of spare parts situations Nuclear utilities in Korea have several problems to manage the optimum level of spare parts though they used MRP System. Because most of items have long lead time and they are imported from United States, Canada, France and so on. In this paper, we will examine the available inventory optimization models which are applicable to nuclear power plant and then select optimum model and assumptions to make inventory of spare parts strategies. Then we develop the computer program to select and determine optimum level of spare parts which should be automatically controlled by KHNP ERP system. The main contribution of this paper is an inventory of spare parts control model development, which can be applied to nuclear power plants in Korea.

Inventory Control of Spare Parts for Operating Nuclear Power plants

International Nuclear Information System (INIS)

Park, Jong-Hyuck; Jang, Se-Jin; Hwang, Eui-Youp; Yoo, Sung-Soo; Yoo, Keun-Bae; Lee, Sang-Guk; Hong, Sung-Yull

2006-01-01

Inventory control of spare parts plays an increasingly important role in operation management. The trade-off is clear: on one hand a large number of spare parts ties up a large amount of capital, while on the other hand too little inventory may result in extremely costly emergency actions. This is why during the last few decades inventory of spare parts control has been the topics of many publications. Recently management systems such as manufacturing resources planning (MRP) and enterprise resource planning (ERP) have been added. However, most of these contributions have similar theoretical background. This means the concepts and techniques are mainly based on mathematical assumptions and modeling inventory of spare parts situations Nuclear utilities in Korea have several problems to manage the optimum level of spare parts though they used MRP System. Because most of items have long lead time and they are imported from United States, Canada, France and so on. In this paper, we will examine the available inventory optimization models which are applicable to nuclear power plant and then select optimum model and assumptions to make inventory of spare parts strategies. Then we develop the computer program to select and determine optimum level of spare parts which should be automatically controlled by KHNP ERP system. The main contribution of this paper is an inventory of spare parts control model development, which can be applied to nuclear power plants in Korea

A guide: Sale of power opportunities for distributed generators. Part A: the summary

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

A lengthy guide has been written for the benefit of prospective distributed generators for the electric power market in Great Britain. The growing range of generation methods and the government's emissions reduction programme were the reasons for the study. The document consists of three parts. Part A is an introductory guide for distributed generators in Britain, Part B is a guide to the sale of power opportunities in Britain, and Part C gives additional information. The guide represents a basic but high-level overview of the sale of electric power but anyone with a serious interest in the subject matter is advised to also seek professional help before embarking on an expensive or long-term project. The guide was prepared by SOHN Associates under contract to the DTI.

Transmission line pulse system for avalanche characterization of high power semiconductor devices

Science.gov (United States)

Riccio, Michele; Ascione, Giovanni; De Falco, Giuseppe; Maresca, Luca; De Laurentis, Martina; Irace, Andrea; Breglio, Giovanni

2013-05-01

Because of the increasing in power density of electronic devices for medium and high power application, reliabilty of these devices is of great interest. Understanding the avalanche behaviour of a power device has become very important in these last years because it gives an indication of the maximum energy ratings which can be seen as an index of the device ruggedness. A good description of this behaviour is given by the static IV blocking characteristc. In order to avoid self heating, very relevant in high power devices, very short pulses of current have to be used, whose value can change from few milliamps up to tens of amps. The most used method to generate short pulses is the TLP (Transmission Line Pulse) test, which is based on charging the equivalent capacitance of a transmission line to high value of voltage and subsequently discharging it onto a load. This circuit let to obtain very short square pulses but it is mostly used for evaluate the ESD capability of semiconductor and, in this environment, it generates pulses of low amplitude which are not high enough to characterize the avalanche behaviour of high power devices . Advanced TLP circuit able to generate high current are usually very expensive and often suffer of distorption of the output pulse. In this article is proposed a simple, low cost circuit, based on a boosted-TLP configuration, which is capable to produce very square pulses of about one hundreds of nanosecond with amplitude up to some tens of amps. A prototype is implemented which can produce pulses up to 20A of amplitude with 200 ns of duration which can characterize power devices up to 1600V of breakdown voltage. Usage of microcontroller based logic make the circuit very flexible. Results of SPICE simulation are provided, together with experimental results. To prove the effectiveness of the circuit, the I-V blocking characteristics of two commercial devices, namely a 600V PowerMOS and a 1200V Trench-IGBT, are measured at different

Generation of data base for on-line fatigue life monitoring of Indian nuclear power plant components: Part I - Generation of Green's functions for end fitting

International Nuclear Information System (INIS)

Mukhopadhyay, N.K.; Dutta, B.K.; Kushwaha, H.S.

1994-01-01

Green's function technique is the heart of the on- line fatigue monitoring methodology. The plant transients are converted to stress and temperature response using this technique. To implement this methodology in a nuclear power plant, Green's functions are to be generated in advance. For structures of complex geometries, Green's functions are to be stored in a data base to convert on-line, the plant data to temperature/stress response, using a personal computer. End fitting, end shield, pressurizer, steam generator tube sheet are few such components of PHWR where fatigue monitoring is needed. In the present paper, Green's functions are generated for end fitting of a 235 MWe Indian PHWR using finite element method. End fitting has been analysed using both 3-D and 2-D (axisymmetric) finite element models. Temperature and stress Green's functions are generated at few critical locations using the code ABAQUS. (author). 10 refs., 11 figs

Reports in the area sensor technology: Part 2: Dynamic deviations which may appear via the sensing lines in measurement of reactor pressure and level

International Nuclear Information System (INIS)

Bergdahl, Bengt-Goeran

2002-12-01

The sensors are part of the safety system in a nuclear power plant. They are the first link in a chain of components, which affect the safety system. It is therefore of great importance that the sensors fulfil tough requirements on reliability and response time. In practice, the dynamic qualities of the sensors in a BWR are seldom, or never, tested. The static qualities, on the other hand, are controlled every year when the transmitters are calibrated. This is done during the regular outage of the power plant. It is common that several sensors are connected to the same sensing line. This is true especially in old reactors, where only a few pressure taps are available in the reactor pressure vessel. This is a troublesome disadvantage in the design, since a failure in one sensing line will affect all components, which are connected to that sensing line ('Common Cause Failure'). This report focuses on deviations in the measurement system connected to the sensing lines. The deviations are illustrated by examples from Swedish and foreign BWRs. The sensing lines are mechanically passive components. They can reduce a system's response time even if there are now deviations in the static presentation. This report mentions cases in nuclear power plants, where the time constant of the sensing line has changed from 0.1 seconds, which is a normal response time, to 5 seconds. This has happened because of a gradual blockage of the sensing line. Today, signal analysis is the only way to examine the dynamic qualities of sensing lines. Filtrations can be unveiled by measuring and analysing the transmitter signal, regardless the location of the filtration: in the sensing line, in the transmitter or in other instrumentation components. A practical case is presented where pulsation dampers with so-called needles were used at Ringhals 1 in Sweden. Their influence on the response time for the measurement signal corresponds to a time constant = 0.55 s. By eliminating the needles the

Social class, political power, and the state: their implications in medicine--part III.

Science.gov (United States)

Navarro, V

1977-01-01

This is the third part of an article on the distribution of power and the nature of the state in Western industrialized societies and their implications in medicine. Parts I and II were published in the preceding issue of this Journal. Part I presented a critique of contemporary theories of the Western system of power; discussed the countervailing pluralist and power of elite theories, as well as those of bureaucratic and professional control; and concluded with an examination of the Marxist theories of economic determinism, structural determinism, and corporate statism. Part II presented a Marxist theory of the role, nature, and characteristics of state intervention. Part III focuses on the mode of that intervention and the reasons for its growth, with an added analysis of the attributes of state intervention in the health sector, and of the dialectical relationship between its growth and the current fiscal crisis of the state. In all three parts, the focus is on Western European countries and on North America, with many examples and categories from the area of medicine.

AUTOMATED INSPECTION OF POWER LINE CORRIDORS TO MEASURE VEGETATION UNDERCUT USING UAV-BASED IMAGES

Directory of Open Access Journals (Sweden)

M. Maurer

2017-08-01

Full Text Available Power line corridor inspection is a time consuming task that is performed mostly manually. As the development of UAVs made huge progress in recent years, and photogrammetric computer vision systems became well established, it is time to further automate inspection tasks. In this paper we present an automated processing pipeline to inspect vegetation undercuts of power line corridors. For this, the area of inspection is reconstructed, geo-referenced, semantically segmented and inter class distance measurements are calculated. The presented pipeline performs an automated selection of the proper 3D reconstruction method for on the one hand wiry (power line, and on the other hand solid objects (surrounding. The automated selection is realized by performing pixel-wise semantic segmentation of the input images using a Fully Convolutional Neural Network. Due to the geo-referenced semantic 3D reconstructions a documentation of areas where maintenance work has to be performed is inherently included in the distance measurements and can be extracted easily. We evaluate the influence of the semantic segmentation according to the 3D reconstruction and show that the automated semantic separation in wiry and dense objects of the 3D reconstruction routine improves the quality of the vegetation undercut inspection. We show the generalization of the semantic segmentation to datasets acquired using different acquisition routines and to varied seasons in time.

Automated Inspection of Power Line Corridors to Measure Vegetation Undercut Using Uav-Based Images

Science.gov (United States)

Maurer, M.; Hofer, M.; Fraundorfer, F.; Bischof, H.

2017-08-01

Power line corridor inspection is a time consuming task that is performed mostly manually. As the development of UAVs made huge progress in recent years, and photogrammetric computer vision systems became well established, it is time to further automate inspection tasks. In this paper we present an automated processing pipeline to inspect vegetation undercuts of power line corridors. For this, the area of inspection is reconstructed, geo-referenced, semantically segmented and inter class distance measurements are calculated. The presented pipeline performs an automated selection of the proper 3D reconstruction method for on the one hand wiry (power line), and on the other hand solid objects (surrounding). The automated selection is realized by performing pixel-wise semantic segmentation of the input images using a Fully Convolutional Neural Network. Due to the geo-referenced semantic 3D reconstructions a documentation of areas where maintenance work has to be performed is inherently included in the distance measurements and can be extracted easily. We evaluate the influence of the semantic segmentation according to the 3D reconstruction and show that the automated semantic separation in wiry and dense objects of the 3D reconstruction routine improves the quality of the vegetation undercut inspection. We show the generalization of the semantic segmentation to datasets acquired using different acquisition routines and to varied seasons in time.

Wireless Power Transfer System for Rotary Parts Telemetry of Gas Turbine Engine

Directory of Open Access Journals (Sweden)

Xiaoming He

2018-04-01

Full Text Available A novel wireless power transfer approach for the rotary parts telemetry of a gas turbine engine is proposed. The advantages of a wireless power transfer (WPT system in the power supply for the rotary parts telemetry of a gas turbine engine are introduced. By simplifying the circuit of the inductively-coupled WPT system and developing its equivalent circuit model, the mathematical expressions of transfer efficiency and transfer power of the system are derived. A mutual inductance model between receiving and transmitting coils of the WPT system is presented and studied. According to this model, the mutual inductance between the receiving and the transmitting coils can be calculated at different axial distances. Then, the transfer efficiency and transfer power can be calculated as well. Based on the test data, the relationship of the different distances between the two coils, the transfer efficiency, and transfer power is derived. The proper positions where the receiving and transmitting coils are installed in a gas turbine engine are determined under conditions of satisfying the transfer efficiency and transfer power that the telemetry system required.

Corona Onset Characteristics of Bundle Conductors in UHV AC Power Lines at 2200 m Altitude

Directory of Open Access Journals (Sweden)

Shilong Huang

2018-04-01

Full Text Available The corona onset characteristic of bundle conductors is an important limiting factor for the design of UHV AC power lines in high-altitude areas. An experimental study on the corona characteristics of 8 × LGJ630, 6 × LGJ720, 8 × LGJ720 and 10 × LGJ720 bundle conductors commonly used in UHV power lines under dry and wet conductor conditions, as well as artificial moderate and heavy rain conditions, was conducted in Ping’an County, Xining City (elevation 2200 m. By using the tangent line method, the corona onset voltages and onset electric field of four types of conductors at high altitudes are obtained for the first time. In addition, the calculation model of corona onset voltage considering the outer strands’ effect on the electric field and the geometric factor in the corona cage in high altitude areas is established. The comparison of the calculation results and experimental results under dry conditions verifies the model’s correctness. Based on the results, an optimal selection scheme for high altitudes is proposed. The roughness coefficient was also calculated and analysed: the roughness coefficient of bundled conductors was between 0.59 and 0.77, and the roughness coefficient of the wet conductor was between the dry and rainy conditions. Both the experimental data and the calculation model can provide a reference for conductor selection for UHV AC power lines for use in high-altitude areas.

Wireless Power Supply via Coupled Magnetic Resonance for on-line Monitoring Wireless Sensor of High-voltage Electrical Equipment

DEFF Research Database (Denmark)

Xingkui, Mao; Qisheng, Huang; Yudi, Xiao

2016-01-01

On-line monitoring of high-voltage electrical equipment (HV-EE) aiming to detect faults effectively has become crucial to avoid serious accidents. Moreover, highly reliable power supplies are the key component for the wireless sensors equipped in such on-line monitoring systems. Therefore......, in this paper, the wireless power supply via coupled magnetic resonance (MR-WPS) is proposed for powering the wireless sensor and the associated wireless sensor solution is also proposed. The key specifications of the MR-WPS working in switchgear cabinet with a harsh operation environment are analyzed...... power is able to be delivered to the wireless sensor through the designed MR-WPS, and therefore the theoretical analysis and design is verified....

Nuclear power plant diagnostic system

International Nuclear Information System (INIS)

Prokop, K.; Volavy, J.

1982-01-01

Basic information is presented on diagnostic systems used at nuclear power plants with PWR reactors. They include systems used at the Novovoronezh nuclear power plant in the USSR, at the Nord power plant in the GDR, the system developed at the Hungarian VEIKI institute, the system used at the V-1 nuclear power plant at Jaslovske Bohunice in Czechoslovakia and systems of the Rockwell International company used in US nuclear power plants. These diagnostic systems are basically founded on monitoring vibrations and noise, loose parts, pressure pulsations, neutron noise, coolant leaks and acoustic emissions. The Rockwell International system represents a complex unit whose advantage is the on-line evaluation of signals which gives certain instructions for the given situation directly to the operator. The other described systems process signals using similar methods. Digitized signals only serve off-line computer analyses. (Z.M.)

Control of single-phase islanded PV/battery minigrids based on power-line signaling

DEFF Research Database (Denmark)

Quintana, Pablo; Guerrero, Josep M.; Dragicevic, Tomislav

2014-01-01

should be utilized as efficiently as possible. This paper proposes a coordinated control strategy based on power-line signaling (PLS), instead of common communications, for a single-phase minigrid in which each unit can operate in different operation modes taking into account the resource limitation...... types of renewable energy sources (RES) and energy storage systems (ESS). Specifically, the recharging process of secondary battery, the most prominent ESS, should be done in a specific manner to preserve its life-time, microgrid line voltage must be kept within the bounds and the energy offered by RES...

Review of the first line supervisory positions in nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Mullin, D; Mackenzie, C W [Hickling Corp. (Canada)

1995-10-01

The authors review the nature of the tasks performed by first line maintenance supervisors in three nuclear power plants. They compare these tasks to core supervisory training curriculum, supervisory job descriptions, and both the process related to performance appraisals, and the criteria applied in carrying out these performance evaluations. Recommendations have been made concerning methods of increasing the relevancy of training and improving the performance appraisal process. ( author). 5 figs.

Review of the first line supervisory positions in nuclear power plants

International Nuclear Information System (INIS)

Mullin, D.; Mackenzie, C.W.

1995-10-01

The authors review the nature of the tasks performed by first line maintenance supervisors in three nuclear power plants. They compare these tasks to core supervisory training curriculum, supervisory job descriptions, and both the process related to performance appraisals, and the criteria applied in carrying out these performance evaluations. Recommendations have been made concerning methods of increasing the relevancy of training and improving the performance appraisal process. ( author). 5 figs

Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part B: Application on a Case Study

Directory of Open Access Journals (Sweden)

Angelo La Seta

2016-05-01

Full Text Available Organic Rankine cycle (ORC power systems have recently emerged as promising solutions for waste heat recovery in low- and medium-size power plants. Their performance and economic feasibility strongly depend on the expander. The design process and efficiency estimation are particularly challenging due to the peculiar physical properties of the working fluid and the gas-dynamic phenomena occurring in the machine. Unlike steam Rankine and Brayton engines, organic Rankine cycle expanders combine small enthalpy drops with large expansion ratios. These features yield turbine designs with few highly-loaded stages in supersonic flow regimes. Part A of this two-part paper has presented the implementation and validation of the simulation tool TURAX, which provides the optimal preliminary design of single-stage axial-flow turbines. The authors have also presented a sensitivity analysis on the decision variables affecting the turbine design. Part B of this two-part paper presents the first application of a design method where the thermodynamic cycle optimization is combined with calculations of the maximum expander performance using the mean-line design tool described in part A. The high computational cost of the turbine optimization is tackled by building a model which gives the optimal preliminary design of an axial-flow turbine as a function of the cycle conditions. This allows for estimating the optimal expander performance for each operating condition of interest. The test case is the preliminary design of an organic Rankine cycle turbogenerator to increase the overall energy efficiency of an offshore platform. For an increase in expander pressure ratio from 10 to 35, the results indicate up to 10% point reduction in expander performance. This corresponds to a relative reduction in net power output of 8.3% compared to the case when the turbine efficiency is assumed to be 80%. This work also demonstrates that this approach can support the plant designer

THROUGH-THE-EARTH (TTE) COMMUNICATIONS SYSTEM AND THE IN-MINE POWER LINE (IMPL) COMMUNICATIONS SYSTEM

International Nuclear Information System (INIS)

Zvi H. Meiksin

2002-01-01

Work has progressed on both subsystems: the Through-the-Earth (TTE) Communications system and the In-Mine Power Line (IMPL) Communications system. The TTE system: The system was fabricated and repackaged as an industrial product enclosed in a commercial rugged, waterproof housing suitable for installation in mines. Features were added to the system to appeal to the preferences of different mine managers. Arrangements were made with NIOSH to install the system in the Lake Lynn underground mine for evaluation and demonstration to potential users. The IMPL system: Voice compression was successfully implemented and incorporated into the laboratory model. Compressed voice was transmitted through a power line, expanded at the receiving end, and received with high clarity

Facts and feelings: Framing effects in responses to uncertainties about high-voltage power lines

OpenAIRE

de Vries, G.; de Bruijn, J.A.

2017-01-01

To ensure power supply security, electricity transmission system operators (TSOs) have to upscale high-voltage overhead power lines. However, upscaling frequently meets opposition. Opposition can be caused by uncertainties about risks and benefits and might lead to costly delays (Linder, 1995; Wiedemann, Boerner,& Claus, 2016). To minimize opposition, TSOs and related public services need to respond to these uncertainties in a credible and convincing (effective) way. Effective risk commun...

The Power Behind the Controversy: Understanding Local Policy Elites' Perceptions on the Benefits and Risks Associated with High Voltage Power Line Installation in the State of Arkansas

Science.gov (United States)

Moyer, Rachael M.

Following a proposal for the installation of high voltage power lines in northwest Arkansas, a controversial policy debate emerged. Proponents of the transmission line argue that such an installation is inevitable and necessary to efficiently and reliably support the identified electric load in the region. Opponents claim that the lines will degrade the natural environment and hamper the tourism-based local economy in affected regions, notably in Ozark Mountain areas. This study seeks to understand how local policy elites perceive the benefits and risks associated with proposed transmission lines, which is a critical step in comprehending the formation and changes of related government policies. First, based upon the dual process theory of judgment, this study systematically investigates the triadic relationships between (a) more profound personal value predispositions, (b) affects and feelings, and (c) perceived benefits and risks related to the proposed installation of high voltage power lines among local policy elites in the state of Arkansas. Next, this study focuses more specifically on the role of value predispositions, specific emotional dimensions of affect heuristics, and perceptions pertaining to high voltage power line risks and benefits. Using original data collected from a statewide Internet survey of 420 local leaders and key policymakers about their opinions on the related issues, other factors claimed by previous literature, including trust, knowledge level, and demographic characteristics are considered. Analytical results suggest that grid-group cultural predispositions, as deeply held core values within local policy elites' individual belief systems, both directly and indirectly -- through affective feelings -- shape perceived utility associated with the installation of high voltage power lines. Recognizing that risk perceptions factor into policy decisions, some practical considerations for better designing policy addressing controversial issues

Strategic provisioning of replacement parts for CANDU power plants

International Nuclear Information System (INIS)

Mizuno, G.; Tume, P.; Prentice, J.

2000-01-01

Provisioning of replacement parts and management of critical spares are key factors in optimizing maintenance programs for CANDU power plants. With a view to supply assurance, Atomic Energy Canada Limited (AECL) has created a Spare Parts Branch (SPB) to provide a clear pipeline from the client to the delivered replacement part(s). SPB provides the client with assured access to a qualified supplier database, computer aided design, engineering and manufacturing services and material upgrades and design registration through the authorized inspection agency. The AECL spare parts strategic provisioning service plan that has four thrusts: 1) the efficient delivery of cost-effective replacement parts; 2) obsolete parts resolution; 3) a website that will provide our clients with real-time access to replacement part data; and 4) inventory recovery opportunities. Thrusts one and two are actively ensuring plant maintenance for on-shore and off-shore CANDU clients. Thrusts three and four are longer-term commitments. This paper will explore these thrusts in the context of our CANDU business practices. (author)

Fuji Electric`s line of uninterruptible power systems; Muteiden dengen sochi no seihin keiretsu

Energy Technology Data Exchange (ETDEWEB)

Kobata, S.; Ishikawa, Y.; Yokoyama, T. [Fuji Electric Co. Ltd., Tokyo (Japan)

1997-08-10

Uninterruptible power systems (UPSs) are widely used in financial institutions, utility services, totalizator systems, traffic control systems, plants, new media, medical systems, and information processing services. These are highly reliable power supply systems to protect computer-aided information and communication systems from power failure or defects. Described herein is the company`s line of UPSs developed by integrating power electronics, and digital and high-frequency switching techniques. The major components of a UPS are rectifier, inverter and battery. Power is supplied by commercial or inverter system. The former is widely used by plants because of its low loss and high efficiency, although distorted output waves or instantaneous power failure may occur when the power source is switched in the case of power failure. The latter is suited for computer systems, because of its ability of stably supplying power, without being affected by the disturbances which may occur in the commercial system. 7 figs., 2 tabs.

Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A

DEFF Research Database (Denmark)

Meroni, Andrea; La Seta, Angelo; Andreasen, Jesper Graa

2016-01-01

Axial-flow turbines represent a well-established technology for a wide variety of power generation systems. Compactness, flexibility, reliability and high efficiency have been key factors for the extensive use of axial turbines in conventional power plants and, in the last decades, in organic...... Rankine cycle power systems. In this two-part paper, an overall cycle model and a model of an axial turbine were combined in order to provide a comprehensive preliminary design of the organic Rankine cycle unit, taking into account both cycle and turbine optimal designs. Part A presents the preliminary...

On-line calibration of process instrumentation channels in nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Hashemian, H.M.; Farmer, J.P. [Analysis and Measurement Services Corp., Knoxville, TN (United States)

1995-04-01

An on-line instrumentation monitoring system was developed and validated for use in nuclear power plants. This system continuously monitors the calibration status of instrument channels and determines whether or not they require manual calibrations. This is accomplished by comparing the output of each instrument channel to an estimate of the process it is monitoring. If the deviation of the instrument channel from the process estimate is greater than an allowable limit, then the instrument is said to be {open_quotes}out of calibration{close_quotes} and manual adjustments are made to correct the calibration. The success of the on-line monitoring system depends on the accuracy of the process estimation. The system described in this paper incorporates both simple intercomparison techniques as well as analytical approaches in the form of data-driven empirical modeling to estimate the process. On-line testing of the calibration of process instrumentation channels will reduce the number of manual calibrations currently performed, thereby reducing both costs to utilities and radiation exposure to plant personnel.

Effects of power-line construction on wetland vegetation in Massachusetts, USA

Science.gov (United States)

Nickerson, Norton H.; Dobberteen, Ross A.; Jarman, Nancy M.

1989-07-01

Utility rights-of-way corridors through wetland areas generate long-term impacts from construction activities to these valuable ecosystems. Changes to and recovery of the vegetation communities of a cattail marsh, wooded swamp, and shrub/bog wetland were documented through measurements made each growing season for two years prior, five years following, and again on the tenth year after construction of a 345-kV transmission line. While both the cattail marsh and wooded swamp recovered within a few years, measures of plant community composition in the shrub/bog wetland were still lower, compared to controls, after ten years. Long-term investigations such as the one reported here help decrease uncertainty and provide valuable information for future decision making regarding construction of power utility lines through valuable and dwindling wetland resources.

An experimental investigation into power broadening of the Na-D lines in a flame

International Nuclear Information System (INIS)

Calcar, R.A. van.

1980-01-01

Investigations are described aimed at the verification of the existence of power broadening in fluorescence, as predicted by theory in the case of a broadband excitation source. Measurements were performed on a vapour of sodium (Na) atoms in a pre-mixed H 2 -O 2 -Ar flame under 1 atm pressure. The easily excited first resonance (or D) lines of Na were chosen for the observation of power broadening in fluorescence. (Auth.)

MCD 80: A modular coupling system for power line carrier transmission

Energy Technology Data Exchange (ETDEWEB)

Fischer, B; Mayer, M

1983-05-01

Power line carrier (PLC) links are of great importance to power supply utilities. The communications equipment is linked to the H.V. system by a coupling device. Brown Boveri have developed a new modular coupling system MCD 80 which is compact, programmable and economical. The benefit of years of experience in the field went into its development. With the new system, optimum PLC couplings, R.F. through-connections and junction networks are possible for all H.V. transmission systems. A general look at the subject of PLC couplings is followed by a closer look at the main components, such as the programmable high pass coupling unit, band pass coupling unit, hybrid, separating filter, R.F. junction network and attenuator. Some typical examples are described.

Assessment of ELF magnetic fields produced by independent power lines

International Nuclear Information System (INIS)

Lucca, G.

2008-01-01

In this paper, the problem of assessing the ELF (extremely low-frequency) magnetic fields produced, in a certain area characterised by the presence of more than one independent power line, is faced. The use of the incoherent summation of the single contributions, as an advantageous estimator of the total magnetic field, is proposed and justified by means of a heuristic procedure. This kind of approach can be seen as a useful and practical tool to be employed in environmental impact analysis and in assessing long-term human exposure to ELF magnetic fields. (authors)

On estimation of reliability for pipe lines of heat power plants under cyclic loading

International Nuclear Information System (INIS)

Verezemskij, V.G.

1986-01-01

One of the possible methods to obtain a quantitative estimate of the reliability for pipe lines of the welded heat power plants under cyclic loading due to heating-cooling and due to vibration is considered. Reliability estimate is carried out for a common case of loading by simultaneous cycles with different amplitudes and loading asymmetry. It is shown that scattering of the breaking number of cycles for the metal of welds may perceptibly decrease reliability of the welded pipe line

On-line validation of feedwater flow rate in nuclear power plants using neural networks

International Nuclear Information System (INIS)

Khadem, M.; Ipakchi, A.; Alexandro, F.J.; Colley, R.W.

1994-01-01

On-line calibration of feedwater flow rate measurement in nuclear power plants provides a continuous realistic value of feedwater flow rate. It also reduces the manpower required for periodic calibration needed due to the fouling and defouling of the venturi meter surface condition. This paper presents a method for on-line validation of feedwater flow rate in nuclear power plants. The method is an improvement of the previously developed method which is based on the use of a set of process variables dynamically related to the feedwater flow rate. The online measurements of this set of variables are used as inputs to a neural network to obtain an estimate of the feedwater flow rate reading. The difference between the on-line feedwater flow rate reading, and the neural network estimate establishes whether there is a need to apply a correction factor to the feedwater flow rate measurement for calculation of the actual reactor power. The method was applied to the feedwater flow meters in the two feedwater flow loops of the TMI-1 nuclear power plant. The venturi meters used for flow measurements are susceptible to frequent fouling that degrades their measurement accuracy. The fouling effects can cause an inaccuracy of up to 3% relative error in feedwater flow rate reading. A neural network, whose inputs were the readings of a set of reference instruments, was designed to predict both feedwater flow rates simultaneously. A multi-layer feedforward neural network employing the backpropagation algorithm was used. A number of neural network training tests were performed to obtain an optimum filtering technique of the input/output data of the neural networks. The result of the selection of the filtering technique was confirmed by numerous Fast Fourier Transform (FFT) tests. Training and testing were done on data from TMI-1 nuclear power plant. The results show that the neural network can predict the correct flow rates with an absolute relative error of less than 2%

Trends in on-line data processing

International Nuclear Information System (INIS)

Masetti, M.

1981-01-01

The developement of integrated circuits has been characterized by an exponential growth of gates on a single chip that will still continue in the coming years. In parallel the price per bit is dropping down with more or less the same law. As a consequence of this a few statements can be made: The present 16-bit minicomputer in a small configuration is going to be substituted by a 16-bit microcomputer, and the 16-bit microcomputer in a powerful configuration by a 32-bit midi having also a virtual memory facility. Fully programmable or microcoded powerful devices like the LASS hardware processor or MICE, will allow an efficient on-line filter. Higher computing speed can be achieved by a multiprocessor configuration which can be insensitive to hardware failures. Therefore we are moving towards an integrated on-line computing system with much higher computing power than now and the present distinction between on-line and off-line will no longer be so sharp. As more processing can be performed on-line, fast high quality feed-back can be provided for the experiment. In the years to come the trend towards more processing power, at a lower price, and assembled in the same hardware volume will continue for at least five years; at the same time the future large high-energy physics experiments at LEP will be carried out within a wide international collaboration. In this environment methods must be found for a large fraction of the work to be distributed amongst the collaborators. To accomplish this aim it is necessary to introduce common standard practices concerning both hardware and software, in such a way that the seperate parts, developed by the collaborators, will be plug-compatible. (orig.)

A new algorithm for optimum voltage and reactive power control for minimizing transmission lines losses

International Nuclear Information System (INIS)

Ghoudjehbaklou, H.; Danai, B.

2001-01-01

Reactive power dispatch for voltage profile modification has been of interest to power utilities. Usually local bus voltages can be altered by changing generator voltages, reactive shunts, ULTC transformers and SVCs. Determination of optimum values for control parameters, however, is not simple for modern power system networks. Heuristic and rather intelligent algorithms have to be sought. In this paper a new algorithm is proposed that is based on a variant of a genetic algorithm combined with simulated annealing updates. In this algorithm a fuzzy multi-objective a approach is used for the fitness function of the genetic algorithm. This fuzzy multi-objective function can efficiently modify the voltage profile in order to minimize transmission lines losses, thus reducing the operating costs. The reason for such a combination is to utilize the best characteristics of each method and overcome their deficiencies. The proposed algorithm is much faster than the classical genetic algorithm and cna be easily integrated into existing power utilities software. The proposed algorithm is tested on an actual system model of 1284 buses, 799 lines, 1175 fixed and ULTC transformers, 86 generators, 181 controllable shunts and 425 loads

Spare parts management for nuclear power generation facilities

Science.gov (United States)

Scala, Natalie Michele

With deregulation, utilities in the power sector face a much more urgent imperative to emphasize cost efficiencies as compared to the days of regulation. One major opportunity for cost savings is through reductions in spare parts inventories. Most utilities are accustomed to carrying large volumes of expensive, relatively slow-moving parts because of a high degree of risk-averseness. This attitude towards risk is rooted in the days of regulation. Under regulation, companies recovered capital inventory costs by incorporating them into the base rate charged to their customers. In a deregulated environment, cost recovery is no longer guaranteed. Companies must therefore reexamine their risk profile and develop policies for spare parts inventory that are appropriate for a competitive business environment. This research studies the spare parts inventory management problem in the context of electric utilities, with a focus on nuclear power. It addresses three issues related to this problem: criticality, risk, and policy. With respect to criticality and risk, a methodology is presented that incorporates the use of influence diagrams and the Analytic Hierarchy Process (AHP). A new method is developed for group aggregation in the AHP when Saaty and Vargas' (2007) dispersion test fails and decision makers are unwilling or unable to revise their judgments. With respect to policy, a quantitative model that ranks the importance of keeping a part in inventory and recommends a corresponding stocking policy through the use of numerical simulation is developed. This methodology and its corresponding models will enable utilities that have transitioned from a regulated to a deregulated environment become more competitive in their operations while maintaining safety and reliability standards. Furthermore, the methodology developed is general enough so that other utility plants, especially those in the nuclear sector, will be able to use this approach. In addition to regulated

''High-power microwave'' tubes: In the laboratory and on-line

International Nuclear Information System (INIS)

Caryotakis, G.

1994-01-01

The possibility of incapacitating the electronic circuits of hostile equipment with high-energy microwave pulses has created a demand for microwave tubes capable of very high peak pulsed powers. Experimentalists, primarily from the plasma physics community, have been working in this field, dubbed High-Power Microwave or HPM. Separately, research in high-energy physics requires electron-positron colliders with energies approaching 1 trillion electron-volts (1 terra-electron-volt, or TeV). Such accelerators must be powered by microwave sources that are very similar to some that are proposed for the HPM application. The paper points out that for these tubes to be used on-line in the manner intended, they must be designed and built to operate at a very high internal vacuum, which is not the case for many of the HPM laboratory projects. The development of a particular klystron at the Stanford Linear Accelerator Center is described in detail in order to illustrate the need for special facilities and strong Quality Control. Should the Defense requirements for HPM survive the end of the cold war, an effort should be made to coordinate the tube development activities serving these two widely disparate applications

Impact evaluation of conducted UWB transients on loads in power-line networks

Science.gov (United States)

Li, Bing; Månsson, Daniel

2017-09-01

Nowadays, faced with the ever-increasing dependence on diverse electronic devices and systems, the proliferation of potential electromagnetic interference (EMI) becomes a critical threat for reliable operation. A typical issue is the electronics working reliably in power-line networks when exposed to electromagnetic environment. In this paper, we consider a conducted ultra-wideband (UWB) disturbance, as an example of intentional electromagnetic interference (IEMI) source, and perform the impact evaluation at the loads in a network. With the aid of fast Fourier transform (FFT), the UWB transient is characterized in the frequency domain. Based on a modified Baum-Liu-Tesche (BLT) method, the EMI received at the loads, with complex impedance, is computed. Through inverse FFT (IFFT), we obtain time-domain responses of the loads. To evaluate the impact on loads, we employ five common, but important quantifiers, i.e., time-domain peak, total signal energy, peak signal power, peak time rate of change and peak time integral of the pulse. Moreover, to perform a comprehensive analysis, we also investigate the effects of the attributes (capacitive, resistive, or inductive) of other loads connected to the network, the rise time and pulse width of the UWB transient, and the lengths of power lines. It is seen that, for the loads distributed in a network, the impact evaluation of IEMI should be based on the characteristics of the IEMI source, and the network features, such as load impedances, layout, and characteristics of cables.

Deep convolutional neural network processing of aerial stereo imagery to monitor vulnerable zones near power lines

Science.gov (United States)

Qayyum, Abdul; Saad, Naufal M.; Kamel, Nidal; Malik, Aamir Saeed

2018-01-01

The monitoring of vegetation near high-voltage transmission power lines and poles is tedious. Blackouts present a huge challenge to power distribution companies and often occur due to tree growth in hilly and rural areas. There are numerous methods of monitoring hazardous overgrowth that are expensive and time-consuming. Accurate estimation of tree and vegetation heights near power poles can prevent the disruption of power transmission in vulnerable zones. This paper presents a cost-effective approach based on a convolutional neural network (CNN) algorithm to compute the height (depth maps) of objects proximal to power poles and transmission lines. The proposed CNN extracts and classifies features by employing convolutional pooling inputs to fully connected data layers that capture prominent features from stereo image patches. Unmanned aerial vehicle or satellite stereo image datasets can thus provide a feasible and cost-effective approach that identifies threat levels based on height and distance estimations of hazardous vegetation and other objects. Results were compared with extant disparity map estimation techniques, such as graph cut, dynamic programming, belief propagation, and area-based methods. The proposed method achieved an accuracy rate of 90%.

Evaluation on the model of performance predictions for on-line monitoring system for combined-cycle power plant

International Nuclear Information System (INIS)

Kim, Si Moon

2002-01-01

This paper presents the simulation model developed to predict design and off-design performance of an actual combined cycle power plant(S-Station in Korea), which would be running combined with on-line performance monitoring system in an on-line real-time fashion. The first step in thermal performance analysis is to build an accurate performance model of the power plant, in order to achieve this goal, GateCycle program has been employed in developing the model. This developed models predict design and off-design performance with a precision of one percent over a wide range of operating conditions so that on-line real-time performance monitoring can accurately establish both current performance and expected performance and also help the operator identify problems before they would be noticed

Magnet power supply control of the NSLS VUV and x-ray storage rings transfer lines

International Nuclear Information System (INIS)

Klein, J.D.; Ramamoorthy, S.; Singh, O.; Smith, J.D.

1985-01-01

The transfer lines for NSLS VUV and x-ray storage rings have been split. New power supplies have been incorporated with existing ones. The existing microprocessor system has been upgraded in order to control the additional functions. This system expands the input/output port of the microprocessor to an addressable serial/parallel link to each magnet power supply. The implementation of this system will be discussed

Kosovo’s Ground Flash Density and Protection of Transmission Lines of the Kosovo Power System from Atmospheric Discharges

Directory of Open Access Journals (Sweden)

Bahri Prebreza

2018-03-01

Full Text Available In this paper is presented the protection of transmission power lines of the Kosovo Power System from atmospheric discharges, with the use of surge arresters. Atmospheric discharges represent one of the main causes of interruptions for the Kosovo Power System. In addition, the ground flash density for Kosovo is given. The transmission lines with the worst performance regarding atmospheric discharges are discussed in more detail and are presented recommendations about the surge arresters used to protect the system from these overvoltages. The data provided by the localized lightning system in Kosovo enable us to provide a detailed correlation of the reported outages of the Kosovo Power System and corresponding atmospheric discharges. Recommendations for protection in terms of surge arresters are given followed by subsequent dynamic simulations using MATLAB software.

Assembly delay line pulse generators

CERN Multimedia

CERN PhotoLab

1971-01-01

Assembly of six of the ten delay line pulse generators that will power the ten kicker magnet modules. One modulator part contains two pulse generators. Capacitors, inductances, and voltage dividers are in the oil tank on the left. Triggered high-pressure spark gap switches are on the platforms on the right. High voltage pulse cables to the kicker magnet emerge under the spark gaps. In the centre background are the assembled master gaps.

Power Line Interference Removal from Electrocardiogram Using a Simplified Lattice Based Adaptive IIR Notch Filter

National Research Council Canada - National Science Library

Dhillon, Santpal

2001-01-01

...) notch filter with a simplified adaptation algorithm for removal of power line frequency from ECG signals, The performance of this filter is better as compared to a second order infinite impulse response (IIR...

Formulation, computation and improvement of steady state security margins in power systems. Part II: Results

International Nuclear Information System (INIS)

Echavarren, F.M.; Lobato, E.; Rouco, L.; Gomez, T.

2011-01-01

A steady state security margin for a particular operating point can be defined as the distance from this initial point to the secure operating limits of the system. Four of the most used steady state security margins are the power flow feasibility margin, the contingency feasibility margin, the load margin to voltage collapse, and the total transfer capability between system areas. This is the second part of a two part paper. Part I has proposed a novel framework of a general model able to formulate, compute and improve any steady state security margin. In Part II the performance of the general model is validated by solving a variety of practical situations in modern real power systems. Actual examples of the Spanish power system will be used for this purpose. The same computation and improvement algorithms outlined in Part I have been applied for the four security margins considered in the study, outlining the convenience of defining a general framework valid for the four of them. The general model is used here in Part II to compute and improve: (a) the power flow feasibility margin (assessing the influence of the reactive power generation limits in the Spanish power system), (b) the contingency feasibility margin (assessing the influence of transmission and generation capacity in maintaining a correct voltage profile), (c) the load margin to voltage collapse (assessing the location and quantity of loads that must be shed in order to be far away from voltage collapse) and (d) the total transfer capability (assessing the export import pattern of electric power between different areas of the Spanish system). (author)

Formulation, computation and improvement of steady state security margins in power systems. Part II: Results

Energy Technology Data Exchange (ETDEWEB)

Echavarren, F.M.; Lobato, E.; Rouco, L.; Gomez, T. [School of Engineering of Universidad Pontificia Comillas, C/Alberto Aguilera, 23, 28015 Madrid (Spain)

2011-02-15

A steady state security margin for a particular operating point can be defined as the distance from this initial point to the secure operating limits of the system. Four of the most used steady state security margins are the power flow feasibility margin, the contingency feasibility margin, the load margin to voltage collapse, and the total transfer capability between system areas. This is the second part of a two part paper. Part I has proposed a novel framework of a general model able to formulate, compute and improve any steady state security margin. In Part II the performance of the general model is validated by solving a variety of practical situations in modern real power systems. Actual examples of the Spanish power system will be used for this purpose. The same computation and improvement algorithms outlined in Part I have been applied for the four security margins considered in the study, outlining the convenience of defining a general framework valid for the four of them. The general model is used here in Part II to compute and improve: (a) the power flow feasibility margin (assessing the influence of the reactive power generation limits in the Spanish power system), (b) the contingency feasibility margin (assessing the influence of transmission and generation capacity in maintaining a correct voltage profile), (c) the load margin to voltage collapse (assessing the location and quantity of loads that must be shed in order to be far away from voltage collapse) and (d) the total transfer capability (assessing the export import pattern of electric power between different areas of the Spanish system). (author)

Design and development of a high-power, 500 kV pulsed line

International Nuclear Information System (INIS)

Nicolas, A.

A study was made of very high voltage (500 kV) pulse production for 50 ns at half height. A coaxial line was coupled to a Marx generator for obtaining the pulses on an impedance-adapted electron diode. The maximum power obtained was 6.4 x 10 10 W with a current front in the diode of about 30 ns (80 ns pulse length at half height)

Visual impact of overhead power transmission lines and dielectric and corona effects constraints on insulation coordination

International Nuclear Information System (INIS)

Deponti, F.; Fini, G.P.; Porrino, A.; Rosa, F.

1992-06-01

In assessing overhead power transmission line design and planning criteria for the optimization of visual impact, safety and the reduction of electro magnetic disturbance effects, this paper reviews the research findings of ENEL, the Italian Electricity Board. The on-going research activities involve theoretical calculations and laboratory performance tests to determine the best compact configurations for 380 kV lines. The parameters under examination include: insulator spacing, sizing and salt fog resistivity; allowable overvoltages; maximum line length; behaviour in lightning conditions; radio and acoustics disturbances

The Flooding Water Source Analysis following the Feed Line Break at the Compartment outside Containment for Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Song, Dong Soo [Korea Electric Power Research Institute, Daejeon (Korea, Republic of); Park, Young Chan [ACT, Daejeon (Korea, Republic of)

2007-07-01

The Periodic Safety Review(PSR) has been performing for the operating nuclear power plant in Korea. One of the PSR evaluation items is environmental qualification. Flooding issue for nuclear power plants designed and built in 1970 is extremely severe for main steam header compartment and main feed water line region of intermediate building and lower floor. This study presents to analyze flood level of feed water line breaks for the Westinghouse nuclear power plant. This analyses provides the mass and energy releases using the developed methodology for a break outside containment. For the analyses RETRAN-3D computer program is used.

Feasibility study on the interconnection of traction and other power line infrastructures; Machbarkeitsstudie zur Verknuepfung von Bahn- und Energieleitungsinfrastrukturen

Energy Technology Data Exchange (ETDEWEB)

Hofmann, Lutz [Hannover Univ. (Germany). Inst. fuer Energieversorgung und Hochspannungstechnik; Stephan, Arnd [Technische Univ. Dresden (Germany). Professur Elektrische Bahnen; Weyer, Hartmut [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Deutsches und Internationales Berg- und Energierecht

2013-06-15

It was the purpose of the feasibility study to find out if and to what extent the existing transmission route potentials of the 16.7 Hz traction power network (DB Energie GmbH) can be used for the installation of new transmission lines of the standard 50 Hz power supply system. Of importance is here the question if and in which way the integration of new three-phase or DC overhead lines or cable systems in existing traction power routes is technically feasible, and to what extent such interconnection offers a potential for the acceleration of the planning and approval processes. (orig.)

Technical report on levels of electromagnetic fields created by Linky meters. Part 1: laboratory measurements; Part 2: laboratory additional measurements; Part 3: field measurements

International Nuclear Information System (INIS)

2016-05-01

The first part of this study reports measurements of electromagnetic radiations induced by remote-metering reading devices present in new power meters and using the Power-Line Communication (PLC or, in French, CPL) technology, such as the Linky meter. After a recall of legislation regarding exposure to electromagnetic waves, this first part present the two tested meters (Linky of first and third generation, G1 and G3), the performed tests, measurements devices and method. It more precisely reports investigations performed on these both meters, and a comparison with other home appliances. The second part reports additional measurements performed with both meters according to the same methodology, but with the use of a new electric field probe which allows more precise measurements. Maximum electric and magnetic fields have been measured. The third part reports field measurements performed with the same methodology but in dwellings equipped with Linky meters of first generation (G1). Exposure levels have been measured at the vicinity of meters and in other parts of the dwelling

Distance to high-voltage power lines and risk of childhood leukemia--an analysis of confounding by and interaction with other potential risk factors.

Directory of Open Access Journals (Sweden)

Camilla Pedersen

Full Text Available We investigated whether there is an interaction between distance from residence at birth to nearest power line and domestic radon and traffic-related air pollution, respectively, in relation to childhood leukemia risk. Further, we investigated whether adjusting for potential confounders alters the association between distance to nearest power line and childhood leukemia. We included 1024 cases aged <15, diagnosed with leukemia during 1968-1991, from the Danish Cancer Registry and 2048 controls randomly selected from the Danish childhood population and individually matched by gender and year of birth. We used geographical information systems to determine the distance between residence at birth and the nearest 132-400 kV overhead power line. Concentrations of domestic radon and traffic-related air pollution (NOx at the front door were estimated using validated models. We found a statistically significant interaction between distance to nearest power line and domestic radon regarding risk of childhood leukemia (p = 0.01 when using the median radon level as cut-off point but not when using the 75th percentile (p = 0.90. We found no evidence of an interaction between distance to nearest power line and traffic-related air pollution (p = 0.73. We found almost no change in the estimated association between distance to power line and risk of childhood leukemia when adjusting for socioeconomic status of the municipality, urbanization, maternal age, birth order, domestic radon and traffic-related air pollution. The statistically significant interaction between distance to nearest power line and domestic radon was based on few exposed cases and controls and sensitive to the choice of exposure categorization and might, therefore, be due to chance.

Revision of the second basic plans of power reactor development in Power Reactor and Nuclear Fuel Development Corporation

International Nuclear Information System (INIS)

1978-01-01

Revision of the second basic plans concerning power reactor development in PNC (Power Reactor and Nuclear Fuel Development Corporation) is presented. (1) Fast breeder reactors: As for the experimental fast breeder reactor, after reaching the criticality, the power is raised to 50 MW thermal output within fiscal 1978. The prototype fast breeder reactor is intended for the electric output of 200 MW -- 300 MW, using mixed plutonium/uranium oxide fuel. Along the above lines, research and development will be carried out on reactor physics, sodium technology, machinery and parts, nuclear fuel, etc. (2) Advanced thermal reactor: The prototype advanced thermal reactor, with initial fuel primarily of slightly enriched uranium and heavy water moderation and boiling water cooling, of 165 MW electric output, is brought to its normal operation by the end of fiscal 1978. Along the above lines, research and development will be carried out on reactor physics, machinery and parts, nuclear fuel, etc. (Mori, K

Part-task simulator for a WWER-440 nuclear power plant subsystem

International Nuclear Information System (INIS)

Szabo, B.K.

1988-07-01

PC-based part-task simulators for simulating subsystems of nuclear power plants are low cost tools for operator training. In the Central Research Institute for Physics, Budapest, a simulator system has been developed to facilitate fast development of such simulators. The first application simulates the Neutron Flux Monitoring System of WWER-440 nuclear power plants. (author) 9 refs.; 2 figs

Part-task simulator of a WWER-440 type nuclear power plant unit

International Nuclear Information System (INIS)

Palecek, P.

1990-01-01

In the present paper the design of a part-task simulator for WWER-440 type nuclear power plant units by the CEZ (Czech Power Works) Concern is reported. This part-task simulator has been designed for the training of NPP operating personnel. It includes a central computer that is coupled with the training work places and the trainer place. Interchange of information is performed by functional keyboards and semigraphical colour displays. The process is simulated, also in real time scale, on the basis of dynamic models. In addition to the precision of the models used, great importance has primarily been attached to plasticity of information presentation. The part-task simulator may be applied to simulation and demonstration as well as to teaching purposes. The paper presents the achieved state of implementation of the part-task simulator and points out some further stage of evolution. (author)

Mass estimation of loose parts in nuclear power plant based on multiple regression

International Nuclear Information System (INIS)

He, Yuanfeng; Cao, Yanlong; Yang, Jiangxin; Gan, Chunbiao

2012-01-01

According to the application of the Hilbert–Huang transform to the non-stationary signal and the relation between the mass of loose parts in nuclear power plant and corresponding frequency content, a new method for loose part mass estimation based on the marginal Hilbert–Huang spectrum (MHS) and multiple regression is proposed in this paper. The frequency spectrum of a loose part in a nuclear power plant can be expressed by the MHS. The multiple regression model that is constructed by the MHS feature of the impact signals for mass estimation is used to predict the unknown masses of a loose part. A simulated experiment verified that the method is feasible and the errors of the results are acceptable. (paper)

System design of the traction power supply for the high-speed line Beijing - Tianjin

Energy Technology Data Exchange (ETDEWEB)

Altmann, Martin; Fischer, Andreas; Tornow, Torsten [Siemens AG, Erlangen (Germany)

2011-11-15

The high-speed line Beijing - Tianjin connecting the Capital Beijing with the harbour city Tianjin is the first high-speed line in China dedicated only to passenger traffic and is operated at 300 km/h. The commercial service started in due time for the Olympic games in 2008. For the system design and a reliable traction power supply the simulation software Sitras {sup registered} Sidytrac was used. The program incorporates all modules necessary for the overall system design and relating detailed investigations. Measurements during system integration test validated the simulation results. (orig.)

A study on the advanced methods for on-line signal processing by using artificial intelligence in nuclear power plants

International Nuclear Information System (INIS)

Kim, Wan Joo

1993-02-01

In order to assist the operators at the transient states of a nuclear power plant, the automation of signal processing is needed. This study has the objective to process the signals from a nuclear power plant for the purpose of advising the operator. To meet this objective, in this study, two kinds of on-line signal processing system based on AI techniques are developed for the nuclear power plant application with on-line signals. First, an artificial neural network for signal prediction is developed for the adequate countermoves at transient states. The steam generator water level is adopted as the example and the outputs of a simulation program for the dynamics of steam generator combined with noises are used as the training patterns. For the training of the artificial neural network, the modified backpropagation algorithm is proposed for escaping quickly from local minima. The modified algorithm is different from the ordinary backpropagation algorithm in the aspect that the training rate coefficient is repeatedly adjusted randomly and taken when the training is improved. This trial has an effect to search for an adequate magnitude of a training rate coefficient. The comparison result shows that the modified algorithm enables the neural network to be trained more quickly. The simulation result shows that the outputs of the artificial neural network are not sensitive to noises. Using the artificial neural networks proposed in this thesis, the operators can predict the next status of a plant and can take actions to maintain the stability of plant. Second, the multi sensor integration system has been developed for the identification of transient states. The developed system is divided into two parts; pre-processors and a fusion part. An artificial neural network is adopted in the fusion part to include the knowledge about the identification and to make a decision of the transient state. The developed pre-processors play a role of classifying the trend types of

Power Line Communication (PLC) in Space - Current Status and Outlook

Science.gov (United States)

Wolf, J.

2012-05-01

The Power Line Communication (PLC) technology as known from various terrestrial applications, e.g. in building automation, in the automotive sector and on aircraft, appears to be a promising technology for the use on spacecraft. Starting from a critical overview on existing terrestrial PLC applications with their pros and cons, the paper gives a motivation for the introduction of the PLC technology on spacecraft, discusses the potential areas where it can be applied and is highlighting the potential problem areas. A short overview of on-going ESA PLC activities is provided and an outlook is given.

Detecting the single line to ground short circuit fault in the submarine’s power system using the artificial neural network

Directory of Open Access Journals (Sweden)

Behniafar Ali

2013-01-01

Full Text Available The electric marine instruments are newly inserted in the trade and industry, for which the existence of an equipped and reliable power system is necessitated. One of the features of such a power system is that it cannot have an earth system causing the protection relays not to be able to detect the single line to ground short circuit fault. While on the other hand, the occurrence of another similar fault at the same time can lead to the double line fault and thereby the tripping of relays and shortening of vital loads. This in turn endangers the personals' security and causes the loss of military plans. From the above considerations, it is inferred that detecting the single line to ground fault in the marine instruments is of a special importance. In this way, this paper intends to detect the single line to ground fault in the power systems of the marine instruments using the wavelet transform and Multi-Layer Perceptron (MLP neural network. In the numerical analysis, several different types of short circuit faults are simulated on several marine power systems and the proposed approach is applied to detect the single line to ground fault. The results are of a high quality and preciseness and perfectly demonstrate the effectiveness of the proposed approach.

Magnetic fields and cancer in people residing near Swedish high voltage power lines

Energy Technology Data Exchange (ETDEWEB)

Feychting, M; Ahlbom, A

1992-01-01

The study was designed as a case-control study, based on the population comprised of everyone who have lived on a property located within 300 meters from any of the 220 and 400 kV power lines in Sweden during the period from 1960 through 1985. For adults it was required that the duration of residence was at least one year. The corridor was chosen to be wide enough to ensure that it included both exposed and unexposed homes. The cases were all instances of cancer diagnosed between 1960-85. For children, all types of cancer were included, while for adults the study was restricted to leukemia and brain tumors. The controls were matched to the cases on time of diagnosis, age, sex, parish, and power line. Exposure was assessed in several different ways. First, spot measurements were performed in the homes of the subjects. Second, the magnetic fields generated by the power lines were calculated by means of a computer program taking distance, line configuration, and load into account. For childhood leukemia and with cut off points at 0.1 and 0.2 [mu]T, the relative risk (RR) increased over the two exposure levels and was estimated at 2.7 (95% c.l.: 1.0-6,3) for 0.2 [mu]T and over. The test for trend gave a p-value of 0.02. When the upper cut off point was shifted to 0.3 [mu]T the RR was instead 3.8 (1.4-9.3) and the corresponding trend test gave a p-value of 0.005. In adults and for magnetic fields of 0.2 [mu]T and over, the RR for acute myeloid (AML) and chronic myeloid leukemia (CML) were estimated at 1.7 (0.8-3.5) and 1.7 (0.7-3.8), respectively. This result persisted in most analyses. For brain tumours no association was seen. The results provide support for the hypothesis that exposure to magnetic fields increase the risk of cancer. This is most evident in childhood leukemia. What aspect of the fields that might be involved remains unclear. (6 figs., 82 tabs., 16 refs.).

Magnetic fields and cancer in people residing near Swedish high voltage power lines

Energy Technology Data Exchange (ETDEWEB)

Feychting, M; Ahlbom, A

1993-12-31

The study was designed as a case-control study, based on the population comprised of everyone who have lived on a property located within 300 meters from any of the 220 and 400 kV power lines in Sweden during the period from 1960 through 1985. For adults it was required that the duration of residence was at least one year. The corridor was chosen to be wide enough to ensure that it included both exposed and unexposed homes. The cases were all instances of cancer diagnosed between 1960-85. For children, all types of cancer were included, while for adults the study was restricted to leukemia and brain tumors. The controls were matched to the cases on time of diagnosis, age, sex, parish, and power line. Exposure was assessed in several different ways. First, spot measurements were performed in the homes of the subjects. Second, the magnetic fields generated by the power lines were calculated by means of a computer program taking distance, line configuration, and load into account. For childhood leukemia and with cut off points at 0.1 and 0.2 {mu}T, the relative risk (RR) increased over the two exposure levels and was estimated at 2.7 (95% c.l.: 1.0-6,3) for 0.2 {mu}T and over. The test for trend gave a p-value of 0.02. When the upper cut off point was shifted to 0.3 {mu}T the RR was instead 3.8 (1.4-9.3) and the corresponding trend test gave a p-value of 0.005. In adults and for magnetic fields of 0.2 {mu}T and over, the RR for acute myeloid (AML) and chronic myeloid leukemia (CML) were estimated at 1.7 (0.8-3.5) and 1.7 (0.7-3.8), respectively. This result persisted in most analyses. For brain tumours no association was seen. The results provide support for the hypothesis that exposure to magnetic fields increase the risk of cancer. This is most evident in childhood leukemia. What aspect of the fields that might be involved remains unclear. (6 figs., 82 tabs., 16 refs.).

Impact evaluation of conducted UWB transients on loads in power-line networks

Directory of Open Access Journals (Sweden)

B. Li

2017-09-01

Full Text Available Nowadays, faced with the ever-increasing dependence on diverse electronic devices and systems, the proliferation of potential electromagnetic interference (EMI becomes a critical threat for reliable operation. A typical issue is the electronics working reliably in power-line networks when exposed to electromagnetic environment. In this paper, we consider a conducted ultra-wideband (UWB disturbance, as an example of intentional electromagnetic interference (IEMI source, and perform the impact evaluation at the loads in a network. With the aid of fast Fourier transform (FFT, the UWB transient is characterized in the frequency domain. Based on a modified Baum–Liu–Tesche (BLT method, the EMI received at the loads, with complex impedance, is computed. Through inverse FFT (IFFT, we obtain time-domain responses of the loads. To evaluate the impact on loads, we employ five common, but important quantifiers, i.e., time-domain peak, total signal energy, peak signal power, peak time rate of change and peak time integral of the pulse. Moreover, to perform a comprehensive analysis, we also investigate the effects of the attributes (capacitive, resistive, or inductive of other loads connected to the network, the rise time and pulse width of the UWB transient, and the lengths of power lines. It is seen that, for the loads distributed in a network, the impact evaluation of IEMI should be based on the characteristics of the IEMI source, and the network features, such as load impedances, layout, and characteristics of cables.

Smart Grid Applications for a Practical Implementation of IP over Narrowband Power Line Communications

Directory of Open Access Journals (Sweden)

Noelia Uribe-Pérez

2017-11-01

Full Text Available Currently, Advanced Metering Infrastructure (AMI systems have equipped the low voltage section with a communication system that is being used mainly for metering purposes, but it can be further employed for additional applications related to the Smart Grid (SG concept. This paper explores the potential applications beyond metering of the available channel in a Power Line Communication-based AMI system. To that end, IP has been implemented over Narrow Band-Power Line Communication (NB-PLC in a real microgrid, which includes an AMI system. A thorough review of potential applications for the SG that might be implemented for this representative case is included in order to provide a realistic analysis of the potentiality of NB-PLC beyond smart metering. The results demonstrate that existing AMI systems based on NB-PLC have the capacity to implement additional applications such as remote commands or status signals, which entails an added value for deployed AMI systems.

Commissioning of the 28 GHz ECRH power transmission line for the TJ-II stellarator

Energy Technology Data Exchange (ETDEWEB)

Martínez-Fernández, J., E-mail: jose.martinez@ciemat.es [Laboratorio Nacional de Fusión (LNF), Centro de Investigaciones Tecnológicas, Medioambientales y Tecnológicas (CIEMAT), Av/Complutense 40, 28040 Madrid (Spain); Cappa, Á. [Laboratorio Nacional de Fusión (LNF), Centro de Investigaciones Tecnológicas, Medioambientales y Tecnológicas (CIEMAT), Av/Complutense 40, 28040 Madrid (Spain); Chirkov, A. [Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod (Russian Federation); Ros, A.; Tolkachev, A.; Catalán, G.; Soleto, A.; Redondo, M. [Laboratorio Nacional de Fusión (LNF), Centro de Investigaciones Tecnológicas, Medioambientales y Tecnológicas (CIEMAT), Av/Complutense 40, 28040 Madrid (Spain); Doane, J.L.; Anderson, J.P. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States)

2015-10-15

Highlights: • The 28 GHz power transmission line of the TJ-II stellarator is described. • Mismatch and alignment problems are covered, presenting infrared measurements. • Beam distortion in the matching optics unit led to unwanted modes in the waveguide. • After a redesign distortion was eliminated and coupling maximized. • Final measurements suggest finer alignment must be performed. - Abstract: The commissioning of the 28 GHz power transmission line of the TJ-II stellarator, designed for the excitation of electron Bernstein waves (EBW) through the O-X-B mode conversion process, is presented in this paper. Based upon a comprehensive set of thermal measurements, its purpose is to go into details about the several problems that arouse during the whole process, namely higher order modes excitation because of the wider beam size and alignment mismatches at the waveguide mouth. All these drawbacks may have prevented the correct O-X mode conversion, thus providing a reasonable explanation for the unsuccessful EBW heating experiments.

Cryogenic Fiber Optic Sensors for Superconducting Magnets and Power Transmission Lines in High Energy Physics Applications

CERN Document Server

AUTHOR|(CDS)2081689; Bajko, Marta

In the framework of the Luminosity upgrade of the Large Hadron Collider (HL - LHC), a remarkable R&D effort is now ongoing at the European Organization for Nuclear Research (CERN) in order to develop a new generation of accelerator magnets and superconducting power transmission lines. The magnet technology will be based on Nb$_{3}$Sn enabling to operate in the 11 - 13 T range. In parallel, in order to preserve the power converters from the increasing radiation level, high power transmission lines are foreseen to feed the magnets from free - radiation zones. These will be based on high temperature superconductors cooled down with helium gas in the range 5 - 30 K. The new technologies will require advanced design and fabrication approaches as well as adapted instrumentation for monitoring both the R&D phase and operation. Resistive sensors have been used so far for voltage, temperature and strain monitoring but their integration still suffers from the number of electrical wires and the complex compensat...

Transmission-line-circuit model of an 85-TW, 25-MA pulsed-power accelerator

Science.gov (United States)

Hutsel, B. T.; Corcoran, P. A.; Cuneo, M. E.; Gomez, M. R.; Hess, M. H.; Hinshelwood, D. D.; Jennings, C. A.; Laity, G. R.; Lamppa, D. C.; McBride, R. D.; Moore, J. K.; Myers, A.; Rose, D. V.; Slutz, S. A.; Stygar, W. A.; Waisman, E. M.; Welch, D. R.; Whitney, B. A.

2018-03-01

We have developed a physics-based transmission-line-circuit model of the Z pulsed-power accelerator. The 33-m-diameter Z machine generates a peak electrical power as high as 85 TW, and delivers as much as 25 MA to a physics load. The circuit model is used to design and analyze experiments conducted on Z. The model consists of 36 networks of transmission-line-circuit elements and resistors that represent each of Zs 36 modules. The model of each module includes a Marx generator, intermediate-energy-storage capacitor, laser-triggered gas switch, pulse-forming line, self-break water switches, and tri-plate transmission lines. The circuit model also includes elements that represent Zs water convolute, vacuum insulator stack, four parallel outer magnetically insulated vacuum transmission lines (MITLs), double-post-hole vacuum convolute, inner vacuum MITL, and physics load. Within the vacuum-transmission-line system the model conducts analytic calculations of current loss. To calculate the loss, the model simulates the following processes: (i) electron emission from MITL cathode surfaces wherever an electric-field threshold has been exceeded; (ii) electron loss in the MITLs before magnetic insulation has been established; (iii) flow of electrons emitted by the outer-MITL cathodes after insulation has been established; (iv) closure of MITL anode-cathode (AK) gaps due to expansion of cathode plasma; (v) energy loss to MITL conductors operated at high lineal current densities; (vi) heating of MITL-anode surfaces due to conduction current and deposition of electron kinetic energy; (vii) negative-space-charge-enhanced ion emission from MITL anode surfaces wherever an anode-surface-temperature threshold has been exceeded; and (viii) closure of MITL AK gaps due to expansion of anode plasma. The circuit model is expected to be most accurate when the fractional current loss is small. We have performed circuit simulations of 52 Z experiments conducted with a variety of accelerator

Transmission-line-circuit model of an 85-TW, 25-MA pulsed-power accelerator

Directory of Open Access Journals (Sweden)

B. T. Hutsel

2018-03-01

Full Text Available We have developed a physics-based transmission-line-circuit model of the Z pulsed-power accelerator. The 33-m-diameter Z machine generates a peak electrical power as high as 85 TW, and delivers as much as 25 MA to a physics load. The circuit model is used to design and analyze experiments conducted on Z. The model consists of 36 networks of transmission-line-circuit elements and resistors that represent each of Zs 36 modules. The model of each module includes a Marx generator, intermediate-energy-storage capacitor, laser-triggered gas switch, pulse-forming line, self-break water switches, and tri-plate transmission lines. The circuit model also includes elements that represent Zs water convolute, vacuum insulator stack, four parallel outer magnetically insulated vacuum transmission lines (MITLs, double-post-hole vacuum convolute, inner vacuum MITL, and physics load. Within the vacuum-transmission-line system the model conducts analytic calculations of current loss. To calculate the loss, the model simulates the following processes: (i electron emission from MITL cathode surfaces wherever an electric-field threshold has been exceeded; (ii electron loss in the MITLs before magnetic insulation has been established; (iii flow of electrons emitted by the outer-MITL cathodes after insulation has been established; (iv closure of MITL anode-cathode (AK gaps due to expansion of cathode plasma; (v energy loss to MITL conductors operated at high lineal current densities; (vi heating of MITL-anode surfaces due to conduction current and deposition of electron kinetic energy; (vii negative-space-charge-enhanced ion emission from MITL anode surfaces wherever an anode-surface-temperature threshold has been exceeded; and (viii closure of MITL AK gaps due to expansion of anode plasma. The circuit model is expected to be most accurate when the fractional current loss is small. We have performed circuit simulations of 52 Z experiments conducted with a

Power system EMP protection. Final report

International Nuclear Information System (INIS)

Marable, J.H.; Barnes, P.R.; Nelson, D.B.

1975-05-01

Voltage transients induced in electric power lines and control circuits by the electromagnetic pulse (EMP) from high-altitude nuclear detonations may cause widespread power failure and damage in electric power systems. This report contains a parametric study of EMP power line surges and discusses protective measures to minimize their effects. Since EMP surges have considerably greater rates of rise than lightning surges, recommended standards and test procedures are given to assure that surge arresters protect equipment from damage by EMP. Expected disturbances and damage to power systems are reviewed, and actions are presented which distribution companies can take to counter them. These include backup communications methods, stockpiling of vulnerable parts, repair procedures, and dispatcher actions to prevent blackout from EMP-caused instabilities. A long-range program is presented for improving distributors' protection against EMP. This involves employee training, hardware protection for power and control circuits, and improvement of plans for emergency action. (U.S.)

Functional consequences of structural differences in stingray sensory systems. Part I: mechanosensory lateral line canals.

Science.gov (United States)

Jordan, Laura K; Kajiura, Stephen M; Gordon, Malcolm S

2009-10-01

Short range hydrodynamic and electrosensory signals are important during final stages of prey capture in elasmobranchs (sharks, skates and rays), and may be particularly useful for dorso-ventrally flattened batoids with mouths hidden from their eyes. In stingrays, both the lateral line canal and electrosensory systems are highly modified and complex with significant differences on ventral surfaces that relate to feeding ecology. This study tests functional hypotheses based on quantified differences in sensory system morphology of three stingray species, Urobatis halleri, Myliobatis californica and Pteroplatytrygon violacea. Part I investigates the mechanosensory lateral line canal system whereas part II focuses on the electrosensory system. Stingray lateral line canals include both pored and non-pored sections and differ in branching complexity and distribution. A greater proportion of pored canals and high pore numbers were predicted to correspond to increased response to water flow. Behavioral experiments were performed to compare responses of stingrays to weak water jets mimicking signals produced by potential prey at velocities of 10-20 cm s(-1). Bat rays, M. californica, have the most complex and broadly distributed pored canal network and demonstrated both the highest response rate and greater response intensity to water jet signals. Results suggest that U. halleri and P. violacea may rely on additional sensory input, including tactile and visual cues, respectively, to initiate stronger feeding responses. These results suggest that stingray lateral line canal morphology can indicate detection capabilities through responsiveness to weak water jets.

Optimized transmission-line impedance transformers for petawatt-class pulsed-power accelerators

Directory of Open Access Journals (Sweden)

D. R. Welch

2008-03-01

Full Text Available We have developed 1D analytic and 2D fully electromagnetic models of radial transmission-line impedance transformers. The models have been used to quantify the power-transport efficiency and pulse sharpening of such transformers as a function of voltage pulse width and impedance profile. For the cases considered, we find that in the limit as Γ→0 (where Γ is the ratio of the pulse width to the one-way transit time of the transformer, the transport efficiency is maximized when the impedance profile is exponential. As Γ increases from zero, the optimum profile gradually deviates from an exponential. A numerical procedure is presented that determines the optimum profile for a given pulse shape and width. The procedure can be applied to optimize the design of impedance transformers used in petawatt-class pulsed-power accelerators.

Radiating nonuniform transmission-line systems and the partial element equivalent circuit method

CERN Document Server

Nitsch, Juergen; Wollenberg, Gunter

2009-01-01

High frequencies of densely packed modern electronic equipment turn even the smallest piece of wire into a transmission line with signal retardation, dispersion, attenuation, and distortion. In electromagnetic environments with high-power microwave or ultra-wideband sources, transmission lines pick up noise currents generated by external electromagnetic fields. These are superimposed on essential signals, the lines acting not only as receiving antennas but radiating parts of the signal energy into the environment. This book is outstanding in its originality. While many textbooks rephrase

Demand management through centralized control system using power line communication for existing buildings

International Nuclear Information System (INIS)

Al-Mulla, A.; ElSherbini, A.

2014-01-01

Highlights: • A pilot system was developed for demand management of equipment in buildings. • The networking was based on LonWorks platform and power line communication. • Demand strategies led to load reductions up to 74% and energy savings up to 25%. • The peak load reduction is expected to reach 3.44 GW by the year 2030. - Abstract: Managing peak demand efficiently is vital for maintaining uninterrupted supply of electrical power by utility providers. In this work, a pilot system was developed for managing and controlling the demand of major power consuming equipment in buildings from a central server, while relying mostly on existing infrastructure and maintaining consumer comfort. The system was successfully demonstrated on a selected group of buildings using the LonWorks networking platform. At the building level, the system utilized power line and twisted pair communication to control the thermostats of air-conditioning (A/C) units. The higher level communication was executed through extensible markup language (XML) and simple object access protocol (SOAP). The system provided control capabilities based on A/C unit priority, thermostat temperature, building type and geographic location. The development and execution of demand management strategies for selected buildings led to peak load reductions up to 74%, in addition to energy savings up to 25%. Implementing such a system at a national level in Kuwait is estimated to reduce peak demand by 3.44 GW, amounting to capital savings of $4.13 billion. The use of existing infrastructure reduced the cost and installation time of the system. Based on the successful testing of this pilot system, a larger-scale system is being developed

Frequency domain based LS channel estimation in OFDM based Power line communications

OpenAIRE

Bogdanović, Mario

2015-01-01

This paper is focused on low voltage power line communication (PLC) realization with an emphasis on channel estimation techniques. The Orthogonal Frequency Division Multiplexing (OFDM) scheme is preferred technology in PLC systems because of its effective combat with frequency selective fading properties of PLC channel. As the channel estimation is one of the crucial problems in OFDM based PLC system because of a problematic area of PLC signal attenuation and interference, the improved LS est...

Study of data transmission over drive motor power cables of a remotely operated robot using power line communication technology

International Nuclear Information System (INIS)

Balaji, Kanchi; Singh, Ashutosh Pratap; Rakesh, V.; Rajagopalan, C.; Murugan, S.

2016-01-01

In nuclear power plants (NPPs), robotic devices are widely used for carrying out in-service inspection (lSI) and repair tasks at elevated temperatures and radiation environments. These devices comprises servo motors that are powered and controlled by the motion control unit/electric drives. The control and inspection data are to be transmitted back from the inspection device to the control unit using separate industrial graded data transmission cables compatible for high temperature applications. This increases complexity of robot trailing cables and cost. Hence, it is proposed to use power cables that are used for powering the motor for sending information signals using power line communication (PLC) technology. The domestically used PLC modems adds noise to the information signal when coupled on to the motor feed cables during IGBT switching. Therefore, passive low pass filters are used at the motor drive end to reduce the impulsive noise. The aim of this study is to compare noise characteristics for different type of filter structures over pulse width modulation (PWM) network. We will highlight the choice of cut off frequency of filter based on frequency of information signal

Removal of power line interference of space bearing vibration signal based on the morphological filter and blind source separation

Science.gov (United States)

Dong, Shaojiang; Sun, Dihua; Xu, Xiangyang; Tang, Baoping

2017-06-01

Aiming at the problem that it is difficult to extract the feature information from the space bearing vibration signal because of different noise, for example the running trend information, high-frequency noise and especially the existence of lot of power line interference (50Hz) and its octave ingredients of the running space simulated equipment in the ground. This article proposed a combination method to eliminate them. Firstly, the EMD is used to remove the running trend item information of the signal, the running trend that affect the signal processing accuracy is eliminated. Then the morphological filter is used to eliminate high-frequency noise. Finally, the components and characteristics of the power line interference are researched, based on the characteristics of the interference, the revised blind source separation model is used to remove the power line interferences. Through analysis of simulation and practical application, results suggest that the proposed method can effectively eliminate those noise.

Using technique vibration diagnostics for assessing the quality of power transmission line supports repairs

Directory of Open Access Journals (Sweden)

Cherpakov Aleksander

2017-01-01

Full Text Available The considered method for assessing the quality of the repair work to restore the rack supports of transmission lines is based on the method of vibration diagnostics. Power transmission line supports with a symmetrical destruction of the protective layer of concrete in the ground in violation of the construction section were chosen as an object. Finite element modelling package Ansys was used in assessing the quality of repair work. The example of evaluating the quality of repair using the relative adhesion defective area design criteria in the analysis of natural vibration frequencies is given.

Geographic information system(GIS) applications to optimize route selection, environmental analysis and power transmission line designs; Aplicaciones en sistemas de informacion geograficos (SIG) para optimizar seleccion de ruta, analisis ambiental y diseno de lineas de transmision

Energy Technology Data Exchange (ETDEWEB)

Cadena Suarez, Luis Fernando; Posada Delgado, Fabio Humberto; Alvarez Davila, Esteban; Gomez Colorado, Oscar Alberto [Interconexion Electrica S.A. (ISA), Medellin (Colombia)]. E-mail: fecadena@isa.com.co

2001-07-01

Interconexion Eletrica s.a. (ISA) is a company of the Colombian government for electric energy transportation through the national energy transportation network, it makes part of the companies group with growing environmental conscience. The better route identifications for high voltage transmission lines do not involve just the engineering analyses, but mainly the environmental one.These integrated analysis have been largely powered through the technology applications like Geographic Information Systems (GIS) and Remote Sensing (RS). These technologies were applied for a total of 300 kilometers between 1992 and 2000 in the largest power transmission lines whose configurations cross different geographic conditions. This current technical contribution describes the application of GIS and RS technologies for the best routes, environmental sensibility analysis and environmental impact evaluations. The applications have resulted in the integration between engineering and environmental processes, optimization of environmental evaluation, formulations of procedures handling and environmental control, as well as transmission line profile characteristics. After the project construction, GIS can be used as a useful tool for environmental monitoring in connection with power transmission lines, maintenance of servitude areas, availability conditions and quality of the high voltage transmission service.

Impact mortality of black storks (Ciconia nigra) on medium-voltage overhead power lines in Rheinland-Pfalz; Anflugverluste von Schwarzstoerchen (Ciconia nigra) an Mittelspannungsfreileitungen in Rheinland-Pfalz

Energy Technology Data Exchange (ETDEWEB)

Hormann, M.; Richarz, K. [Staatliche Vogelschutzwarte fuer Hessen, Rheinland-Pfalz und Saarland, Frankfurt am Main (Germany)

1997-12-01

The small breeding population of black storks (Ciconia nigra), which had been growing steadily since first nesting in Rhineland-Palantinate in 1982, has been observably decreasing again since 1993, particularly in its main territories. The high mortality of, for the most part, juvenile black storks resulting from collision with a overhead power line (OHL) is described (30 collision victims since the mid-1980s). The energy utilities are called upon to install underground cables on the relevant sections of the power lines in addition to modifying hazardous types of towers in order to reduce the high bird mortality rate. (orig.) [Deutsch] Fuer den seit einer Erstbrut 1982 in Rheinland-Pfalz stetig angestiegenen kleinen Brutbestand des Schwarzstorchs (Ciconia nigra) sind vor allem in seinen Kerngebieten seit 1993 wieder Bestandsrueckgaenge zu verzeichnen. Die hohen Verluste ueberwiegend junger Schwarzstoerche durch Anflug an Mittel- und Niederspannungsfreileitungen (seit Mitte der 80er Jahre 30 Schwarzstoerche als Anflugopfer) werden beschrieben. Neben der Entschaerfung gefaehrlicher Masttypen wird zur Vermeidung der hohen Anflugverluste eine Erdverkabelung der kritischen Leitungsabschnitte gefordert. (orig.)

Soft power as part of China's strategy for national image cultivation

DEFF Research Database (Denmark)

Overgaard, Signe

In recent years soft power has become a key issue at the highest political level in China, focusing especially on cultural soft power. This is reflected in important political documents, such as five year plans, plenum meeting summaries, as well as speeches by Hu Jintao and other politicians...... at the highest level. This interest in soft power is generally seen as part of an important foreign policy shift, and the huge amounts of money spent by the government on cultural diplomacy testify to the importance attached to it. Understanding what might be the goal of China’s soft power strategy is however...... difficult. The question can be analysed from various perspectives focusing on the use of power, the peaceful development discourse, or national image cultivation, and finding a straight forward answer is therefore difficult. If we go deeper and see the soft power discourse in the context of the worries...

Audio-frequency noise emissions from high-voltage overhead power lines

International Nuclear Information System (INIS)

Semmler, M.; Straumann, U.; Roero, C.; Teich, T. H.

2005-01-01

This article discusses the noise-emissions caused by high-voltage overhead power lines that can occur under certain atmospheric conditions. These emissions, caused by electric discharges around the conductors, can achieve disturbing values, depending on the conditions prevailing at the time in question. The causes of the discharges are examined and the ionisation processes involved are looked at. The parameters influencing the discharges are discussed and measures that can be taken to reduce such audio-frequency emissions are looked at. The authors note that a reduction of peripheral field strengths can reduce emissions and that hydrophilic coatings can lead to faster reduction of such effects after rainfall

Civilian Power Program. Part 1, Summary, Current status of reactor concepts

Energy Technology Data Exchange (ETDEWEB)

Author, Not Given

1959-09-01

This study group covered the following: delineation of the specific objectives of the overall US AEC civilian power reactor program, technical objectives of each reactor concept, preparation of a chronological development program for each reactor concept, evaluation of the economic potential of each reactor type, a program to encourage the the development, and yardsticks for measuring the development. Results were used for policy review by AEC, program direction, authorization and appropriation requests, etc. This evaluation encompassed civilian power reactors rated at 25 MW(e) or larger and related experimental facilities and R&D. This Part I summarizes the significant results of the comprehensive effort to determine the current technical and economic status for each reactor concept; it is based on the 8 individual technical status reports (Part III).

A Design of a 345-kV Electric Power Transmission Line Interlinking Ramu and Rouna Grids in Papua New Guinea

Directory of Open Access Journals (Sweden)

Sakato Francis

2017-01-01

Full Text Available According to PNG Power Limited (PPL, Papua New Guinea’s peak power demand is expected to increase from 210 MW in 2012 to 347 MW in 2026. Under the current state of the power sector in Papua New Guinea (PNG, it is critical to implement measures to cope with the increasing power demand to promote investment, economic growth, and ultimately to achieve poverty reduction through economic growth. One of the solutions identified to improve the reliability of PNG power systems and thus to meet the demand is to interconnect the major grids in the country so that the loads could be shared among them. This project embarks in designing a 345-kV electric power transmission line to interlink the Ramu and Rouna power grids of Papua New Guinea. The design is done by analysing all the necessary aspects of the transmission lines with in-depth calculations performed using MATHCAD software. This design is the basis for extra-high voltage (EHV transmission network in anticipation for the power generation and demand growth in PNG.

On-line alkali monitoring - Part 1; Kontinuerlig alkalimaetning - Etapp 1

Energy Technology Data Exchange (ETDEWEB)

Andersson, Christer; Ljung, P; Woxlin, H

1997-02-01

As a consequence of the increased knowledge of the environmental impact of combustion based heat and power generation, the use of renewable biofuels will be increased. An obstacle associated to biofuel combustion compared to other fuels is the large release of alkali. Alkali compounds in flue gases are known to cause severe operational problems. Three of the major problems are; fouling of superheating tubes (causing reduced heat transfer and possibly corrosion), agglomeration of the bed material in fluidized beds, and poisoning of SCR catalysts. Yet another alkali related problem arises when, in order to increase the electric efficiency of combustion power plants, combined-cycle technology is used. Alkali vapour present in the fuel gas for the gas turbine is condensed to particles which increase corrosion and erosion of the turbine blades. The research on ash related operational problems has to be extended in order to ensure future use of biofuels in heat and power generation. In all successful research, adequate tools are necessary. To investigate ash related problems the key issue is to be able to perform continuous alkali measurements. This pilot study has investigated the need of continuous alkali measurements, which alkali species are harmful in the different applications and also available instrumentation capable of measuring the specific alkali species. The report gives a short summary presenting alkali related operational problems. In addition a schematic overview is given, showing the alkali species that possibly can exist in various parts of the power plant. 48 refs, 13 figs, 4 tabs

10 CFR Appendix S to Part 50 - Earthquake Engineering Criteria for Nuclear Power Plants

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Earthquake Engineering Criteria for Nuclear Power Plants S... FACILITIES Pt. 50, App. S Appendix S to Part 50—Earthquake Engineering Criteria for Nuclear Power Plants... nuclear power plant structures, systems, and components important to safety to withstand the effects of...

Solving Man-Induced Large-Scale Conservation Problems: The Spanish Imperial Eagle and Power Lines

Science.gov (United States)

López-López, Pascual; Ferrer, Miguel; Madero, Agustín; Casado, Eva; McGrady, Michael

2011-01-01

Background Man-induced mortality of birds caused by electrocution with poorly-designed pylons and power lines has been reported to be an important mortality factor that could become a major cause of population decline of one of the world rarest raptors, the Spanish imperial eagle (Aquila adalberti). Consequently it has resulted in an increasing awareness of this problem amongst land managers and the public at large, as well as increased research into the distribution of electrocution events and likely mitigation measures. Methodology/Principal Findings We provide information of how mitigation measures implemented on a regional level under the conservation program of the Spanish imperial eagle have resulted in a positive shift of demographic trends in Spain. A 35 years temporal data set (1974–2009) on mortality of Spanish imperial eagle was recorded, including population censuses, and data on electrocution and non-electrocution of birds. Additional information was obtained from 32 radio-tracked young eagles and specific field surveys. Data were divided into two periods, before and after the approval of a regional regulation of power line design in 1990 which established mandatory rules aimed at minimizing or eliminating the negative impacts of power lines facilities on avian populations. Our results show how population size and the average annual percentage of population change have increased between the two periods, whereas the number of electrocuted birds has been reduced in spite of the continuous growing of the wiring network. Conclusions Our results demonstrate that solving bird electrocution is an affordable problem if political interest is shown and financial investment is made. The combination of an adequate spatial planning with a sustainable development of human infrastructures will contribute positively to the conservation of the Spanish imperial eagle and may underpin population growth and range expansion, with positive side effects on other endangered

Stray current induced corrosion in lightning rod cables of 525 kV power lines towers: a case study

International Nuclear Information System (INIS)

Wojcicki, F. R.; Negrisoli, M. E. M.; Franco, C. V.

2003-01-01

With the growth of several areas in modern society, the necessity to generate and carry electrical energy to big cities has greatly increased. Cables supported by power towers with galvanized steel foundation usually carry energy. As the foundations are underground they may cause high rates of corrosion. These are usually detected by a conventional potential measurement using a Cu/CuSO 4 reference electrode. It is believed that corrosion results from stray currents that flow through the ground to close the loop between neighboring towers. Stray currents originate in the lightning rod cables of the power line towers, induced by the strong electromagnetic and electric fields of the energized power lines. The intensity and direction of those currents were measured, indicating substantial values of both their AC and DC components. The potential of the tower ground system, measured in the perpendicular direction of the main axis of the power line, was plotted as a function of the distance to the tower base. The results clearly indicated the tendency to corrosive attack in the anodic towers as reflected by the slope of the plot, whereas no signs of corrosion could be found in the reverse slope, confirming the visual inspection of the foundation. The profile of the potential plots could be changed providing the electric insulation of the lightning rod cable. (Author) 8 refs

Accurate fault location algorithm on power transmission lines with use of two-end unsynchronized measurements

Directory of Open Access Journals (Sweden)

Mohamed Dine

2012-01-01

Full Text Available This paper presents a new approach to fault location on power transmission lines. This approach uses two-end unsynchronised measurements of the line and benefits from the advantages of digital technology and numerical relaying, which are available today and can easily be applied for off-line analysis. The approach is to modify the apparent impedance method using a very simple first-order formula. The new method is independent of fault resistance, source impedances and pre-fault currents. In addition, the data volume communicated between relays is sufficiently small enough to be transmitted easily using a digital protection channel. The proposed approach is tested via digital simulation using MATLand the applied test results corroborate the superior performance of the proposed approach.

Heavy density concrete for nuclear radiation shielding and power stations: [Part]2

International Nuclear Information System (INIS)

Singha Roy, P.K.

1987-01-01

This article is the second part of the paper entitled 'Heavy density concrete for nuclear radiation shielding and power stations'. In this part, some of the important properties of heavy density concrete are discussed. They include density, water retentivity, air content, permeability with special reference to concrete mixes used in India's nuclear power reactors. All these properties are affected to various extents by heating. Indian shield concrete is rarely subjected to temperatures above 60degC during its life, because of thermal shield protection. During placement, the maximum anticipated rise in temperature due to heat of hydration is restricted to around 45degC by chilling, if necessary to reduce shrinkage stresses and cracks. (M.G.B.)

32 CFR Appendix F to Part 623 - Power of Attorney (DA Form 4881-4-R)

Science.gov (United States)

2010-07-01

... 32 National Defense 3 2010-07-01 2010-07-01 true Power of Attorney (DA Form 4881-4-R) F Appendix F to Part 623 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY SUPPLIES AND EQUIPMENT LOAN OF ARMY MATERIEL Pt. 623, App. F Appendix F to Part 623—Power of Attorney (DA Form 4881-4-R...

Wet snow hazard for power lines: a forecast and alert system applied in Italy

Directory of Open Access Journals (Sweden)

P. Bonelli

2011-09-01

Full Text Available Wet snow icing accretion on power lines is a real problem in Italy, causing failures on high and medium voltage power supplies during the cold season. The phenomenon is a process in which many large and local scale variables contribute in a complex way and not completely understood. A numerical weather forecast can be used to select areas where wet snow accretion has an high probability of occurring, but a specific accretion model must also be used to estimate the load of an ice sleeve and its hazard. All the information must be carefully selected and shown to the electric grid operator in order to warn him promptly.

The authors describe a prototype of forecast and alert system, WOLF (Wet snow Overload aLert and Forecast, developed and applied in Italy. The prototype elaborates the output of a numerical weather prediction model, as temperature, precipitation, wind intensity and direction, to determine the areas of potential risk for the power lines. Then an accretion model computes the ice sleeves' load for different conductor diameters. The highest values are selected and displayed on a WEB-GIS application principally devoted to the electric operator, but also to more expert users. Some experimental field campaigns have been conducted to better parameterize the accretion model. Comparisons between real accidents and forecasted icing conditions are presented and discussed.

Wet snow hazard for power lines: a forecast and alert system applied in Italy

Science.gov (United States)

Bonelli, P.; Lacavalla, M.; Marcacci, P.; Mariani, G.; Stella, G.

2011-09-01

Wet snow icing accretion on power lines is a real problem in Italy, causing failures on high and medium voltage power supplies during the cold season. The phenomenon is a process in which many large and local scale variables contribute in a complex way and not completely understood. A numerical weather forecast can be used to select areas where wet snow accretion has an high probability of occurring, but a specific accretion model must also be used to estimate the load of an ice sleeve and its hazard. All the information must be carefully selected and shown to the electric grid operator in order to warn him promptly. The authors describe a prototype of forecast and alert system, WOLF (Wet snow Overload aLert and Forecast), developed and applied in Italy. The prototype elaborates the output of a numerical weather prediction model, as temperature, precipitation, wind intensity and direction, to determine the areas of potential risk for the power lines. Then an accretion model computes the ice sleeves' load for different conductor diameters. The highest values are selected and displayed on a WEB-GIS application principally devoted to the electric operator, but also to more expert users. Some experimental field campaigns have been conducted to better parameterize the accretion model. Comparisons between real accidents and forecasted icing conditions are presented and discussed.

Construction and assembling optimization of power equipment

Directory of Open Access Journals (Sweden)

Marius Groza

2005-10-01

Full Text Available The main purpose of this paper is to elaborate a calculation program in Pascal language, using Delphi environment. This calculation program is designed to solve the power engineering optimization problems using the critical path method. For illustrating the use of the algorithm and the calculation program we propose an application from power engineering: a 400 kV electrical overhead line section realization. This paper is structured in 4 parts. In the first part of the paper we present the application as a problem of critic path. In the second part of the paper, we determine the critic path in a program graph and time reserves. In the third part of the paper we present a representative numerical application. In the fourth part of the paper it is described the calculation program.

Social class, political power, and the state: their implications in medicine--parts I and II.

Science.gov (United States)

Navarro, V

1976-01-01

This three part article presents an anlysis of the distribution of power and of the nature of the state in Western industrialized societies and details their implications in medicine. Part I presents a critique of contemporary theories of the Western system of power; discusses the countervailing pluralist and power elite theories, as well as those of bureaucratic and professional control; and concludes with an examination of the Marxist theories of economic determinism, structural determinism, and corporate statism. Part II presents a Marxist theory of the role, nature, and characteristics of state intervention. Part III (which will appear in the next issue of this journal) focuses on the mode of that intervention and the reasons for its growth, with an added analysis of the attributes of state intervention in the health sector, and of the dialectical relationship between its growth and the current fiscal crisis of the state. In all three parts, the focus is on Western European countries and on North America, with many examples and categories from the area of medicine.

Termination for a superconducting power transmission line including a horizontal cryogenic bushing

Science.gov (United States)

Minati, Kurt F.; Morgan, Gerry H.; McNerney, Andrew J.; Schauer, Felix

1984-01-01

A termination for a superconducting power transmission line is disclosed which is comprised of a standard air entrance insulated vertical bushing with an elbow, a horizontal cryogenic bushing linking the pressurized cryogenic cable environment to the ambient temperature bushing and a stress cone which terminates the cable outer shield and transforms the large radial voltage gradient in the cable dielectric into a much lower radial voltage gradient in the high density helium coolant at the cold end of the cryogenic bushing.

SYNTHESIS OF ACTIVE SCREENING SYSTEM OF MAGNETIC FIELD OF HIGH VOLTAGE POWER LINES OF DIFFERENT DESIGN TAKING INTO ACCOUNT SPATIAL AND TEMPORAL DISTRIBUTION OF MAGNETIC FIELD

Directory of Open Access Journals (Sweden)

B.I. Kuznetsov

2017-04-01

Full Text Available Purpose. Analyze the spatial and temporal distribution of the magnetic field of high voltage power lines with different design allowing and development of recommendations for the design of active screening systems by magnetic field of high voltage power lines. Methodology. Analysis of the spatial and temporal distribution of the magnetic field of high voltage power lines of different design allowing is made on the basis of Maxwell's equations solutions in the quasi-stationary approximation. Determination of the number, configuration, spatial arrangement and the compensation coil currents is formulated in the form of multiobjective optimization problem that is solved by multi-agent multiswarm stochastic optimization based on Pareto optimal solutions. Results of active screening system for the synthesis of various types of transmission lines with different numbers of windings controlled. The possibility of a significant reduction in the level of the flux density of the magnetic field source within a given region of space. Originality. For the first time an analysis of the spatial and temporal distribution of the magnetic field of power lines with different types and based on findings developed recommendations for the design of active screening system by magnetic field of high voltage power lines. Practical value. Practical recommendations on reasonable choice of the number and spatial arrangement of compensating windings of active screening system by magnetic field of high voltage power lines of different design allowing for the spatial and temporal distribution of the magnetic field. Results of active screening system synthesis of the magnetic field of industrial frequency generated by single-circuit 110 kV high voltage power lines with the supports have 330 - 1T «triangle» rotating magnetic field with full polarization in a residential five-storey building, located near the power lines. The system contains three compensating coil and reduces

Qinshan phase II extension nuclear power project thermal stratification and fatigue stress analysis for pressurizer surge line

International Nuclear Information System (INIS)

Yu Xiaofei; Zhang Yixiong; Ai Honglei

2010-01-01

Thermal stratification of pressurizer surge line induced by the inside fluid brings on global bending moments, local thermal stresses, unexpected displacements and support loadings of the pipe system. In order to avoid a costly three-dimensional computation, a combined 1D/2D technique has been developed and implemented to analyze the thermal stratification and fatigue stress of pressurize surge line of QINSHAN Phase II Extension Nuclear Power Project in this paper, using the computer codes SYSTUS and ROCOCO. According to the mechanical analysis results of stratification, the maximum stress and cumulative usage factor, the loadings at connections of surge line to main pipe and RCP and the displacements of surge line at supports are obtained. (authors)

An adaptive observer for on-line tool wear estimation in turning, Part I: Theory

Science.gov (United States)

Danai, Kourosh; Ulsoy, A. Galip

1987-04-01

On-line sensing of tool wear has been a long-standing goal of the manufacturing engineering community. In the absence of any reliable on-line tool wear sensors, a new model-based approach for tool wear estimation has been proposed. This approach is an adaptive observer, based on force measurement, which uses both parameter and state estimation techniques. The design of the adaptive observer is based upon a dynamic state model of tool wear in turning. This paper (Part I) presents the model, and explains its use as the basis for the adaptive observer design. This model uses flank wear and crater wear as state variables, feed as the input, and the cutting force as the output. The suitability of the model as the basis for adaptive observation is also verified. The implementation of the adaptive observer requires the design of a state observer and a parameter estimator. To obtain the model parameters for tuning the adaptive observer procedures for linearisation of the non-linear model are specified. The implementation of the adaptive observer in turning and experimental results are presented in a companion paper (Part II).

Direct HST Dust Lane Detection in Powerful Narrow-Line Radio Galaxies

Energy Technology Data Exchange (ETDEWEB)

Ramírez, Edgar A.; Aretxaga, Itziar [Instituto Nacional de Astrofísica, Óptica y Electrónica, Puebla (Mexico); Tadhunter, Clive N. [Department of Physics and Astronomy, University of Sheffield, Sheffield (United Kingdom); Lopez-Rodriguez, Enrique [NASA Ames Research Center, SOFIA Science Center, SOFIA/USRA, Mountain View, CA (United States); Department of Astronomy, University of Texas at Austin, Austin, TX (United States); McDonald Observatory, University of Texas at Austin, Austin, TX (United States); Packham, Chris, E-mail: e.ramirez@inaoep.mx [Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX (United States); National Astronomical Observatory of Japan, Tokyo (Japan)

2017-11-22

We present the analysis of near-infrared Hubble Space Telescope imaging of 10 Fanaroff Riley II powerful radio galaxies at low redshift (0.03 < z < 0.11) optically classified as narrow-line radio galaxies. The photometric properties of the host galaxy are measured using galfit, and compared with those from the literature. Our high resolution near-infrared observations provide new and direct information on the central kpc-scale dust lanes in our sample that could be connected to the pc-scale torus structure. Moreover, analyzing the infrared spectrograph Spitzer spectra of our sample, we suggest properties of the dust size of the torus.

Calculation of radioactive inventory of activated parts for nuclear power unit and analysis of influence factors

International Nuclear Information System (INIS)

Liu Yang; Cai Qi; Lin Xiaoling

2011-01-01

Based on the operation characteristics of the nuclear power unit, the radioactive inventory of activated parts was calculated by ORIGEN2, and the effects of bum-up, operation mode and power change on the radioactive inventory for activated parts were analyzed. The results indicated that the radioactive inventory grew with the increasing of burn-up, and when the actual operation time was longer than the effective operation time, the increasing rate of nuclide activity approximated the burn-up increasing; Radioactive inventory of activated parts was influenced directly by the operation modes of the nuclear power unit, and under same reactor load, operation power and bum-up, the radioactive inventory for non-continuous operation mode is less than that for the continuous operation mode. Effects of operation modes on radioactive inventory reversed with half life of nuclides. Under same bum-up and longer operation time, the effect of operation power change on the radioactive inventory is not obvious, (authors)

Protection Coordination in Electrical Substation Part-2 Unit Protections (Differential and Distance Protection)

OpenAIRE

TÜR, Mehmet Rida; Shobole, Abdulfetah; Baysal, Mustafa; Wadi, Mohammed

2018-01-01

Power systemsmust be protected against faults to ensure quality and reliable generation,transmission and distribution of power systems. Power system protection is providedby the protection relays. This paper is the second part of the ProtectionCoordination study for the Siddik Kardesler Substation. The protection fortransmission lines, transformer, bus bars and customer feeders is provided byovercurrent protection, differential and distance protection schemes. In thispaper, issues related wit...

Nuclear techniques for the on-line bulk analysis of carbon in coal-fired power stations.

Science.gov (United States)

Sowerby, B D

2009-09-01

Carbon trading schemes usually require large emitters of CO(2), such as coal-fired power stations, to monitor, report and be audited on their CO(2) emissions. The emission price provides a significant additional incentive for power stations to improve efficiency. In the present paper, previous work on the bulk determination of carbon in coal is reviewed and assessed. The most favourable method is that based on neutron inelastic scattering. The potential role of on-line carbon analysers in improving boiler efficiency and in carbon accounting is discussed.

A Simplified Control Method for Tie-Line Power of DC Micro-Grid

OpenAIRE

Yanbo Che; Jinhuan Zhou; Tingjun Lin; Wenxun Li; Jianmei Xu

2018-01-01

Compared with the AC micro-grid, the DC micro-grid has low energy loss and no issues of frequency stability, which makes it more accessible for distributed energy. Thus, the DC micro-grid has good potential for development. A variety of renewable energy is included in the DC micro-grid, which is easily affected by the environment, causing fluctuation of the DC voltage. For grid-connected DC micro-grid with droop control strategy, the tie-line power is affected by fluctuations in the DC voltag...

An Energy-Saving Concept of the Smart Building Power Grid with Separated Lines for Standby Devices

Directory of Open Access Journals (Sweden)

Dmytro Zubov

2016-09-01

Full Text Available Standby power takes 5-10 % of the residential electricity around the world. Some countries lose more than 14 % of the total electricity used in the residential sector. Hence, a new energysaving concept that could help to decrease the power losses is discussed in this paper. Firstly, the two power lines of infrastructure for continuously connected equipment and for standby devices is proposed for new smart buildings. Secondly, the segmented infrastructure with unified hardwareunits is proposed for existing smart buildings (the new one can apply this principle as well. The contactors (i.e. unified hardware units consist of the NodeMcu Lua ESP8266 WiFi IoTdevelopment board, ACS712T ELC-30A current sensor, and the Songle relay. The automatic mode is based on three steps: measurement of the current using ACS712T ELC-30A sensor in all segments except the root; switching off the relays with the current less than or equal to any number in the historical data; switching off the root contactor if all the descendent relays (i.e. contactors are switched off. Second step represents the linear classification with sliding window in machine learning. The software consists of two parts, low-level Arduino sketches and high-level C# Windows form app. They are connected by MQTT broker Mosquitto. The proposed concept was successfully tested using a prototype with three segments, one of which includes smart lighting. The payback period is of approximately one month and a half for the whole-building switch concept.

Quantitative on-line age monitoring system for power generation industries

International Nuclear Information System (INIS)

Mukhopadhyay, N.K.; Dutta, B.K.; Kushwaha, H.S.

1994-01-01

The degradation effect of various components of power generation industries is an important information for safe and cost effective running of the plant. Among the various such aging effects, fatigue, fatigue creep interaction and crack growth are commonly responsible for most of the failures. Information about various aging effects help in assessing structural degradation of the components. This provides actual plant transients to future designers, guidelines for in-service inspection and maintenance programmes and may also support future life extension of a power plant. In the present paper, development of a quantitative on-line age monitoring methodology using the available plant instrumentations is presented. Green's function technique is used to convert plant data to temperature and stress versus time data. Fatigue usage factor is computed using rain flow cycle counting algorithm using the material fatigue data. The effect of creep is considered adopting life fraction rule using material creep data. Crack growth rate is predicted using linear elastic fracture mechanics and time dependent C t approach. The present paper describes the detailed steps of this methodology, the development of various codes and the case studies carried out. (author). 3 figs

Analysis methodology for the post-trip return to power steam line break event

Energy Technology Data Exchange (ETDEWEB)

Lee, Chul Shin; Kim, Chul Woo; You, Hyung Keun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1996-06-01

An analysis for Steam Line Break (SLB) events which result in a Return-to-Power (RTP) condition after reactor trip was performed for a postulated Yonggwang Nuclear Power Plant Unit 3 cycle 8. Analysis methodology for post-trip RTP SLB is quite different from that of non-RTP SLB and is more difficult. Therefore, it is necessary to develop a methodology to analyze the response of the NSSS parameters to the post-trip RTP SLB events and the fuel performance after the total reactivity exceeds the criticality. In this analysis, the cases with and without offsite power were simulated crediting 3-D reactivity feedback effect due to a local heatup in the vicinity of stuck CEA and compared with the cases without 3-D reactivity feedback with respect to post-trip fuel performance. Departure-to Nucleate Boiling Ratio (DNBR) and Linear Heat Generation Rate (LHGR). 36 tabs., 32 figs., 11 refs. (Author) .new.

The effects of lightning and high altitude electromagnetic pulse on power distribution lines

Energy Technology Data Exchange (ETDEWEB)

Uman, M.A.; Rubinstein, M.; Yacoub, Z. [Florida Univ., Gainesville, FL (United States)

1995-01-01

We simultaneously recorded the voltages induced by lightning on both ends of an unenergized 448-meter long unenergized electric power line and the lightning vertical electric and horizontal magnetic fields at ground level near the line. The lightning data studied and presented here were due both to cloud lightning and to very close (about 20 m from the line) artificially initiated lightning. For cloud sources, a frequency-domain computer program called EMPLIN was used to calculate induced line voltages as a function of source elevation, angle of incidence, and wave polarization of the radiated cloud discharge pulses in order to compare with the measurements. For very-close lightning, the measured line voltages could be grouped into two categories, those in which multiple, similarly shaped, evenly spaced pulses were observed, which we call oscillatory, and those dominated by a principal pulse with subsidiary oscillations of much smaller amplitude, which we call impulsive. The amplitude of the induced voltage ranged from tens of kilovolts for oscillatory voltages to hundreds of kilovolts for impulsive voltages. A new technique is derived for the calculation of the electromagnetic fields from nearby lightning to ground above an imperfectly conducting ground. This technique was used in conjunction with an existing time domain coupling theory and lightning return stroke model to calculate voltages at either end of the line. The results show fair agreement with the measured oscillatory voltage waveforms if corona is ignored and improved results when corona effects are modeled. The modeling of the impulsive voltage, for which local flashover probably successful. In an attempt to understand better the sources of the line voltages for very close lightning, measurements of the horizontal and vertical electric fields 30 m from triggered lightning were obtained.

Characteristics of a four element gyromagnetic nonlinear transmission line array high power microwave source

Energy Technology Data Exchange (ETDEWEB)

Johnson, J. M., E-mail: jared.johnson@ttu.edu; Reale, D. V.; Garcia, R. S.; Cravey, W. H.; Neuber, A. A.; Dickens, J. C.; Mankowski, J. J. [Center for Pulsed Power and Power Electronics Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States); Krile, J. T. [Department of Electromagnetics and Sensor Systems, Naval Surface Warfare Center - Dahlgren Division, Dahlgren, Virginia 22448 (United States)

2016-05-15

In this paper, a solid-state four element array gyromagnetic nonlinear transmission line high power microwave system is presented as well as a detailed description of its subsystems and general output capabilities. This frequency agile S-band source is easily adjusted from 2-4 GHz by way of a DC driven biasing magnetic field and is capable of generating electric fields of 7.8 kV/m at 10 m correlating to 4.2 MW of RF power with pulse repetition frequencies up to 1 kHz. Beam steering of the array at angles of ±16.7° is also demonstrated, and the associated general radiation pattern is detailed.

Robust suppression of nonstationary power-line interference in electrocardiogram signals

International Nuclear Information System (INIS)

Li, Guojun; Zeng, Xiaopin; Zhou, Yu; Liu, Guojin; Zhou, Xichuan; Zhou, Xiaona

2012-01-01

It is a challenge to suppress time-varying power-line interference (PLI) with various levels in electrocardiogram (ECG) signals. Most previous attempts of tracking and suppressing the nonstationary PLI signal are based on the least-squares (LS) algorithm. This makes these methods susceptible to QRS complex in suppressing a low-level PLI signal which is frequently coupled in battery-operated ECG equipment. To address the limitation of LS-based methods, this study presents a robust PLI suppression system based on a robust extension of the Kalman filter. In addition, we used an improved version of empirical mode decomposition to further attenuate the QRS complex. Experiments show that our system could effectively suppress the PLI while preserving meaningful ECG components at various interference levels. (paper)

A high voltage power line: the route with the least environmental and health impact. Public consultation on the plan to rebuild the 400 kV power line between Lille and Arras

International Nuclear Information System (INIS)

Carlier, Jean-Louis; Chardonnet, Claude

2017-01-01

The upgrade to double-circuit of the 400-kV power line between Avelin and Gavrelle (Northern France) was first set in motion to improve security and to adapt the network to renewable energy sources or energy transition. Since 2011, it has been the object of an unprecedented consultation process, in terms of duration as well as magnitude. From 2012 to 2015, after much discussion, the contracting authority, Reseau Transport d'Electricite (RTE), determined the line with the least consequential environmental and health effects and presented it to the 2016 spring public inquiry. Information and communication requirements were adapted at each stage of the project, to take local concerns into account. Health concerns about the magnetic fields and noise generated by the electric lines were expressed from the very beginning of the consultation and were therefore treated with special care, through knowledge-sharing, debate and specific studies. A health committee, comprising volunteers from various backgrounds, was entrusted with informing the general public and providing suggestions to RTE and the health authorities, through in-depth discussions about health issues. The committee also asked RTE to conduct studies and measure electromagnetic fields to support an informed decision. As a result, the contracting authority defined the route of the electric line based primarily on the distance between houses and the line. The committee also obtained further commitments from RTE to minimize the magnetic fields emitted by the line with a new type of pylon and to monitor the effects on the people living along the line over time. During the course of this consultation process, shared knowledge together with a continuous dialogue on local health concerns aided the search for the route with the least consequential environmental and health impact. (authors)

Power Lines and Crops Can Be Good Neighbors

Energy Technology Data Exchange (ETDEWEB)

None

2010-08-01

Two of the Pacific Northwest’s greatest economic assets are its wealth of agriculture and its clean and reliable electricity fueled largely by hydropower. Sometimes the two intersect. Transmission lines carrying electricity to the region’s farms, businesses and homes must, of necessity, span large areas where people grow crops and orchards. To ensure a safe and reliable flow of electricity across these expanses, trees and other vegetation must be managed to certain standards. At the same time, the Bonneville Power Administration — which owns and operates three-quarters of the region’s high-voltage transmission — recognizes the importance of our region’s agricultural bounty. We are committed to working with individuals and agricultural communities to facilitate ongoing land-use activities in transmission rights-of-way as long as those uses are compatible with transmission safety and reliability standards. Our goal with vegetation management is to keep you and your property safe while protecting the reliability of our region’s electricity system. By working together, BPA and landowners can protect the system and public safety.

Line-Interactive Transformerless Uninterruptible Power Supply (UPS with a Fuel Cell as the Primary Source

Directory of Open Access Journals (Sweden)

Muhammad Iftikhar

2018-03-01

Full Text Available This paper presents line-interactive transformerless Uninterruptible Power Supply (UPS with a fuel cell as the prime energy source. The proposed UPS consists of three major parts (i.e., an output inverter, a unidirectional DC–DC converter, and a battery charger/discharger. Non-isolated topologies of both the unidirectional converter and battery charger/discharger ensure transformerless operation of the UPS system. A new topology of high gain converter is employed for boosting the low voltage of the fuel cell to a higher DC link voltage, with minimum semiconductor count, and high efficiency. A high-gain battery charger/discharger realizes the bidirectional operation between the DC link and the battery bank. Besides, it regulates the DC link voltage during the cold start of fuel cells and keeps the battery bank voltage to only 24 V. A new inverter control scheme is introduced that regulates the output voltage and minimizes the total harmonic distortion for non-linear loading condition. The proposed control scheme integrates proportional-resonant control with slide mode control, which improves the controller’s performance in transient conditions. The proposed UPS system is validated by developing a 1-kVA experimental prototype.

A Possibilistic Approach for the Prediction of the Risk of Interference between Power and Signal Lines Onboard Satellites

Directory of Open Access Journals (Sweden)

Nicola Toscani

2018-01-01

Full Text Available This work presents a hybrid random/fuzzy approach for uncertainty quantification in electromagnetic modelling, which combines probability and possibility theory in order to properly account for both aleatory and epistemic uncertainty, respectively. In particular, a typical intrasystem electromagnetic-compatibility problem in aerospace applications is considered, where some parameters are affected by fabrication tolerances or other kinds of randomness (aleatory uncertainty and others are inherently deterministic but unknown due to human’s lack of knowledge (epistemic uncertainty. Namely, a differential-signal line in a satellite is subject to crosstalk due to a nearby dc power line carrying conducted emissions generated by a dc-dc converter in a wide frequency range (up to 100 MHz. The nonideal features of the signal line (e.g., weak unbalance of terminal loads are treated as random variables (RVs, whereas the mutual position of signal and power line is characterized by possibility theory through suitable fuzzy variables. Such a hybrid approach allows deriving a general and exhaustive description of uncertainty of the target variable of interest, that is, the differential noise voltage induced in the signal line. The obtained results are compared versus a conventional Monte Carlo simulation where all parameters are treated as RVs, and the advantages of the proposed approach (in terms of completeness and richness of information gained about sensitivity of results are highlighted.

Nest occupation and prey grabbing by saker falcon (Falco cherrug on power lines in the province of Vojvodina (Serbia

Directory of Open Access Journals (Sweden)

Puzović S.

2008-01-01

Full Text Available Research on nest occupation and prey grabbing by saker falcon (Falco cherrug on power lines in Vojvodina (Serbia was done in the period from 1986 to 2004. During three specially analyzed periods, saker falcon took the nests of raven (Corvus corax in 91% of a total of 22 cases of nest occupation, and those of hooded crow (Corvus corone cornix in only 9%. Saker falcon regularly grabs prey from different birds that occasionally or constantly spend time around power lines [Kestrel (Falco tinnunculus, hobby (Falco subbuteo, hooded crow (Corvus corone cornix, jack-daw (Corvus monedula, marsh harrier (Circus aeruginosus, hen harrier (Circus cyaneus, buzzard (Buteo buteo, and raven (Corvus corax]. One year a studied pair of saker falcons on a power line in Donji Srem, Serbia grabbed prey from five different species of birds. Out of a total of 40 cases of prey grabbing in the period from January to December, as much 70% of the grabbed prey was taken from kestrel (Falco tinnunculus. During the winter and early spring, prey was grabbed predominantly by males; after May, prey was sometimes grabbed by females as well. Most of the grabbed prey was common vole (Microtus arvalis.

Improving a Power Line Communications Standard with LDPC Codes

Directory of Open Access Journals (Sweden)

Hsu Christine

2007-01-01

Full Text Available We investigate a power line communications (PLC scheme that could be used to enhance the HomePlug 1.0 standard, specifically its ROBO mode which provides modest throughput for the worst case PLC channel. The scheme is based on using a low-density parity-check (LDPC code, in lieu of the concatenated Reed-Solomon and convolutional codes in ROBO mode. The PLC channel is modeled with multipath fading and Middleton's class A noise. Clipping is introduced to mitigate the effect of impulsive noise. A simple and effective method is devised to estimate the variance of the clipped noise for LDPC decoding. Simulation results show that the proposed scheme outperforms the HomePlug 1.0 ROBO mode and has lower computational complexity. The proposed scheme also dispenses with the repetition of information bits in ROBO mode to gain time diversity, resulting in 4-fold increase in physical layer throughput.

Survey of seismic conditions of drilling and blasting operations near overhead electricity power lines

Science.gov (United States)

Korshunov, G. I.; Afanasev, P. I.; Bulbasheva, I. A.

2017-10-01

The monitoring and survey results of drilling and blasting operations are specified during the development of Afanasyevsky deposit of cement raw materials for a 110 kV electricity power lines structure. Seismic explosion waves and air shock waves were registered in the course of monitoring. The dependency of peak particle velocities on the scaled distance and explosive weight by the delay time was obtained.

Expert system in power distribution lines switching; Sistema especialista em manobras de redes de distribuicao de energia eletrica

Energy Technology Data Exchange (ETDEWEB)

Cavellucci, Celso

1989-07-01

This work proposes an expert system integrated to procedures of numerical computation, denominated RD and projected to suggest alternatives of switching plans in the isolation and re-establishment of power distribution lines. The switching plans are based on the specialist's knowledge (network operator) and in evaluations of the electric conditions of the switching. Specialist's knowledge is represented in the form of triples (context, attribute, value) and production rules, that are evaluated conveniently by the machine of inference of the RD system. The electric power distribution is represented by a graph model, where the knots are load blocks and the arcs are key of the system. The evaluation of the electric requirements (voltage drop and physical capacity of the components of the power distribution lines) it is obtained through a maneuver simulator (numeric computation). The maneuver simulator bases on the Method of the Moments for the calculation of the voltage drop. With base in these ideas a prototype of the RD system was developed.

Expert system in power distribution lines switching; Sistema especialista em manobras de redes de distribuicao de energia eletrica

Energy Technology Data Exchange (ETDEWEB)

Cavellucci, Celso

1989-07-01

This work proposes an expert system integrated to procedures of numerical computation, denominated RD and projected to suggest alternatives of switching plans in the isolation and re-establishment of power distribution lines. The switching plans are based on the specialist's knowledge (network operator) and in evaluations of the electric conditions of the switching. Specialist's knowledge is represented in the form of triples (context, attribute, value) and production rules, that are evaluated conveniently by the machine of inference of the RD system. The electric power distribution is represented by a graph model, where the knots are load blocks and the arcs are key of the system. The evaluation of the electric requirements (voltage drop and physical capacity of the components of the power distribution lines) it is obtained through a maneuver simulator (numeric computation). The maneuver simulator bases on the Method of the Moments for the calculation of the voltage drop. With base in these ideas a prototype of the RD system was developed.

Revealing discriminating power of the elements in edible sea salts: Line-intensity correlation analysis from laser-induced plasma emission spectra

Energy Technology Data Exchange (ETDEWEB)

Lee, Yonghoon, E-mail: yhlee@mokpo.ac.kr [Department of Chemistry, Mokpo National University, Jeonnam 534-729 (Korea, Republic of); Ham, Kyung-Sik [Department of Food Engineering, Mokpo National University, Jeonnam 534-729 (Korea, Republic of); Han, Song-Hee [Division of Maritime Transportation System, Mokpo National Maritime University, Jeonnam 530-729 (Korea, Republic of); Yoo, Jonghyun, E-mail: jyoo@appliedspectra.com [Applied Spectra, Inc., 46665 Fremont Boulevard, Fremont, CA 94538 (United States); Jeong, Sungho [School of Mechatronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

2014-11-01

We have investigated the discriminating power of the elements in edible sea salts using Laser-Induced Breakdown Spectroscopy (LIBS). For the ten different sea salts from South Korea, China, Japan, France, Mexico and New Zealand, LIBS spectra were recorded in the spectral range between 190 and 1040 nm, identifying the presence of Na, Cl, K, Ca, Mg, Li, Sr, Al, Si, Ti, Fe, C, O, N, and H. Intensity correlation analysis of the observed emission lines provided a valuable insight into the discriminating power of the different elements in the sea salts. The correlation analysis suggests that the elements with independent discrimination power can be categorized into three groups; those that represent dissolved ions in seawater (K, Li, and Mg), those that are associated with calcified particles (Ca and Sr), and those that are present in soils contained in the sea salts (Al, Si, Ti, and Fe). Classification models using a few emission lines selected based on the results from intensity correlation analysis and full broadband LIBS spectra were developed based on Principal Component Analysis (PCA) and Partial Least Squares-Discriminant Analysis (PLS-DA) and their performances were compared. Our results indicate that effective combination of a few emission lines can provide a dependable model for discriminating the edible sea salts and the performance is not much degraded from that based on the full broadband spectra. This can be rationalized by the intensity correlation results. - Highlights: • Broadband LIBS spectra of various edible sea salts were obtained. • Intensity correlation of emission lines of the elements in edible sea salts was analyzed. • The elements were categorized into three groups with independent discriminating power. • The effective combination of a few lines can provide dependable classification models.

Design and development of line type modulators for high impedance electron gun

Energy Technology Data Exchange (ETDEWEB)

Dixit, Kavita P.; Tillu, Abhijit; Chavan, Ramchandra; Yadav, Vivek; Sarukte, Hemant, E-mail: kavidi@barc.gov.in [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Mumbai (India)

2014-07-01

Conventional line type modulators are routinely used for powering pulsed power microwave devices such as magnetrons and klystrons used for radar, medical and scientific applications. The load impedance (operating point) is fairly well defined in these cases, and makes the design of the discharging circuit of the modulator straight forward. This paper describes the Line type modulators that have been developed and being routinely used for powering the Triode Electron Gun of industrial electron linacs. The beam parameters of such guns are user defined and the pulse current varies from few mA to 800mA (typ). The beam energies requirement varies from 40 keV to 80 keV. Hence the impedance offered by the electron gun to the power source (modulator) is not well defined. The load capacitance which is inclusive of the various stray capacitances along with the intrinsic gun capacitance is ∼ 200-400 pF. This capacitance, which depends on the configuration, shunts the load and makes the effective load highly capacitive with the resistive part varying over a wide range. The paper describes the design and development of conventional line type modulators for powering Electron gun load of the type described above. (author)

Resource Allocation with Adaptive Spread Spectrum OFDM Using 2D Spreading for Power Line Communications

Science.gov (United States)

Baudais, Jean-Yves; Crussière, Matthieu

2007-12-01

Bit-loading techniques based on orthogonal frequency division mutiplexing (OFDM) are frequently used over wireline channels. In the power line context, channel state information can reasonably be obtained at both transmitter and receiver sides, and adaptive loading can advantageously be carried out. In this paper, we propose to apply loading principles to an spread spectrum OFDM (SS-OFDM) waveform which is a multicarrier system using 2D spreading in the time and frequency domains. The presented algorithm handles the subcarriers, spreading codes, bits and energies assignment in order to maximize the data rate and the range of the communication system. The optimization is realized at a target symbol error rate and under spectral mask constraint as usually imposed. The analytical study shows that the merging principle realized by the spreading code improves the rate and the range of the discrete multitone (DMT) system in single and multiuser contexts. Simulations have been run over measured power line communication (PLC) channel responses and highlight that the proposed system is all the more interesting than the received signal-to-noise ratio (SNR) is low.

Analysis and Design of Timing Recovery Schemes for DMT Systems over Indoor Power-Line Channels

Directory of Open Access Journals (Sweden)

Cortés José Antonio

2007-01-01

Full Text Available Discrete multitone (DMT modulation is a suitable technique to cope with main impairments of broadband indoor power-line channels: spectral selectivity and cyclic time variations. Due to the high-density constellations employed to achieve the required bit-rates, synchronization issues became an important concern in these scenarios. This paper analyzes the performance of a conventional DMT timing recovery scheme designed for linear time-invariant (LTI channels when employed over indoor power lines. The influence of the channel cyclic short-term variations and the sampling jitter on the system performance is assessed. Bit-rate degradation due to timing errors is evaluated in a set of measured channels. It is shown that this synchronization mechanism limits the system performance in many residential channels. Two improvements are proposed to avoid this end: a new phase error estimator that takes into account the short-term changes in the channel response, and the introduction of notch filters in the timing recovery loop. Simulations confirm that the new scheme eliminates the bit-rate loss in most situations.

Recovery and updating of power transmission lines. The experience made by ELETROSUL; Recapacitacao e repotenciacao de linhas de transmissao. A experiencia da ELETROSUL

Energy Technology Data Exchange (ETDEWEB)

Stephan, Jose Carlos de Saboia [ELETROSUL, Curitiba, PR (Brazil)]. E-mail: jcsaboia@eletrosul.gov.br

2001-07-01

This document presents a procedures synthesis for analysis and verification of power transmission line adjustments, aiming their recovery or power updating, it also shows the executed procedures during the stages of preliminary design, final design and construction of the modernized transmission lines by ELETROSUL for the 138, 230 and 500 Kv tensions. The concepts on which the evaluation criteria of the structural components for the transmission lines(metallic supports, foundations in metallic grills and reinforced concrete) have been based are presented, as well as the main aspects of the used methodologies for that. It also makes a comparative analysis related to the used processes for structural analyses of the metallic support in trelliswork (computational process which uses the finite element and graphical methods), as well as the foundations of these supports (structural verifications and others). Also are reported the researches and jobs which involved the power updating of the three 138 and 230 kv transmission lines of ELETROSUL.

49 CFR 542.2 - Procedures for selecting low theft light duty truck lines with a majority of major parts...

Science.gov (United States)

2010-10-01

... 49 Transportation 6 2010-10-01 2010-10-01 false Procedures for selecting low theft light duty... TRUCK LINES TO BE COVERED BY THE THEFT PREVENTION STANDARD § 542.2 Procedures for selecting low theft... a low theft rate have major parts interchangeable with a majority of the covered major parts of a...

A state indicator on regional scale for high-voltage power lines: Defining a priority for in situ inspections

International Nuclear Information System (INIS)

Comelli, M.; Colonna, N.; Martini, L.; Licitra, G.

2009-01-01

An integrated system to evaluate the magnetic field generated by power lines exposure has been developed using a specific simulation model (PLEIA-EMF). This is part of a software tool-set, subjected to internal suitability verifications and in-field validations. A state indicator related to each span has been determined using the data extracted from digital cartography, the magnetic field calculated by PLEIA and the number of people living in the nearest buildings. In this way, it is possible to determine eventual criticalities in the considered area, focusing attention on those cases with more considerable exposure levels and involving a higher number of people. A campaign of inspections has been planned using PLEIA simulations. The reliability of stored technical data and the real population exposure levels have been evaluated in critical cases, individuated through the following described methodology. The procedures leading to the indicator determination and the modalities of in situ inspections are here presented. (authors)

High power, high brightness electron beam generation in a pulse-line driven pseudospark discharge

International Nuclear Information System (INIS)

Destler, W.W.; Segalov, Z.; Rodgers, J.; Ramaswamy, K.; Reiser, M.

1993-01-01

High brightness (∼10 10 A/m 2 rad 2 ), high power density (∼10 10 W/cm 2 ) electron beams have been generated by the mating of a hollow-cathode discharge device operating in the pseudospark regime to the output of a high power pulse line accelerator. Very small diameter (∼1 mm) electron beams with currents in the range 500--1000 A and energies in the range 150--300 keV have been generated with effective emittances estimated to be at or below 170 mm mrad. Such emittances are comparable to those achieved in conventional electron beam sources at current densities several orders of magnitude lower than those observed in these experiments

Monitoring for materials fatigue in nuclear power plant

International Nuclear Information System (INIS)

Bartonicek, J.; Hienstorfer, W.

1991-01-01

The pressurizer surge line in unit 1 of the GKN nuclear power station belongs to the safety-relevant systems that have been monitored since the year 1987. The results of this in-service monitoring period show this component part experiences temperature fluctuations that have not been specified in the design documents of GKN 1. The in-service monitoring revealed both local and global temperature changes in the entire surge line, so that the resulting real stresses affecting the surge line can be derived and incorporated in a realistic fatigue analysis. (orig.) [de

Simulation of Standby Efficiency Improvement for a Line Level Control Resonant Converter Based on Solar Power Systems

Directory of Open Access Journals (Sweden)

Ming-Tse Kuo

2015-01-01

Full Text Available This paper proposes a new scheme to improve the standby efficiency of the high-power half-bridge line level control (LLC resonant converter. This new circuit is applicable to improving the efficiency of the renewable energy generation system in distributed power systems. The main purpose is to achieve high-efficiency solar and wind power and stable output under different load conditions. In comparison with the traditional one, this novel method can improve standby efficiency at standby. The system characteristics of this proposed method have been analyzed through detailed simulations, which prove its feasibility.

Final environmental statement. Final addendum to Part II: Manufacture of floating nuclear power plants by Offshore Power Systems. DOCKET-STN--50-437

International Nuclear Information System (INIS)

1978-06-01

This Addendum to Part II of the Final Environmental Statement related to manufacture of floating nuclear power plants by Offshore Power Systems (OPS), NUREG-0056, issued September 1976, was prepared by the U.S. Nuclear Regulatory Commission (NRC), Office of Nuclear Reactor Regulation. The staff's basic evaluation is presented in NUREG-0056. The current Addendum provides further consideration of a number of topics discussed in NUREG-0056, particularly additional consideration of shore zone siting at estuarine and ocean regions. This Summary and Conclusions recapitulates and is cumulative for Part II of the FES and the current Addendum. Augmentations to the Summary and Conclusions presented in Part II of the FES and arising from the evaluations contained in this Addendum are italicized

Conceptual design for transmission line inspection robot

International Nuclear Information System (INIS)

Jalal, M F Abdul; Sahari, K S Mohamed; Anuar, A; Arshad, A D Mohd; Idris, M S

2013-01-01

Power transmission line is used for power distribution purposes due to their cost effective measure compared to underlying cable. However, prolonged exposure to natural weather may cause fatigue stress to the lines as well as induce material failure. Therefore, periodical line inspection is considered uttermost important as a preventive measure to avoid power outage. However, transmission line inspection has always been a high risk and expensive work. Hazardous works that may harm operator as well as routine that requires precise handling can be performed by robots. Various types of robots have been designed and developed for line inspection but only perform well on a straight and continuous line. As these robots encounter an obstacle during the inspection, then the real problem in terms of robot stability and smooth operation arises. In this paper, conceptual design and evaluation for transmission line inspection robot is presented. The inspection robot mobile robot must be able to bypass or avoid obstacles as it travels along the power transmission line.

Corrosion control in electric power plants

International Nuclear Information System (INIS)

Syrett, B.C.

1992-01-01

This paper reports that corrosion of components in power plants costs the US electric power utility industry billions of dollars each year. Through the Electric Power Research Institute's (EPRI) research and development, several approaches have been developed to reduce these huge costs. They include improved materials selection procedures, coatings, cathodic protection, inhibitors, removal of aggressive species from the environment, and on-line corrosion monitoring. In addition, as part of an on-going technology transfer effort, EPRI is developing databases and expert systems that will help utilities obtain corrosion information and guide them in materials selection and failure analysis

Promising lines of investigations in the realms of laboratory astrophysics with the aid of powerful lasers

International Nuclear Information System (INIS)

Belyaev, V. S.; Batishchev, P. A.; Bolshakov, V. V.; Elkin, K. S.; Karabadzhak, G. F.; Kovkov, D. V.; Matafonov, A. P.; Raykunov, G. G.; Yakhin, R. A.; Pikuz, S. A.; Skobelev, I. Yu.; Faenov, A. Ya.; Fortov, V. E.; Krainov, V. P.; Rozanov, V. B.

2013-01-01

The results of work on choosing and substantiating promising lines of research in the realms of laboratory astrophysics with the aid of powerful lasers are presented. These lines of research are determined by the possibility of simulating, under laboratory conditions, problematic processes of presentday astrophysics, such as (i) the generation and evolution of electromagnetic fields in cosmic space and the role of magnetic fields there at various spatial scales; (ii) the mechanisms of formation and evolution of cosmic gamma-ray bursts and relativistic jets; (iii) plasma instabilities in cosmic space and astrophysical objects, plasma jets, and shock waves; (iv) supernova explosions and mechanisms of the explosion of supernovae featuring a collapsing core; (v) nuclear processes in astrophysical objects; (vi) cosmic rays and mechanisms of their production and acceleration to high energies; and (vii) astrophysical sources of x-ray radiation. It is shown that the use of existing powerful lasers characterized by an intensity in the range of 10 18 –10 22 W/cm 2 and a pulse duration of 0.1 to 1 ps and high-energy lasers characterized by an energy in excess of 1 kJ and a pulse duration of 1 to 10 ns makes it possible to perform investigations in laboratory astrophysics along all of the chosen promising lines. The results obtained by experimentally investigating laser plasma with the aid of the laser facility created at Central Research Institute of Machine Building (TsNIIMash) and characterized by a power level of 10 TW demonstrate the potential of such facilities for performing a number of experiments in the realms of laboratory astrophysics.

Technical-parameter calculation model for underground low-power electrical lines and indoor installations used in telecommunications

Directory of Open Access Journals (Sweden)

Henry Bastidas Mora

2011-09-01

Full Text Available This article presents an analysis of electrical distribution theory for 60Hz-lines operating at low voltage, particularly underground lines and residential indoor installations. Such distribution lines’ behaviour is observed as a function of frequency to consider any advantages regarding the potential use of power transmission lines (PTL for transmitting telecommunication signals. A method for computing the secondary parameters is proposed which has been based on the primary parameters, namely inductance, capacitance, conductance and resistance. The secondary parameters so obtained were characteristic impedance, propagation constant (together with its real value and the attenuation constant. Conductor configurations, insulation materials and gauges commonly used in Colombia were verified for such low-voltage lines. A mathematical model is proposed as a theoretical tool for analysing and predicting characteristic impedance pattern and the attenuations which occur at high frequencies, thereby complementing our group’s previous work. Conclusions are drawn, together with a perspective regarding future work and applications.

The Circulation Distribution on the Lifting Line for a Given Extracted Power

Directory of Open Access Journals (Sweden)

Ali Helali

2012-01-01

Full Text Available Presently, there exist few numerical methods which treat the inverse problem for the determination of the geometry of wind turbine blades. In this work, authors intend to solve the inverse optimum project for horizontal axis wind turbine in which the selection of the circulation distribution is obtained by resolving two variational problems: the first consists in sorting the circulation distribution on the lifting line, which, for a given power extracted by the wind turbine, minimizes the loses due to the induced velocity. In the second, the optimal circulation distribution is selected such that the kinetic energy of the wind downstream of the rotor disc is minimum, when the energy extracted by the wind turbine for one rotating period is imposed. A code has been developed which incorporates the real pitch of the helicoidal vortex wake. Very promising results have been obtained: the circulation distribution for a given extracted power and the chord lengths distribution law along the blade span.

Proceedings of the American Power Conference. Volume 58-II

International Nuclear Information System (INIS)

McBride, A.E.

1996-01-01

This book is part 2 of the proceedings of the American Power Conference, Technology for Competition and Globalization, 1996. The topics of the papers include structural plant design; challenges of the global marketplace; thermal hydraulic methods for nuclear power plant safety and operation; decontamination and decommissioning; competitive operations and maintenance; fuel opportunities; cooling; competitive power pricing; operations; transformers; relays; plant controls; training to meet the competitive future; burning technologies; ash and byproducts utilization; advanced systems; computer tools for plant design; globalization of power; power system protection and power quality; life extension; grounding; and transmission line equipment

Line Emission and X-ray Line Polarization of Multiply Ionized Mo Ions

Science.gov (United States)

Petkov, E. E.; Safronova, A. S.; Kantsyrev, V. L.; Shlyaptseva, V. V.; Stafford, A.; Safronova, U. I.; Shrestha, I. K.; Schultz, K. A.; Childers, R.; Cooper, M. C.; Beiersdorfer, P.; Hell, N.; Brown, G. V.

2016-10-01

We present a comprehensive experimental and theoretical study of the line emission from multiply ionized Mo ions produced by two different sets of experiments: at LLNL EBIT and the pulsed power generator Zebra at UNR. Mo line emission and polarization measurements were accomplished at EBIT for the first time. In particular, benchmarking experiments at the LLNL EBIT with Mo ions produced at electron beam energies from 2.75 keV up to 15 keV allowed us to break down these very complicated spectra into spectra with only few ionization stages and to select processes that influence them as well as to measure line polarization. The EBIT data were recorded using the EBIT Calorimeter Spectrometer and a crystal spectrometer with a Ge crystal. X-ray Mo spectra and pinhole images were collected from Z-pinch plasmas produced from various wire loads. Non-LTE modeling, high-precision relativistic atomic and polarization data were used to analyze L-shell Mo spectra. The influence of different plasma processes including electron beams on Mo line radiation is summarized. This work was supported by NNSA under DOE Grant DE-NA0002954. Experiments at the NTF/UNR were funded in part by DE-NA0002075. Work at LLNL was performed under the auspices of the U.S. DOE under contract DE-AC52-07NA27344.

Nuclear power plant simulators for operator licensing and training. Part I. The need for plant-reference simulators. Part II. The use of plant-reference simulators

International Nuclear Information System (INIS)

Rankin, W.L.; Bolton, P.A.; Shikiar, R.; Saari, L.M.

1984-05-01

Part I of this report presents technical justification for the use of plant-reference simulators in the licensing and training of nuclear power plant operators and examines alternatives to the use of plant-reference simulators. The technical rationale is based on research on the use of simulators in other industries, psychological learning and testing principles, expert opinion and user opinion. Part II discusses the central considerations in using plant-reference simulators for licensing examination of nuclear power plant operators and for incorporating simulators into nuclear power plant training programs. Recommendations are presented for the administration of simulator examinations in operator licensing that reflect the goal of maximizing both reliability and validity in the examination process. A series of organizational tasks that promote the acceptance, use, and effectiveness of simulator training as part of the onsite training program is delineated

Line voltage distortions due to operation of the power supply devices required for plasma heating and magnetic field generation in the W7X thermonuclear fusion experiment

International Nuclear Information System (INIS)

Werner, F.

1997-03-01

The operation of the W7-X plasma heating devices requires high voltage DC power supplies with a total electrical power of 40 MVA. For this purpose twelve-pulse AC/DC converters are projected. These converters enforce a non sinusoidal line current, whose harmonics are causing corresponding line voltage distortions. To evaluate the extent of these distortions, the reaction of the harmonic currents on the AC line, is investigated by numerical network analysis. This is done for both, the 20 kV-junction point of the converters and the 110 kV-line terminal of the electricity supply company. Furthermore the design of LC series-resonant circuits, projected for power factor correction and damping of the harmonic content of the line voltage, has been verified. The additional operation of the 1.5 MVA magnet power supplies also contributes, even though to a much smaller extent, to the line voltage distortion. The influence of these twelve-pulse AC/DC converters was investigated too. The numerical calculations have been done with the aid of the network simulation program 'Pspice'. In an equivalent circuit the transmission line network and the transformers are represented by their inductances respectively equivalent inductances. The rectifier units are simulated by a number of current sources, producing the current harmonics in amplitude, frequency and phase. The harmonics amplitudes of the plasma heating power supplies are frequency and phase. The harmonics amplitudes of the plasma heating power supplies are measured values given by the manufacturer. For the magnet power supplies, the harmonics are derived from the theoretical step like I(t) current shape by Fourier series decomposition. Due to the action of the LC circuits the achieved characteristic voltage quality values are far below the permissible values corresponding to the recommendations of VDE 0160. (orig.) [de

Interlaboratory comparison of measuring results of magnetic field near 400 kV overhead power line

Directory of Open Access Journals (Sweden)

Grbić Maja

2012-01-01

Full Text Available The paper presents a comparison of measured results of magnetic field near 400 kV overhead power lines obtained by three laboratories. This interlaboratory comparison was performed to ensure confidence in the quality of the test results. The measured results were analyzed with standard methods, using En number, based on which the evaluation of the laboratories was performed.

Thermal Stress of Surface of Mold Cavities and Parting Line of Silicone Molds

Directory of Open Access Journals (Sweden)

Bajčičák Martin

2014-06-01

Full Text Available The paper is focused on the study of thermal stress of surface of mold cavities and parting line of silicone molds after pouring. The silicone mold White SD - THT was thermally stressed by pouring of ZnAl4Cu3 zinc alloy with pouring cycle 20, 30 and 40 seconds. The most thermally stressed part of surface at each pouring cycle is gating system and mold cavities. It could be further concluded that linear increase of the pouring cycle time leads to the exponential increasing of the maximum temperature of mold surface after its cooling. The elongated pouring cycle increases the temperature accumulated on the surface of cavities and the ability of silicone mold to conduct the heat on its surface decreases, because the low thermal conductivity of silicone molds enables the conduction of larger amount of heat into ambient environment.

The power industry of the Magadan oblast: part of the Leninist GOELRO (State Commission for the Electrification of Russia) plan

Energy Technology Data Exchange (ETDEWEB)

Pozdnyak, I.G.; Anishchenko, Ye.B.

1981-01-01

A brief history is given of the development of the Magadan oblast's power industry, which is inseparably connected with development of the very rich raw material resources and fast development of the mining industry. In 1985 completion of construction of the Kolyma GES is planned; with the end of its construction will begin preparatory work one Ust'-Srednekansk GES: the second GES of the Kalyma falls. Work has begun since 1981 to expand the third phase of the Magadan heat and electric power plant. In 1982 completion of installation of power equipment at the Arkagalinsk State regional power plant is planned. In the 11th five-year plan construction of the system of 220 kV power lines will be finished, and 110 and 35 kV power distribution lines will be built. A special place belongs to construction of the Lankovskaya thermal power plant, which will aid in creating a stable fuel-energy base with a positive future. Chukotka power will be further developed. By 1990, 18 more state farms should be connected to the state power system. Completing the power basis in the Magadan oblast will enable an acceleration in its development, and a rise in the material and cultural standard of living of the people of the Far Northeast.

Power and Frequency Control as it Relates to Wind-Powered Generation

Energy Technology Data Exchange (ETDEWEB)

Lacommare, Kristina S H

2010-12-20

This report is a part of an investigation of the ability of the U.S. power system to accommodate large scale additions of wind generation. The objectives of this report are to describe principles by which large multi-area power systems are controlled and to anticipate how the introduction of large amounts of wind power production might require control protocols to be changed. The operation of a power system is described in terms of primary and secondary control actions. Primary control is fast, autonomous, and provides the first-line corrective action in disturbances; secondary control takes place on a follow-up time scale and manages the deployment of resources to ensure reliable and economic operation. This report anticipates that the present fundamental primary and secondary control protocols will be satisfactory as wind power provides an increasing fraction of the total production, provided that appropriate attention is paid to the timing of primary control response, to short term wind forecasting, and to management of reserves for control action.

DISSECTING THE POWER SOURCES OF LOW-LUMINOSITY EMISSION-LINE GALAXY NUCLEI VIA COMPARISON OF HST-STIS AND GROUND-BASED SPECTRA

Energy Technology Data Exchange (ETDEWEB)

Constantin, Anca; Castillo, Christopher A. [Department of Physics and Astronomy, James Madison University, Harrisonburg, VA 22807 (United States); Shields, Joseph C. [Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Barth, Aaron J. [Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)

2015-12-01

Using a sample of ∼100 nearby line-emitting galaxy nuclei, we have built the currently definitive atlas of spectroscopic measurements of Hα and neighboring emission lines at subarcsecond scales. We employ these data in a quantitative comparison of the nebular emission in Hubble Space Telescope (HST) and ground-based apertures, which offer an order-of-magnitude difference in contrast, and provide new statistical constraints on the degree to which transition objects and low-ionization nuclear emission-line regions (LINERs) are powered by an accreting black hole at ≲10 pc. We show that while the small-aperture observations clearly resolve the nebular emission, the aperture dependence in the line ratios is generally weak, and this can be explained by gradients in the density of the line-emitting gas: the higher densities in the more nuclear regions potentially flatten the excitation gradients, suppressing the forbidden emission. The transition objects show a threefold increase in the incidence of broad Hα emission in the high-resolution data, as well as the strongest density gradients, supporting the composite model for these systems as accreting sources surrounded by star-forming activity. The narrow-line LINERs appear to be the weaker counterparts of the Type 1 LINERs, where the low accretion rates cause the disappearance of the broad-line component. The enhanced sensitivity of the HST observations reveals a 30% increase in the incidence of accretion-powered systems at z ≈ 0. A comparison of the strength of the broad-line emission detected at different epochs implies potential broad-line variability on a decade-long timescale, with at least a factor of three in amplitude.

Urban Power Line Corridors as Novel Habitats for Grassland and Alien Plant Species in South-Western Finland.

Directory of Open Access Journals (Sweden)

Jussi Lampinen

Full Text Available Regularly managed electric power line corridors may provide habitats for both early-successional grassland plant species and disturbance-dependent alien plant species. These habitats are especially important in urban areas, where they can help conserve native grassland species and communities in urban greenspace. However, they can also provide further footholds for potentially invasive alien species that already characterize urban areas. In order to implement power line corridors into urban conservation, it is important to understand which environmental conditions in the corridors favor grassland species and which alien species. Likewise it is important to know whether similar environmental factors in the corridors control the species composition of the two groups. We conducted a vegetation study in a 43 kilometer long urban power line corridor network in south-western Finland, and used generalized linear models and distance-based redundancy analysis to determine which environmental factors best predict the occurrence and composition of grassland and alien plant species in the corridors. The results imply that old corridors on dry soils and steep slopes characterized by a history as open areas and pastures are especially suitable for grassland species. Corridors suitable for alien species, in turn, are characterized by productive soils and abundant light and are surrounded by a dense urban fabric. Factors controlling species composition in the two groups are somewhat correlated, with the most important factors including light abundance, soil moisture, soil calcium concentration and soil productivity. The results have implications for grassland conservation and invasive alien species control in urban areas.

A New Precision Measurement of the Small-scale Line-of-sight Power Spectrum of the Lyα Forest

Science.gov (United States)

Walther, Michael; Hennawi, Joseph F.; Hiss, Hector; Oñorbe, Jose; Lee, Khee-Gan; Rorai, Alberto; O’Meara, John

2018-01-01

We present a new measurement of the Lyα forest power spectrum at 1.8 masking missing data, damped Lyα absorption systems, and metal absorption lines. Our measurement results in unprecedented precision on the small-scale modes k> 0.02 {{s}} {{km}}-1, inaccessible to previous SDSS/BOSS analyses. It is well known that these high-k modes are highly sensitive to the thermal state of the intergalactic medium, but contamination by narrow metal lines is a significant concern. We quantify the effect of metals on the small-scale power and find a modest effect on modes with kmasking metals and restricting to kmasking as our data are generated from Lyα forest simulations. These mock spectra are used to build a custom emulator, enabling us to interpolate between a sparse grid of models and perform Markov chain Monte Carlo fits. Our results agree well with BOSS on scales kdata set for precisely constraining the thermal history of the intergalactic medium, cosmological parameters, and the nature of dark matter. The power spectra and their covariance matrices are provided as electronic tables.

LTPS-TFT Pixel Circuit Compensating for TFT Threshold Voltage Shift and IR-Drop on the Power Line for AMOLED Displays

Directory of Open Access Journals (Sweden)

Ching-Lin Fan

2012-01-01

Full Text Available We propose a new pixel design for the active matrix organic light-emitting diode (AMOLED using low-temperature polycrystalline silicon thin-film transistors (LTPS-TFTs. The proposed pixel is composed of four switching TFTs, one driving TFT (DTFT, and one capacitor. The simulation results are performed by AIM-SPICE software. The error rate of OLED output current with (threshold voltage variation (0.3 V and power line drop by 1 V are improved to about 1.67% and 15%, respectively. Thus, the proposed pixel circuit can successfully overcome drawbacks suffered from DTFT threshold voltage deviation and IR-drop on power line.

18 CFR 16.19 - Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of...

Science.gov (United States)

2010-04-01

... existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power....19 Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power project with a license not subject to sections 14 and 15 of the Federal Power Act. (a...

Resource Allocation with Adaptive Spread Spectrum OFDM Using 2D Spreading for Power Line Communications

Directory of Open Access Journals (Sweden)

Baudais Jean-Yves

2007-01-01

Full Text Available Bit-loading techniques based on orthogonal frequency division mutiplexing (OFDM are frequently used over wireline channels. In the power line context, channel state information can reasonably be obtained at both transmitter and receiver sides, and adaptive loading can advantageously be carried out. In this paper, we propose to apply loading principles to an spread spectrum OFDM (SS-OFDM waveform which is a multicarrier system using 2D spreading in the time and frequency domains. The presented algorithm handles the subcarriers, spreading codes, bits and energies assignment in order to maximize the data rate and the range of the communication system. The optimization is realized at a target symbol error rate and under spectral mask constraint as usually imposed. The analytical study shows that the merging principle realized by the spreading code improves the rate and the range of the discrete multitone (DMT system in single and multiuser contexts. Simulations have been run over measured power line communication (PLC channel responses and highlight that the proposed system is all the more interesting than the received signal-to-noise ratio (SNR is low.

Power plant site evaluation - Douglas Point site. Volume 1, part 2. Final report

International Nuclear Information System (INIS)

1977-11-01

This is part of a series of reports containing an evaluation of the proposed Douglas Point nuclear generating station site located on the Potomac River in Maryland 30 miles south of Washington, DC. This report contains sections on cooling tower air emissions, noise impacts, transmission line effects, radiation from normal releases, site features affecting radiological accidents, and meteorology

Preparation of Power Distribution System for High Penetration of Renewable Energy Part I. Dynamic Voltage Restorer for Voltage Regulation Pat II. Distribution Circuit Modeling and Validation

Science.gov (United States)

Khoshkbar Sadigh, Arash

by simulation and experimental tests under various conditions considering all possible cases such as different amounts of voltage sag depth (VSD), different amounts of point-on-wave (POW) at which voltage sag occurs, harmonic distortion, line frequency variation, and phase jump (PJ). Furthermore, the ripple amount of fundamental voltage amplitude calculated by the proposed method and its error is analyzed considering the line frequency variation together with harmonic distortion. The best and worst detection time of proposed method were measured 1ms and 8.8ms, respectively. Finally, the proposed method has been compared with other voltage sag detection methods available in literature. Part 2: Power System Modeling for Renewable Energy Integration: As power distribution systems are evolving into more complex networks, electrical engineers have to rely on software tools to perform circuit analysis. There are dozens of powerful software tools available in the market to perform the power system studies. Although their main functions are similar, there are differences in features and formatting structures to suit specific applications. This creates challenges for transferring power system circuit models data (PSCMD) between different software and rebuilding the same circuit in the second software environment. The objective of this part of thesis is to develop a Unified Platform (UP) to facilitate transferring PSCMD among different software packages and relieve the challenges of the circuit model conversion process. UP uses a commonly available spreadsheet file with a defined format, for any home software to write data to and for any destination software to read data from, via a script-based application called PSCMD transfer application. The main considerations in developing the UP are to minimize manual intervention and import a one-line diagram into the destination software or export it from the source software, with all details to allow load flow, short circuit and

Reactive power compensator

Science.gov (United States)

El-Sharkawi, Mohamed A.; Venkata, Subrahmanyam S.; Chen, Mingliang; Andexler, George; Huang, Tony

1992-01-01

A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation.

Reactive power compensator

Energy Technology Data Exchange (ETDEWEB)

El-Sharkawi, Mohamed A. (Renton, WA); Venkata, Subrahmanyam S. (Woodinville, WA); Chen, Mingliang (Kirkland, WA); Andexler, George (Everett, WA); Huang, Tony (Seattle, WA)

1992-01-01

A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation.

On-line acoustic monitoring of EDF nuclear plants in operation and loose-part diagnosis

International Nuclear Information System (INIS)

Morel, J.L.; Puyal, C.

1991-05-01

In order to detect incipient failures in nuclear power plant components, EDF has now put into operation more than 50 loose-part monitoring systems, on its 900 MW and 1 300 MW units. This paper first reviews the experience gained on the 900 MW reactors in recent years. It then focuses on the 1 300 MW loose part monitoring system (IDEAL) and to the tools developed for the diagnosis off site within a specific Expertise Laboratory at the Research and Development Division. New studies have been undertaken within the Monitoring and Aid to Diagnosis Station (PSAD) in order to extend the capabilities of loose part diagnosis on site. The new tools here presented integrate the recent progress in acquisition technology (SMART system) and in artificial intelligence (MIGRE expert system)

49 CFR Appendix C to Part 541 - Criteria for Selecting Light Duty Truck Lines Likely To Have High Theft Rates

Science.gov (United States)

2010-10-01

... Likely To Have High Theft Rates C Appendix C to Part 541 Transportation Other Regulations Relating to... MOTOR VEHICLE THEFT PREVENTION STANDARD Pt. 541, App. C Appendix C to Part 541—Criteria for Selecting Light Duty Truck Lines Likely To Have High Theft Rates Scope These criteria specify the factors the...

Sierra Pacific Power Company Alturas Transmission Line Project, Final Environmental Impact Report/Environmental Impact Statement. Volume 3: Appendices

International Nuclear Information System (INIS)

1995-11-01

Sierra Pacific Power Company has proposed the construction and operation of a 345,000 volt overhead electric power transmission line from Alturas, California to Reno, Nevada. This Environmental Impact Report/Environmental Impact Statement will assess the potential environmental impacts of the proposed project and alternatives. This report contains Appendices A--I which contain the following: glossary/abbreviations; scoping report; structure coordinate summary; air quality; biological resources; geology; noise; visual contrast rating forms; and cultural resources

Nuclear power in long term energy strategies in Macedonia

International Nuclear Information System (INIS)

Volkanovski, A.

2001-01-01

The Macedonian Power System (MPS) used to be a part of the former Yugoslav Power System, and it was connected to the European system by 400 kV transmission lines. at the present time, the MPS works isolated from the UCPTE, only connected to the Yugoslav and Greek power systems. The connections with the Bulgarian and Albanian power systems are on a lower voltage level. The reliability and stability of the MPS needs to be improved. Macedonia is located in the central area of the Balkan, where the transmission lines from other Balkan countries are crossing. In the near future, the Macedonian Power System needs to be linked to the European system. To prepare for the energy demand at the beginning of the 21-st century, when the local coal reserves get exhausted, Macedonia needs to start with activities for substitution of the existing coal-fired thermal power plants with nuclear plants. This paper discusses the activities for global development solutions in the area of power generation. (author)

Calculation and reduction of the sound emissions of overhead power lines

International Nuclear Information System (INIS)

Straumann, U.

2007-01-01

In this dissertation, Ulrich Straumann of the Swiss Federal Institute of Technology in Zurich, Switzerland, discusses the reduction of sound emissions from overhead power lines. Corona-discharges occur during wet weather or when foggy or icing conditions prevail. Apart from these wide-band crackling noises, low-frequency, tonal emissions also occur. The CONOR (Corona Noise Reduction) project examined these emissions at a frequency of twice the mains frequency and looked for economically feasible solutions to the problems caused by them. The source of these emissions and the mechanisms causing them are discussed. Also, ways of calculating their strength are presented. The effects of varying cable geometry and construction are discussed, as are hydrophilic coatings that could be used to reduce sound emissions.

Operating experience with KRAFTWERK UNION cementation line

International Nuclear Information System (INIS)

Podmaka, L.; Tomik, L.

1988-01-01

A facility is described designed for fixation in a cement matrix of the radioactive concentrate produced by thickening waste water from the Bohunice nuclear power plant. The cementation line output is 0.6 m 3 concentrate/h. The concentrate is put in 200 l drums. The individual operating units, cement management, air conditioning, dosimetric monitoring and the building part are described. The requirements for the operators and the assessment of the quality of raw materials and the product are discussed. (M.D.). 3 figs., 4 refs

Development of electric power transmission line anomaly approaching alarm system. Sodensen ijo sekkin keiho sochi no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Kusaba, Masaro; Tabata, Takatoshi; Miyazaki, Shusuke [Kyushu Electric Power Co., Inc., Fukuoka (Japan)

1989-03-30

In order to plan preventive measures from the occurrence of electric power transmission line accident, a power transmission line anomaly approaching alarm system was developed to automatically alarm the operators and surveillants. The surveillance system, composed of camera, surveillance unit proper and alarm receiving portion, generates alarm and indicate hazard to the operators, when animal invades a hazardous area designated on the monitor. Wireless telegraph for the alarm transmission use used frequency around a 322MHz band with the Radio Ray law and preventive measures from noise, taken into consideration. The prototype is characterized by unnecessary ancillary fitting to the surveillance object, rare erroneous operations and high reliability. While the hazardous area can be simply designated, changed and released, as made by volume on the control panel. It is moreover easy to designate, as done by confirming the surveillance object on the display. It is also possible in multidimensional surveillance and easy to use on site. 7 figs.

A technical note about Phidel: A new software for evaluating magnetic induction field generated by power lines

International Nuclear Information System (INIS)

Comelli, M.; Benes, M.; Bampo, A.; Villalta, R.

2007-01-01

The Regional Environment Protection Agency of Friuli Venezia Giulia (ARPA FVG, Italy) has performed an analysis on existing software designed to calculate magnetic induction field generated by power lines. As far as the agency's requirements are concerned the tested programs display some difficulties in the immediate processing of electrical and geometrical data supplied by plant owners, and in certain cases turn out to be inadequate in representing complex configurations of power lines. Phidel, an innovative software, tackles and works out all the above-mentioned problems. Therefore, the obtained results, when compared with those of other programs, are the closest to experimental measurements. The output data can be employed both in the GIS and Excel environments, allowing the immediate overlaying of digital cartography and the determining of the 3 and 10 μT bands, in compliance with the Italian Decree of the President of the Council of Ministers of 8 July 2003. (authors)

A Novel Method To On-Line Monitor Reactor Nuclear Power And In-Core Thermal Environments

International Nuclear Information System (INIS)

Liu, Hanying; Miller, Don W.; Li, Dongxu; Radcliff, Thomas D.

2002-01-01

dynamic performance in the compensation mode. Therefore, a theoretical second order model was developed based on the structure of the sensor. The input variable in the developed second order model is technically transformed in order to easily determine the sensor transfer function. The sensor is also simulated using a numerical model. The simulation results are compared with the theoretical model in terms of the relation between the sensor dynamics and the thermal environment variables. This comparison verifies the feasibility of the proposed method using the compensation mode to on-line monitor in-core thermal environments and using the measurement mode to on-line measure nuclear power. (authors)

Diagnosis and on-line displacement monitoring for critical pipe of fossil power plant

Energy Technology Data Exchange (ETDEWEB)

Heo, J. S.; Hyun, J. S. [Korea Electric Power Corporation, Seoul (Korea, Republic of); Heo, J. R.; Lee, S. K.; Cho, S. Y. [Korea South-East Power Co., Ltd., Seoul (Korea, Republic of)

2009-07-01

High temperature steam pipes of fossil power plant are subject to a severe thermal range and usually operates well into the creep range. Cyclic operation of the plant subjects the piping system to mechanical and thermal fatigue mechanisms and poor or malfunctional support assemblies can impose massive loads or stress onto the piping system. In order to prevent the serious damage and failure of the critical pipe system, various inspection methods such as visual inspection, computational analysis and on-line piping displacement monitoring were developed. 3-Dimensional piping displacement monitoring system was developed with using he aluminum alloy rod and rotary encoder type sensors, this system was installed and operated on the 'Y' fossil power plant successfully. It is expected that this study will contribute to the safety of piping system, which could minimize stress and extend the actual life of critical piping.

Proceedings of the switched power workshop

International Nuclear Information System (INIS)

Fernow, R.C.

1988-01-01

These proceedings contain most of the presentations given at a workshop on the current state of research in techniques for switched power acceleration. The proceedings are divided, as was the workshop itself, into two parts. Part 1, contains the latest results from a number of groups active in switched power research. The major topic here is a method for switching externally supplied power onto a transmission line. Advocates for vacuum photodiode switching, solid state switching, gas switching, and synthetic pulse generation are all presented. Other important areas of research described in this section concern: external electrical and laser pulsing systems; the properties of the created electromagnetic pulse; structures used for transporting the electromagnetic pulse to the region where the electron beam is located; and possible applications. Part 2 of the proceedings considers the problem of designing a high brightness electron gun using switched power as the power source. This is an important first step in demonstrating the usefulness of switched power techniques for accelerator physics. In addition such a gun could have immediate practical importance for advanced acceleration studies since the brightness could exceed that of present sources by several orders of magnitude. I would like to take this opportunity to thank Kathleen Tuohy and Patricia Tuttle for their assistance in organizing and running the workshop. Their tireless efforts contribute greatly to a very productive meeting

LCLS Maximum Credible Beam Power

International Nuclear Information System (INIS)

Clendenin, J.

2005-01-01

The maximum credible beam power is defined as the highest credible average beam power that the accelerator can deliver to the point in question, given the laws of physics, the beam line design, and assuming all protection devices have failed. For a new accelerator project, the official maximum credible beam power is determined by project staff in consultation with the Radiation Physics Department, after examining the arguments and evidence presented by the appropriate accelerator physicist(s) and beam line engineers. The definitive parameter becomes part of the project's safety envelope. This technical note will first review the studies that were done for the Gun Test Facility (GTF) at SSRL, where a photoinjector similar to the one proposed for the LCLS is being tested. In Section 3 the maximum charge out of the gun for a single rf pulse is calculated. In Section 4, PARMELA simulations are used to track the beam from the gun to the end of the photoinjector. Finally in Section 5 the beam through the matching section and injected into Linac-1 is discussed

Clean nuclear power (2. part)

International Nuclear Information System (INIS)

Rocherolles, R.

1998-01-01

The 450 nuclear power plants which produce 24% of world electricity do not generate greenhouse gas effects, but 8,000 tonnes per year of irradiated, radioactive fuel. The first article which was published in the July-August 1997 issue of this journal, described the composition and management of these fuels. This article wish to show the advantage of 'advanced re-processing', which would separate fission products from actinides, in order to incinerate them separately in dedicated fuels and reactors, which, from an ecological point of view, seems more efficient than burying them underground in deep, geological layers. To rid the planet of waste which is continuing to build up, the first step is to build 'incinerators' which will eliminate fission products by slow neutron assisted neutronic capture, and actinides by fast neutron assisted fission. Various projects have been set up, in particular, in Los Alamos, Japan and the CERN. The Carlo Rubbia hybrid machine operating on the well-known thorium cycle is the most advanced project. An incinerator connected up to standard PWR reactor produces no actinide, and reduces the existing stock of plutonium. However, the proper solution, obviously, is to no longer produce waste along with power; second generation nuclear fission will do this. The CERN team bas studied a clean reactor, producing practically no actinides, or fission products, more or less. Thus, the solution to the problem of waste is at hand, and nuclear power will be cleaner that all other types of power. The world market opening up to clean nuclear power is about 1,300 Gigawatts, or 1,300 plants of 1,000 Megawatts. Remarkable progress is taking place under our very eyes; soon we will have clean power in sufficient quantities, at a lower cost than that of other forms of power. (authors)

Wild Horse 69-kV transmission line environmental assessment

International Nuclear Information System (INIS)

1996-12-01

Hill County Electric Cooperative Inc. (Hill County) proposes to construct and operate a 69-kV transmission line from its North Gildford Substation in Montana north to the Canadian border. A vicinity project area map is enclosed as a figure. TransCanada Power Corporation (TCP), a Canadian power-marketing company, will own and construct the connecting 69-kV line from the international border to Express Pipeline's pump station at Wild Horse, Alberta. This Environmental Assessment is prepared for the Department of Energy (DOE) as lead federal agency to comply with the requirements of the National Environmental Policy Act (NEPA), as part of DOE's review and approval process of the applications filed by Hill County for a DOE Presidential Permit and License to Export Electricity to a foreign country. The purpose of the proposed line is to supply electric energy to a crude oil pump station in Canada, owned by Express Pipeline Ltd. (Express). The pipeline would transport Canadian-produced oil from Hardisty, Alberta, Canada, to Caster, Wyoming. The Express Pipeline is scheduled to be constructed in 1996--97 and will supply crude oil to refineries in Wyoming and the midwest

Wild Horse 69-kV transmission line environmental assessment

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-01

Hill County Electric Cooperative Inc. (Hill County) proposes to construct and operate a 69-kV transmission line from its North Gildford Substation in Montana north to the Canadian border. A vicinity project area map is enclosed as a figure. TransCanada Power Corporation (TCP), a Canadian power-marketing company, will own and construct the connecting 69-kV line from the international border to Express Pipeline`s pump station at Wild Horse, Alberta. This Environmental Assessment is prepared for the Department of Energy (DOE) as lead federal agency to comply with the requirements of the National Environmental Policy Act (NEPA), as part of DOE`s review and approval process of the applications filed by Hill County for a DOE Presidential Permit and License to Export Electricity to a foreign country. The purpose of the proposed line is to supply electric energy to a crude oil pump station in Canada, owned by Express Pipeline Ltd. (Express). The pipeline would transport Canadian-produced oil from Hardisty, Alberta, Canada, to Caster, Wyoming. The Express Pipeline is scheduled to be constructed in 1996--97 and will supply crude oil to refineries in Wyoming and the midwest.

Westinghouse Electric Company experiences in chemistry on-line monitoring in Eastern European nuclear power plants

International Nuclear Information System (INIS)

Balavage, J.

2001-01-01

Westinghouse Electric Company has provided a number of Chemistry On-Line Monitoring (OLM) Systems to Nuclear Power Plants in Eastern Europe. Eleven systems were provided to the Temelin Nuclear Power Plant in the south of the Czech Republic. Four systems were provided to the Russian NPP at Novovoronezh. In addition, a system design was developed for primary side chemistry monitoring for units 5 and 6 of another eastern European VVER. The status of the Temelin OLM systems is discussed including updates to the Temelin designs, and the other Eastern European installations and designs are also described briefly. Some of the problems encountered and lessons learned from these projects are also discussed. (R.P.)

Satellite Power Systems (SPS) concept definition study, exhibit C. Volume 2, part 1: System engineering