Grid-connected solar electricity going mainstream

International Nuclear Information System (INIS)

MacLellan, I.

2004-01-01

In 20 days, the sun provides the equivalent amount of energy found in all known fossil fuel reserves. This paper provides an outline of solar energy industry activities from the perspective of Arise Technologies, a Canadian-based solar energy company. An overview of the company's vision and marketing strategy was presented, including annual sales. Details of the company's commercial projects were reviewed, with specific reference to the first Canadian grid-connected solar electric subdivision. An introduction to photovoltaic electricity (PV) as an environmentally positive energy source was presented. Statistics included information on the current solar market worldwide as well as government and industry investment. Portable solar energy applications were provided, as well as grid-tied products in relation to private dwelling and commercial, industrial and institutional buildings. Details of an Arise solar home were presented. An outline of the Technology Early Action Measures (TEAM) was presented, with reference to the federal government's Climate Change Action Plan. The benefits of solar economics were given. PV factory production was overviewed, with a presentation of the experience curve and the number of grid-connected solar electric homes globally. Top global PV manufacturers were listed as well as a chart of world energy transitions underlining the emergence of renewable energy programs and systems. A summary of solar energy in Japan was provided, along with details of mid and long term solar energy planning, as well as other projects around the world. Canadian investment in PV was compared with other countries and details of past government spending on other energy sources were also presented. It was concluded that Canada was far behind other G-8 countries with reference to grid-connected PV, but that off-grid PV was a real business in Canada. It was also concluded that Japan would represent the first real mainstream grid-connected market, followed by Europe

Grid-connected solar electricity going mainstream

Energy Technology Data Exchange (ETDEWEB)

MacLellan, I. [Arise Technologies Corp., Kitchener, ON (Canada)

2004-06-01

In 20 days, the sun provides the equivalent amount of energy found in all known fossil fuel reserves. This paper provides an outline of solar energy industry activities from the perspective of Arise Technologies, a Canadian-based solar energy company. An overview of the company's vision and marketing strategy was presented, including annual sales. Details of the company's commercial projects were reviewed, with specific reference to the first Canadian grid-connected solar electric subdivision. An introduction to photovoltaic electricity (PV) as an environmentally positive energy source was presented. Statistics included information on the current solar market worldwide as well as government and industry investment. Portable solar energy applications were provided, as well as grid-tied products in relation to private dwelling and commercial, industrial and institutional buildings. Details of an Arise solar home were presented. An outline of the Technology Early Action Measures (TEAM) was presented, with reference to the federal government's Climate Change Action Plan. The benefits of solar economics were given. PV factory production was overviewed, with a presentation of the experience curve and the number of grid-connected solar electric homes globally. Top global PV manufacturers were listed as well as a chart of world energy transitions underlining the emergence of renewable energy programs and systems. A summary of solar energy in Japan was provided, along with details of mid and long term solar energy planning, as well as other projects around the world. Canadian investment in PV was compared with other countries and details of past government spending on other energy sources were also presented. It was concluded that Canada was far behind other G-8 countries with reference to grid-connected PV, but that off-grid PV was a real business in Canada. It was also concluded that Japan would represent the first real mainstream grid-connected market

Electrical connection for aluminium conductors in automotive applications : Prestudy of available solutions for electrical connection methods of aluminium cables

OpenAIRE

Hamedi, Emilia

2017-01-01

Due to increasing weight of electrical component and wiring harnesses in a vehicle contrary to the demand of light constructed vehicles as well as the constantly increasing and fluctuating price of copper compared to aluminium’s stable and far lower price, the use of aluminium conductors as an alternative have been promoted.  This thesis work lay theoretical research of the available methods used for electrical connection of aluminium conductors in order to increase the knowledge about the av...

Model Predictive Control for Connected Hybrid Electric Vehicles

Directory of Open Access Journals (Sweden)

Kaijiang Yu

2015-01-01

Full Text Available This paper presents a new model predictive control system for connected hybrid electric vehicles to improve fuel economy. The new features of this study are as follows. First, the battery charge and discharge profile and the driving velocity profile are simultaneously optimized. One is energy management for HEV for Pbatt; the other is for the energy consumption minimizing problem of acc control of two vehicles. Second, a system for connected hybrid electric vehicles has been developed considering varying drag coefficients and the road gradients. Third, the fuel model of a typical hybrid electric vehicle is developed using the maps of the engine efficiency characteristics. Fourth, simulations and analysis (under different parameters, i.e., road conditions, vehicle state of charge, etc. are conducted to verify the effectiveness of the method to achieve higher fuel efficiency. The model predictive control problem is solved using numerical computation method: continuation and generalized minimum residual method. Computer simulation results reveal improvements in fuel economy using the proposed control method.

Nuclear qualified in-containment electrical connectors and method of connecting electrical conductors

Science.gov (United States)

Powell, J. G.

1991-01-01

A nuclear qualified in-containment electrical connection comprises an insulated, sheathed instrument lead having electrical conductors extending from one end thereof to provide two exposed lead wires, a watertight cable having electrical conducting wires therein and extending from one end of the cable to provide two lead wires therefrom, two butt splice connectors each connecting the ends of respective ones of the lead wires from the instrument lead and cable, a length of heat shrinkable plastic tubing positioned over each butt splice connector and an adjacent portion of a respective lead wire from the cable and heat shrunk into position, a length of heat shrinkable plastic tubing on the end portion of the instrument lead adjacent the lead wires therefrom and heat shrunk thereon and a length of outer heat shrinkable plastic tubing extending over the end portion of the instrument lead and the heat shrinkable tubing thereon and over the butt splice connectors and a portion of the cable adjacent the cable lead lines, the outer heat shrinkable tubing being heat shrunk into sealing position on the instrument lead and cable.

Making the Connection between Environmental Science and Decision Making

Science.gov (United States)

Woodhouse, C. A.; Crimmins, M.; Ferguson, D. B.; Garfin, G. M.; Scott, C. A.

2011-12-01

As society is confronted with population growth, limited resources, and the impacts of climate variability and change, it is vital that institutions of higher education promote the development of professionals who can work with decision-makers to incorporate scientific information into environmental planning and management. Skills for the communication of science are essential, but equally important is the ability to understand decision-making contexts and engage with resource managers and policy makers. It is increasingly being recognized that people who understand the linkages between science and decision making are crucial if science is to better support planning and policy. A new graduate-level seminar, "Making the Connection between Environmental Science and Decision Making," is a core course for a new post-baccalaureate certificate program, Connecting Environmental Science and Decision Making at the University of Arizona. The goal of the course is to provide students with a basic understanding of the dynamics between scientists and decision makers that result in scientific information being incorporated into environmental planning, policy, and management decisions. Through readings from the environmental and social sciences, policy, and planning literature, the course explores concepts including scientific information supply and demand, boundary organizations, co-production of knowledge, platforms for engagement, and knowledge networks. Visiting speakers help students understand some of the challenges of incorporating scientific information into planning and decision making within institutional and political contexts. The course also includes practical aspects of two-way communication via written, oral, and graphical presentations as well as through the interview process to facilitate the transfer of scientific information to decision makers as well as to broader audiences. We aspire to help students develop techniques that improve communication and

Decision-making in electrical appliance use in the home

International Nuclear Information System (INIS)

Yamamoto, Yoshihiro; Suzuki, Akihiko; Fuwa, Yasuhiro; Sato, Tomohiro

2008-01-01

This paper presents the results of a survey as well as an argument from the viewpoint of behavioral economics with the aim of clarifying how consumers make decisions about electrical appliance use in the home. A survey of consumers showed that most have little awareness of the energy efficiency of appliances, the price of the services produced by electrical appliances, or electricity rates. These findings indicate that price does not function as a signal in electricity consumption through electrical appliance use. Rather, we found that consumer decision-making in electricity consumption is dependent on the characteristics of the particular electrical appliances they use. Additionally, we argue that the payment system for home electricity consumption plays an important role in decision-making, causing biases due to aspects of human psychology discussed here in terms of satisficing and heuristics, payment decoupling, and budgeting. We conclude that decision-making about electrical appliance use and electricity consumption in the home is not always rational and is affected both by the particular characteristics of appliances and the payment system for electricity consumption along with human psychology

Electrical impedance along connective tissue planes associated with acupuncture meridians

Directory of Open Access Journals (Sweden)

Hammerschlag Richard

2005-05-01

Full Text Available Abstract Background Acupuncture points and meridians are commonly believed to possess unique electrical properties. The experimental support for this claim is limited given the technical and methodological shortcomings of prior studies. Recent studies indicate a correspondence between acupuncture meridians and connective tissue planes. We hypothesized that segments of acupuncture meridians that are associated with loose connective tissue planes (between muscles or between muscle and bone visible by ultrasound have greater electrical conductance (less electrical impedance than non-meridian, parallel control segments. Methods We used a four-electrode method to measure the electrical impedance along segments of the Pericardium and Spleen meridians and corresponding parallel control segments in 23 human subjects. Meridian segments were determined by palpation and proportional measurements. Connective tissue planes underlying those segments were imaged with an ultrasound scanner. Along each meridian segment, four gold-plated needles were inserted along a straight line and used as electrodes. A parallel series of four control needles were placed 0.8 cm medial to the meridian needles. For each set of four needles, a 3.3 kHz alternating (AC constant amplitude current was introduced at three different amplitudes (20, 40, and 80 μAmps to the outer two needles, while the voltage was measured between the inner two needles. Tissue impedance between the two inner needles was calculated based on Ohm's law (ratio of voltage to current intensity. Results At the Pericardium location, mean tissue impedance was significantly lower at meridian segments (70.4 ± 5.7 Ω compared with control segments (75.0 ± 5.9 Ω (p = 0.0003. At the Spleen location, mean impedance for meridian (67.8 ± 6.8 Ω and control segments (68.5 ± 7.5 Ω were not significantly different (p = 0.70. Conclusion Tissue impedance was on average lower along the Pericardium meridian, but not

Enhancing Undergraduate Chemistry Learning by Helping Students Make Connections among Multiple Graphical Representations

Science.gov (United States)

Rau, Martina A.

2015-01-01

Multiple representations are ubiquitous in chemistry education. To benefit from multiple representations, students have to make connections between them. However, connection making is a difficult task for students. Prior research shows that supporting connection making enhances students' learning in math and science domains. Most prior research…

The electrical connection of offshore windparks - technology and investment costs

International Nuclear Information System (INIS)

Busch, R.; Schultz, W.; Unger, C.; Diedrichs, V.

1996-01-01

In order to reach an acceptable cost level for wind energy generated in off-shore wind farms, the consideration of the electrical grid connection is much more important than for on-shore sites. This connection was investigated under technical as well as financial aspects leading to different concepts for different sizes of windfarms. (Author)

The nature and quality of the mathematical connections teachers make

Directory of Open Access Journals (Sweden)

Michael K. Mhlolo

2012-05-01

Full Text Available Current reforms in mathematics education emphasise the need for pedagogy because it offers learners opportunities to develop their proficiency with complex high-level cognitive processes. One has always associated the ability to make mathematical connections, together with the teacher’s role in teaching them, with deep mathematical understanding. This article examines the nature and quality of the mathematical connections that the teachers’ representations of those connections enabled or constrained. The researchers made video recordings of four Grade 11 teachers as they taught a series of five lessons on algebra-related topics. The results showed that the teachers’ representations of mathematical connections were either faulty or superficial in most cases. It compromised the learners’ opportunities for making meaningful mathematical connections. The researchers concluded by suggesting that helping teachers to build their representation repertoires could increase the effectiveness of their instructional practices.

Global distribution of grid connected electrical energy storage systems

Directory of Open Access Journals (Sweden)

Katja Buss

2016-06-01

Full Text Available This article gives an overview of grid connected electrical energy storage systems worldwide, based on public available data. Technologies considered in this study are pumped hydroelectric energy storage (PHES, compressed air energy storage (CAES, sodium-sulfur batteries (NaS, lead-acid batteries, redox-flow batteries, nickel-cadmium batteries (NiCd and lithium-ion batteries. As the research indicates, the worldwide installed capacity of grid connected electrical energy storage systems is approximately 154 GW. This corresponds to a share of 5.5 % of the worldwide installed generation capacity. Furthermore, the article gives an overview of the historical development of installed and used storage systems worldwide. Subsequently, the focus is on each considered technology concerning the current storage size, number of plants and location. In summary it can be stated, PHES is the most commonly used technology worldwide, whereas electrochemical technologies are increasingly gaining in importance. Regarding the distribution of grid connected storage systems reveals the share of installed storage capacity is in Europe and Eastern Asia twice as high as in North America.

Electrical bushing for a superconductor element

Science.gov (United States)

Mirebeau, Pierre; Lallouet, Nicolas; Delplace, Sebastien; Lapierre, Regis

2010-05-04

The invention relates to an electrical bushing serving to make a connection at ambient temperature to a superconductor element situated in an enclosure at cryogenic temperature. The electrical bushing passes successively through an enclosure at intermediate temperature between ambient temperature and cryogenic temperature, and an enclosure at ambient temperature, and it comprises a central electrical conductor surrounded by an electrically insulating sheath. According to the invention, an electrically conductive screen connected to ground potential surrounds the insulating sheath over a section that extends from the end of the bushing that is in contact with the enclosure at cryogenic temperature at least as far as the junction between the enclosure at intermediate temperature and the enclosure at ambient temperature. The invention is more particularly applicable to making a connection to a superconductor cable.

A generative modeling approach to connectivity-Electrical conduction in vascular networks

DEFF Research Database (Denmark)

Hald, Bjørn Olav

2016-01-01

The physiology of biological structures is inherently dynamic and emerges from the interaction and assembly of large collections of small entities. The extent of coupled entities complicates modeling and increases computational load. Here, microvascular networks are used to present a novel...... to synchronize vessel tone across the vast distances within a network. We hypothesize that electrical conduction capacity is delimited by the size of vascular structures and connectivity of the network. Generation and simulation of series of dynamical models of electrical spread within vascular networks...... of different size and composition showed that (1) Conduction is enhanced in models harboring long and thin endothelial cells that couple preferentially along the longitudinal axis. (2) Conduction across a branch point depends on endothelial connectivity between branches. (3) Low connectivity sub...

Dust-Tolerant Intelligent Electrical Connection System

Science.gov (United States)

Lewis, Mark; Dokos, Adam; Perotti, Jose; Calle, Carlos; Mueller, Robert; Bastin, Gary; Carlson, Jeffrey; Townsend, Ivan, III; Immer, Chirstopher; Medelius, Pedro

2012-01-01

Faults in wiring systems are a serious concern for the aerospace and aeronautic (commercial, military, and civilian) industries. Circuit failures and vehicle accidents have occurred and have been attributed to faulty wiring created by open and/or short circuits. Often, such circuit failures occur due to vibration during vehicle launch or operation. Therefore, developing non-intrusive fault-tolerant techniques is necessary to detect circuit faults and automatically route signals through alternate recovery paths while the vehicle or lunar surface systems equipment is in operation. Electrical connector concepts combining dust mitigation strategies and cable diagnostic technologies have significant application for lunar and Martian surface systems, as well as for dusty terrestrial applications. The dust-tolerant intelligent electrical connection system has several novel concepts and unique features. It combines intelligent cable diagnostics (health monitoring) and automatic circuit routing capabilities into a dust-tolerant electrical umbilical. It retrofits a clamshell protective dust cover to an existing connector for reduced gravity operation, and features a universal connector housing with three styles of dust protection: inverted cap, rotating cap, and clamshell. It uses a self-healing membrane as a dust barrier for electrical connectors where required, while also combining lotus leaf technology for applications where a dust-resistant coating providing low surface tension is needed to mitigate Van der Waals forces, thereby disallowing dust particle adhesion to connector surfaces. It also permits using a ruggedized iris mechanism with an embedded electrodynamic dust shield as a dust barrier for electrical connectors where required.

Making Connections: Where STEM Learning and Earth Science Data Services Meet

Science.gov (United States)

Bugbee, Kaylin; Ramachandran, Rahul; Maskey, Manil; Gatlin, Patrick; Weigel, Amanda

2016-01-01

STEM (Science, Technology, Engineering, Mathematics) learning is most effective when students are encouraged to see the connections between science, technology and real world problems. Helping to make these connections has become an increasingly important aspect of Earth Science data research. The Global Hydrology Resource Center (GHRC), one of NASA's 12 EOSDIS (Earth Observing System Data Information System) data centers, has developed a new type of documentation called the micro article to facilitate making connections between data and Earth science research problems.

Making Complex Electrically Conductive Patterns on Cloth

Science.gov (United States)

Chu, Andrew; Fink, Patrick W.; Dobbins, Justin A.; Lin, Greg Y.; Scully, Robert C.; Trevino, Robert

2008-01-01

A method for automated fabrication of flexible, electrically conductive patterns on cloth substrates has been demonstrated. Products developed using this method, or related prior methods, are instances of a technology known as 'e-textiles,' in which electrically conductive patterns ar formed in, and on, textiles. For many applications, including high-speed digital circuits, antennas, and radio frequency (RF) circuits, an e-textile method should be capable of providing high surface conductivity, tight tolerances for control of characteristic impedances, and geometrically complex conductive patterns. Unlike prior methods, the present method satisfies all three of these criteria. Typical patterns can include such circuit structures as RF transmission lines, antennas, filters, and other conductive patterns equivalent to those of conventional printed circuits. The present method overcomes the limitations of the prior methods for forming the equivalent of printed circuits on cloth. A typical fabrication process according to the present method involves selecting the appropriate conductive and non-conductive fabric layers to build the e-textile circuit. The present method uses commercially available woven conductive cloth with established surface conductivity specifications. Dielectric constant, loss tangent, and thickness are some of the parameters to be considered for the non-conductive fabric layers. The circuit design of the conductive woven fabric is secured onto a non-conductive fabric layer using sewing, embroidery, and/or adhesive means. The portion of the conductive fabric that is not part of the circuit is next cut from the desired circuit using an automated machine such as a printed-circuit-board milling machine or a laser cutting machine. Fiducials can be used to align the circuit and the cutting machine. Multilayer circuits can be built starting with the inner layer and using conductive thread to make electrical connections between layers.

Making a personal connection in the medical interview.

Science.gov (United States)

Sessions, Donald G

2009-01-01

The medical interview is an access point for contacting patients at the core of their being. Patients with concernfull medical problems initially and unreflectively grasp these conflicted situations directly in terms of their meaning for the self. The situation and the self can become fused transparently. Physicians can facilitate patients awareness of their core self which is separate from their medical issue, by creating an opportunity for patients to experience the core of being that they mutually share. In the medical interview the possibility of making a personal connection with the patient is already present in the context of the presupposed shared history of a caring relationship between patients and physicians. The physician's gift of presence, of riveted attention and silence as the patient describes her concerns, can create an opening for awareness of their mutual involvement in a common web of concerns at a profound level. Being attuned initially can be reinforced by attending to perceptual domains. The hearing that listens and the seeing that can result in vision can allow for inspiration. Touching with gentleness is a primal mode of knowing and understanding. Words themselves can have great salutary power. Who has not wondered at the "tingle" that occurs during the reading of a powerful poem? What if you do make a personal connection with patients? What if you don't? Even though there is little scientific evidence or statistics to ground the assertion that there is value in a profound relationship I maintain that it is a way to follow the path you have chosen. It is the distinction between a job and a calling. It also lightens the burden we carry in our continual conflict with the increasing pressure of technology, third parties, and the other which is 'other.' Making a personal connection with patients is not about the "trickle down" of humanity from physicians to patients. Personal connection is inspiring to physicians and patients and enlightening

MODELING OF SYMMETRIC THREE-PHASE ASYNCHRONOUS ELECTRIC MOTOR IN ASYMMETRIC CONNECTION TO NETWORK

Directory of Open Access Journals (Sweden)

V. I. Lukovnikov

2005-01-01

Full Text Available The paper shows how to solve the problem concerning reveal of changes in mathematical models and electric parameters of symmetric three-phase short-circuited asynchronous electric motors in case of their connection to single- or two-phase network in comparison with their connection to three-phase network. The uniform methodological approach permitting to generalize the known data and receive new results is offered in the paper.

Making Connections among Multiple Visual Representations: How Do Sense-Making Skills and Perceptual Fluency Relate to Learning of Chemistry Knowledge?

Science.gov (United States)

Rau, Martina A.

2018-01-01

To learn content knowledge in science, technology, engineering, and math domains, students need to make connections among visual representations. This article considers two kinds of connection-making skills: (1) "sense-making skills" that allow students to verbally explain mappings among representations and (2) "perceptual…

Electrical contacts principles and applications

CERN Document Server

Slade, Paul G

2013-01-01

Covering the theory, application, and testing of contact materials, Electrical Contacts: Principles and Applications, Second Edition introduces a thorough discussion on making electric contact and contact interface conduction; presents a general outline of, and measurement techniques for, important corrosion mechanisms; considers the results of contact wear when plug-in connections are made and broken; investigates the effect of thin noble metal plating on electronic connections; and relates crucial considerations for making high- and low-power contact joints. It examines contact use in switch

Nuclear power's effects on electric rate making

International Nuclear Information System (INIS)

Smith, D.S.; Lancaster, A.A.

1978-01-01

Government and the electric utility industry are re-evaluating nuclear power's contribution to the total U.S. energy supplies. This article addresses how the recently increased nuclear plant construction and operation costs are translated into the prices that consumers pay for electricity. The electric rates that consumers pay must reflect the costs of producing electricity, as well as the costs of transmission, distribution, metering, and billing. The use of nuclear power for electric production is anticipated to grow rapidly so as to meet a larger portion of our country's electricity needs through the end of the century; so nuclear power costs are expected to be an even larger portion of the total electricity price. There are certain rate-making issues that are actively being discussed in public forums and before state and Federal regulatory bodies. These issues are not unique to nuclear power, but take on added significance when nuclear power is used by utilities to produce electricity because of the technology required and because of the type, timing, and magnitude of the costs involved. These are: (1) inclusion of construction work in progress in the rate base; (2) fuel adjustment clauses and treatment of nuclear fuel cycle costs; (3) treatment of certain taxes under the rate-making method called normalization or deferral accounting (sometimes referred to as ''phantom taxes''); and (4) rate treatment for particular nuclear expense items reflecting costs of delays, plant cancellations, and operational slowdowns

Creating the electric energy mix of a non-connected Aegean island

Science.gov (United States)

Stamou, Paraskevi; Karali, Sophia; Chalakatevaki, Maria; Daniil, Vasiliki; Tzouka, Katerina; Dimitriadis, Panayiotis; Iliopoulou, Theano; Papanicolaou, Panos; Koutsoyiannis, Demetris; Mamasis, Nikos

2017-04-01

As the electric energy in the non-connected islands is mainly produced by oil-fueled power plants, the unit cost is extremely high. Here the various energy sources are examined in order to create the appropriate electric energy mix for a non-connected Aegean island. All energy sources (renewable and fossil fuels) are examined and each one is evaluated using technical, environmental and economic criteria. Finally the most appropriate energy sources are simulated considering the corresponding energy works. Special emphasis is given to the use of biomass and the possibility of replacing (even partially) the existing oil-fueled power plant. Finally, a synthesis of various energy sources is presented that satisfies the electric energy demand taking into account the base and peak electric loads of the island. Acknowledgement: This research is conducted within the frame of the undergraduate course "Stochastic Methods in Water Resources" of the National Technical University of Athens (NTUA). The School of Civil Engineering of NTUA provided moral support for the participation of the students in the Assembly.

Impact of defects on electrical connectivity of monolayer of ideally aligned rods

International Nuclear Information System (INIS)

Tarasevich, Yu Yu; Dubinin, D O; Laptev, V V; Lebovka, N I

2016-01-01

The processes of formation of electrically conductive films filled by aligned elongated nanoparticles, i.e. nanotubes, nanowires or fibers attract great attention in nanotecnological applications. The alignment can be controlled by external electric fields, evaporation-driven self-assembly and assisted by different other techniques. This work studies the impact of defects on electrical connectivity of ideally aligned monolayer of rods (k-mers). By means of Monte Carlo simulation the problem of percolation for conductive rods on a discrete insulating substrate (square lattice) is analyzed. The aspect ratio of the particles changes within the interval 1-64, the insulating defects were distributed both on the lattice and on the particles. We found that even a very small amount of the insulating defects on the particles can destroy the electrical connectivity. The critical concentration of the defects decreases as the aspect ratio of the particles increases. (paper)

Identification of Synchronous Generator Electric Parameters Connected to the Distribution Grid

Directory of Open Access Journals (Sweden)

Frolov M. Yu.

2017-04-01

Full Text Available According to modern trends, the power grids with distributed generation will have an open system architecture. It means that active consumers, owners of distributed power units, including mobile units, must have free access to the grid, like when using internet, so it is necessary to have plug and play technologies. Thanks to them, the system will be able to identify the unit type and the unit parameters. Therefore, the main aim of research, described in the paper, was to develop and research a new method of electric parameters identification of synchronous generator. The main feature of the proposed method is that parameter identification is performed while the generator to the grid, so it fits in the technological process of operation of the machine and does not influence on the connection time of the machine. For the implementation of the method, it is not necessary to create dangerous operation modes for the machine or to have additional expensive equipment and it can be used for salient pole machines and round rotor machines. The parameter identification accuracy can be achieved by more accurate account of electromechanical transient process, and making of overdetermined system with many more numbers of equations. Parameter identification will be made with each generator connection to the grid. Comparing data obtained from each connection, the middle values can be find by numerical method, and thus, each subsequent identification will accurate the machine parameters.

Endocannabinoid release modulates electrical coupling between CCK cells connected via chemical and electrical synapses in CA1

Directory of Open Access Journals (Sweden)

Jonathan eIball

2011-11-01

Full Text Available Electrical coupling between some subclasses of interneurons is thought to promote coordinated firing that generates rhythmic synchronous activity in cortical regions. Synaptic activity of cholesystokinin (CCK interneurons which co-express cannbinoid type-1 (CB1 receptors are powerful modulators of network activity via the actions of endocannabinoids. We investigated the modulatory actions of endocannabinoids between chemically and electrically connected synapses of CCK cells using paired whole-cell recordings combined with biocytin and double immunofluorescence labelling in acute slices of rat hippocampus at P18-20 days. CA1 stratum radiatum CCK Schaffer collateral associated (SCA cells were coupled electrically with each other as well as CCK basket cells and CCK cells with axonal projections expanding to dentate gyrus. Approximately 50% of electrically coupled cells received facilitating, asynchronously released IPSPs that curtailed the steady-state coupling coefficient by 57%. Tonic CB1 receptor activity which reduces inhibition enhanced electrical coupling between cells that were connected via chemical and electrical synapses. Blocking CB1 receptors with antagonist, AM-251 (5M resulted in the synchronized release of larger IPSPs and this enhanced inhibition further reduced the steady-state coupling coefficient by 85%. Depolarization induced suppression of inhibition (DSI, maintained the asynchronicity of IPSP latency, but reduced IPSP amplitudes by 95% and enhanced the steady-state coupling coefficient by 104% and IPSP duration by 200%. However, DSI did not did not enhance electrical coupling at purely electrical synapses. These data suggest that different morphological subclasses of CCK interneurons are interconnected via gap junctions. The synergy between the chemical and electrical coupling between CCK cells probably plays a role in activity-dependent endocannabinoid modulation of rhythmic synchronization.

Characteristic Analysis of DC Electric Railway Systems with Superconducting Power Cables Connecting Power Substations

Science.gov (United States)

Ohsaki, H.; Matsushita, N.; Koseki, T.; Tomita, M.

2014-05-01

The application of superconducting power cables to DC electric railway systems has been studied. It could leads to an effective use of regenerative brake, improved energy efficiency, effective load sharing among the substations, etc. In this study, an electric circuit model of a DC feeding system is built and numerical simulation is carried out using MATLAB-Simulink software. A modified electric circuit model with an AC power grid connection taken into account is also created to simulate the influence of the grid connection. The analyses have proved that a certain amount of energy can be conserved by introducing superconducting cables, and that electric load distribution and concentration among the substations depend on the substation output voltage distribution.

Characteristic analysis of DC electric railway systems with superconducting power cables connecting power substations

International Nuclear Information System (INIS)

Ohsaki, H; Matsushita, N; Koseki, T; Tomita, M

2014-01-01

The application of superconducting power cables to DC electric railway systems has been studied. It could leads to an effective use of regenerative brake, improved energy efficiency, effective load sharing among the substations, etc. In this study, an electric circuit model of a DC feeding system is built and numerical simulation is carried out using MATLAB-Simulink software. A modified electric circuit model with an AC power grid connection taken into account is also created to simulate the influence of the grid connection. The analyses have proved that a certain amount of energy can be conserved by introducing superconducting cables, and that electric load distribution and concentration among the substations depend on the substation output voltage distribution.

A CONTROLLABLE MICROSWITCH, A METHOD OF MAKING IT, AND USE OF SUCH A MICROSWITCH

DEFF Research Database (Denmark)

1996-01-01

A controllable microswitch comprises a closed cavity having a plurality of contact electrodes, a movable switch body capable of making and breaking an electrical connection between the contact electrodes, and a plurality of control electrodes capable of generating an electrical field to control t...... to an electrical voltage source and for remote-controlled connection and disconnection of an electrical apparatus.......A controllable microswitch comprises a closed cavity having a plurality of contact electrodes, a movable switch body capable of making and breaking an electrical connection between the contact electrodes, and a plurality of control electrodes capable of generating an electrical field to control...... the position of the switch body. The switch body is formed by a diaphragm which is provided with a conducting surface and which divides the cavity into two subcavities. A method of making such a microswitch is moreover disclosed. The microswitch may be used for power regulation of systems connected...

FWPA was heard in the Parliament in connection to the new Electricity Market Act

International Nuclear Information System (INIS)

Holttinen, E.

1998-01-01

The new Electricity Market Act now under preparation will give the private consumers the opportunity to choose their electricity supplier. In principle, this has already been possible before, but the need for an expensive household metering has made it unfeasible. In the new proposal the pricing will be based on so called 'consumer type load curves', and no extra metering is needed. Finnish Wind Power Association was heard in the Economy Committee of the Parliament in connection to the preparation of the new Act. The Association expressed its concern on the unequal market position of small electricity producers connected to medium voltage grid, compared to large producers connected to high voltage grid. At present, the benefits of so called embedded generation are often not reflected in the transfer prices of small scale production, and the prices vary remarkably depending on the grid company. Some of the grid companies effectively prohibit the installations of wind turbines - or any other small scale production plants - in their area, by applying unreasonably high transfer prices. The resources of the electricity market supervisory authorities have shown to be completely inadequate to guarantee fair competition in the Finnish electricity market. (author)

Endocannabinoid Release Modulates Electrical Coupling between CCK Cells Connected via Chemical and Electrical Synapses in CA1

Science.gov (United States)

Iball, Jonathan; Ali, Afia B.

2011-01-01

Electrical coupling between some subclasses of interneurons is thought to promote coordinated firing that generates rhythmic synchronous activity in cortical regions. Synaptic activity of cholecystokinin (CCK) interneurons which co-express cannabinoid type-1 (CB1) receptors are powerful modulators of network activity via the actions of endocannabinoids. We investigated the modulatory actions of endocannabinoids between chemically and electrically connected synapses of CCK cells using paired whole-cell recordings combined with biocytin and double immunofluorescence labeling in acute slices of rat hippocampus at P18–20 days. CA1 stratum radiatum CCK Schaffer collateral-associated cells were coupled electrically with each other as well as CCK basket cells and CCK cells with axonal projections expanding to dentate gyrus. Approximately 50% of electrically coupled cells received facilitating, asynchronously released inhibitory postsynaptic potential (IPSPs) that curtailed the steady-state coupling coefficient by 57%. Tonic CB1 receptor activity which reduces inhibition enhanced electrical coupling between cells that were connected via chemical and electrical synapses. Blocking CB1 receptors with antagonist, AM-251 (5 μM) resulted in the synchronized release of larger IPSPs and this enhanced inhibition further reduced the steady-state coupling coefficient by 85%. Depolarization induced suppression of inhibition (DSI), maintained the asynchronicity of IPSP latency, but reduced IPSP amplitudes by 95% and enhanced the steady-state coupling coefficient by 104% and IPSP duration by 200%. However, DSI did not did not enhance electrical coupling at purely electrical synapses. These data suggest that different morphological subclasses of CCK interneurons are interconnected via gap junctions. The synergy between the chemical and electrical coupling between CCK cells probably plays a role in activity-dependent endocannabinoid modulation of rhythmic synchronization. PMID

Decision making in the electricity sector using performance indicators

Energy Technology Data Exchange (ETDEWEB)

Domingues, Nuno [ISEL-ADESPA, Lisbon (Portugal); FCT-UNL, Caparica (Portugal); Neves-Silva, Rui; Melo, Joao Joanaz de [FCT-UNL, Caparica (Portugal)

2017-02-15

The studies on the electricity sector are usually focused on the supply side, considering consumers as price-takers, i.e. assuming no demand elasticity. The present paper highlights the role of consumers on the electricity sector, assuming that consumers react to electricity prices and make decisions. Many studies focused on the demand side disaggregate consumers by activities, leading to a highly complex analyse. In the present paper, consumers are divided by three main types. In the present paper, the Government makes decisions on the measures to implement to influence the production and the consumption. To study the impact of the Government decisions, the present paper studies and implements a tool: a decision support system. This tool is based on a conceptual model and assists the task of test and analyse the electricity sector using scenarios to obtain a set of performance indicators that would allow to make quantitative balance and to eliminate unfeasible measures. The performance indicators quantify the technical, environmental, social and economical aspects of the electricity sector and help to understand the effect of consumer practices, production technology and Government measures on the electricity sector. Based on the scenarios produced, it is possible to conclude that the price signal is important for consumers and it is a way to guide their behaviour. It is also possible to conclude that is preferable to apply incentives on supporting energy-efficiency measures implementation than on reduce the price of electricity sold to consumers. (orig.)

Decision making in the electricity sector using performance indicators

International Nuclear Information System (INIS)

Domingues, Nuno; Neves-Silva, Rui; Melo, Joao Joanaz de

2017-01-01

The studies on the electricity sector are usually focused on the supply side, considering consumers as price-takers, i.e. assuming no demand elasticity. The present paper highlights the role of consumers on the electricity sector, assuming that consumers react to electricity prices and make decisions. Many studies focused on the demand side disaggregate consumers by activities, leading to a highly complex analyse. In the present paper, consumers are divided by three main types. In the present paper, the Government makes decisions on the measures to implement to influence the production and the consumption. To study the impact of the Government decisions, the present paper studies and implements a tool: a decision support system. This tool is based on a conceptual model and assists the task of test and analyse the electricity sector using scenarios to obtain a set of performance indicators that would allow to make quantitative balance and to eliminate unfeasible measures. The performance indicators quantify the technical, environmental, social and economical aspects of the electricity sector and help to understand the effect of consumer practices, production technology and Government measures on the electricity sector. Based on the scenarios produced, it is possible to conclude that the price signal is important for consumers and it is a way to guide their behaviour. It is also possible to conclude that is preferable to apply incentives on supporting energy-efficiency measures implementation than on reduce the price of electricity sold to consumers. (orig.)

Novel wind powered electric vehicle charging station with vehicle-to-grid (V2G) connection capability

International Nuclear Information System (INIS)

Fathabadi, Hassan

2017-01-01

Highlights: • The only wind powered EV charging station reported in the literature. • The charging station maximally converts wind energy into electric energy. • Novel fast and highly accurate MPPT technique implemented in the EV charging station. • The charging station is grid-connected type with vehicle-to-grid (V2G) technology. • The charging station balances load demand in the grid connected to it. - Abstract: In this study, a novel grid-connected wind powered electric vehicle (EV) charging station with vehicle-to-grid (V2G) technology is designed and constructed. The wind powered EV charging station consists of a wind energy conversion system (WECS), a unidirectional DC/DC converter connected to the WECS, a maximum power point tracking (MPPT) controller, 15 bidirectional DC/DC converters dedicated to 15 charging stations provided for charging EVs, and a three-phase bidirectional DC/AC inverter connected to the grid. The contribution of this work is that the grid-connected wind powered EV charging station presented in this work is the only constructed EV charging station reported in the literature that uses wind energy as a renewable resource to produce electric energy for charging EVs, and moreover, it maximally converts wind energy into electric energy because it uses a novel fast and highly accurate MPPT technique proposed in this study. Other works are only simulated models without any new MPPT consideration. It is demonstrated that the constructed wind powered EV charging station is a perfect charging station that not only produces electric energy to charge EVs but also balances load demand in the grid connected to it.

Electrical system studies for the grid connection of wind farms

International Nuclear Information System (INIS)

Arp, K.; Hanson, J.; Hopp, S.; Zimmermann, W.

2007-01-01

Wind power is gaining momentum in the world's energy balance. Several issues have to be addressed whenever power-generating devices are connected to the grid. The paper describes studies needed to evaluate the influence of wind farms on the connected transmission system and how faults in the system impact on induction generators in a wind farm. Some generalized results of studies for an offshore wind farm in the North Sea and a Bulgarian wind farm show how studies can influence the layout of the internal network and the electrical equipment. (authors)

Grid-connected photovoltaic (PV) systems with batteries storage as solution to electrical grid outages in Burkina Faso

International Nuclear Information System (INIS)

Abdoulaye, D; Koalaga, Z; Zougmore, F

2012-01-01

This paper deals with a key solution for power outages problem experienced by many African countries and this through grid-connected photovoltaic (PV) systems with batteries storage. African grids are characterized by an insufficient power supply and frequent interruptions. Due to this fact, users who especially use classical grid-connected photovoltaic systems are unable to profit from their installation even if there is sun. In this study, we suggest the using of a grid-connected photovoltaic system with batteries storage as a solution to these problems. This photovoltaic system works by injecting the surplus of electricity production into grid and can also deliver electricity as a stand-alone system with all security needed. To achieve our study objectives, firstly we conducted a survey of a real situation of one African electrical grid, the case of Burkina Faso (SONABEL: National Electricity Company of Burkina). Secondly, as study case, we undertake a sizing, a modeling and a simulation of a grid-connected PV system with batteries storage for the LAME laboratory at the University of Ouagadougou. The simulation shows that the proposed grid-connected system allows users to profit from their photovoltaic installation at any time even if the public electrical grid has some failures either during the day or at night.

Fault detection of the connection of lithium-ion power batteries based on entropy for electric vehicles

Science.gov (United States)

Yao, Lei; Wang, Zhenpo; Ma, Jun

2015-10-01

This paper proposes a method of fault detection of the connection of Lithium-Ion batteries based on entropy for electric vehicle. In electric vehicle operation process, some factors, such as road conditions, driving habits, vehicle performance, always affect batteries by vibration, which easily cause loosing or virtual connection between batteries. Through the simulation of the battery charging and discharging experiment under vibration environment, the data of voltage fluctuation can be obtained. Meanwhile, an optimal filtering method is adopted using discrete cosine filter method to analyze the characteristics of system noise, based on the voltage set when batteries are working under different vibration frequency. Experimental data processed by filtering is analyzed based on local Shannon entropy, ensemble Shannon entropy and sample entropy. And the best way to find a method of fault detection of the connection of lithium-ion batteries based on entropy is presented for electric vehicle. The experimental data shows that ensemble Shannon entropy can predict the accurate time and the location of battery connection failure in real time. Besides electric-vehicle industry, this method can also be used in other areas in complex vibration environment.

Modeling Electric Vehicle Benefits Connected to Smart Grids

International Nuclear Information System (INIS)

Stadler, Michael; Marnay, Chris; Mendes, Goncalo; Kloess, Maximillian; Cardoso, Goncalo; Megel, Olivier; Siddiqui, Afzal

2011-01-01

Connecting electric storage technologies to smartgrids will have substantial implications in building energy systems. Local storage will enable demand response. Mobile storage devices in electric vehicles (EVs) are in direct competition with conventional stationary sources at the building. EVs will change the financial as well as environmental attractiveness of on-site generation (e.g. PV, or fuel cells). In order to examine the impact of EVs on building energy costs and CO2 emissions in 2020, a distributed-energy-resources adoption problem is formulated as a mixed-integer linear program with minimization of annual building energy costs or CO2 emissions. The mixed-integer linear program is applied to a set of 139 different commercial buildings in California and example results as well as the aggregated economic and environmental benefits are reported. The research shows that considering second life of EV batteries might be very beneficial for commercial buildings.

Modeling Electric Vehicle Benefits Connected to Smart Grids

Energy Technology Data Exchange (ETDEWEB)

Stadler, Michael; Marnay, Chris; Mendes, Goncalo; Kloess, Maximillian; Cardoso, Goncalo; M& #233; gel, Olivier; Siddiqui, Afzal

2011-07-01

Connecting electric storage technologies to smartgrids will have substantial implications in building energy systems. Local storage will enable demand response. Mobile storage devices in electric vehicles (EVs) are in direct competition with conventional stationary sources at the building. EVs will change the financial as well as environmental attractiveness of on-site generation (e.g. PV, or fuel cells). In order to examine the impact of EVs on building energy costs and CO2 emissions in 2020, a distributed-energy-resources adoption problem is formulated as a mixed-integer linear program with minimization of annual building energy costs or CO2 emissions. The mixed-integer linear program is applied to a set of 139 different commercial buildings in California and example results as well as the aggregated economic and environmental benefits are reported. The research shows that considering second life of EV batteries might be very beneficial for commercial buildings.

Forecasting and decision-making in electricity markets with focus on wind energy

DEFF Research Database (Denmark)

Jónsson, Tryggvi

This thesis deals with analysis, forecasting and decision making in liberalised electricity markets. Particular focus is on wind power, its interaction with the market and the daily decision making of wind power generators. Among recently emerged renewable energy generation technologies, wind power...... derivation of practically applicable tools for decision making highly relevant. The main characteristics of wind power differ fundamentally from those of conventional thermal power. Its effective generation capacity varies over time and is directly dependent on the weather. This dependency makes future...... has become the global leader in terms of installed capacity and advancement. This makes wind power an ideal candidate to analyse the impact of growing renewable energy generation capacity on the electricity markets. Furthermore, its present status of a significant supplier of electricity makes...

Making connections

NARCIS (Netherlands)

Marion Duimel

2007-01-01

Original title: Verbinding maken; senioren en internet. More and more older people are finding their way to the Internet. Many people aged over 50 who have only recently gone online say that a new world has opened up for them. By connecting to the Internet they have the feeling that they

Making the connection: The B.C. Hydro electric system and how it is operated

International Nuclear Information System (INIS)

1993-01-01

British Columbia Hydro supplies electric energy to 93% of the province's population through an integrated electric system. Of the electricity supplied, 95% is generated at 29 hydroelectric plants, with the remainder coming from thermal plants burning fossil fuels. BC Hydro's high voltage transmission and distribution network consists of 17,600 km of lines 60 kV and above and 51,400 km of lines below 60 kV. A description of system operations begins with the principles of hydroelectric generation, with a brief note on thermal generation for peaking or short-term energy production. Non-power operations measures designed to minimize environmental impacts and enhance social benefits are also outlined along with electricity trade with other provinces and the USA. Planning of long- and short-term system operations is also reviewed. An analysis of system components is presented for the Peace, Columbia, Lower Mainland/Coastal/Fraser, and Vancouver Island regions. Finally, information is given on the 29 hydroelectric and 3 thermal plants, including drainage basin, reservoir description and map, inflow, capacity, turbine type, storage, operating constraints, and average energy capability. 51 figs

Making connections: Where STEM learning and Earth science data services meet

Science.gov (United States)

Bugbee, K.; Ramachandran, R.; Maskey, M.; Gatlin, P. N.; Weigel, A. M.

2016-12-01

STEM learning is most effective when students are encouraged to see the connections between science, technology and real world problems. Helping to make these connections has become an increasingly important aspect of Earth science data research. The Global Hydrology Resource Center (GHRC), one of NASA's 12 EOSDIS data centers, has developed a new type of documentation called the micro article to facilitate making connections between data and Earth science research problems. Micro articles are short academic texts that enable a reader to quickly understand a scientific phenomena, a case study, or an instrument used to collect data. While originally designed to increase data discovery and usability, micro articles also serve as a reliable starting point for project-based learning, an educational approach in STEM education, for high school and higher education environments. This presentation will highlight micro articles at the Global Hydrology Resource Center data center and will demonstrate the potential applications of micro articles in project-based learning.

On the electrical contact and long-term behavior of compression-type connections with conventional and high-temperature conductor ropes with low sag

International Nuclear Information System (INIS)

Hildmann, Christian

2016-01-01

In Germany and in Europe it is due to the ''Energiewende'' necessary to transmit more electrical energy with existing overhead transmission lines. One possible technical solution to reach this aim is the use of high temperature low sag conductors (HTLS-conductors). Compared to the common Aluminium Conductor Steel Reinforced (ACSR), HTLS-conductors have higher rated currents and rated temperatures. Thus the electrical connections for HTLS-conductors are stressed to higher temperatures too. These components are most important for the safe and reliable operation of an overhead transmission line. Besides other connection technologies, hexagonal compression connections with ordinary transmission line conductors have proven themselves since decades. From the literature, mostly empirical studies with electrical tests for compression connections are known. The electrical contact behaviour, i.e. the quality of the electrical contact after assembly, of these connections has been investigated insufficiently. This work presents and enhances an electrical model of compression connections, so that the electrical contact behaviour can be determined more accurate. Based on this, principal considerations on the current distribution in the compression connection and its influence on the connection resistance are presented. As a result from the theoretical and the experimental work, recommendations for the design of hexagonal compression connections for transmission line conductors were developed. Furthermore it is known from the functional principle of compression type connections, that the electrical contact behaviour can be influenced from their form fit, force fit and cold welding. In particular the forces in compression connections have been calculated up to now by approximation. The known analytical calculations simplify the geometry and material behaviour and do not consider the correct mechanical load during assembly. For these reasons the joining process

Mounting Thin Samples For Electrical Measurements

Science.gov (United States)

Matus, L. G.; Summers, R. L.

1988-01-01

New method for mounting thin sample for electrical measurements involves use of vacuum chuck to hold a ceramic mounting plate, which holds sample. Contacts on mounting plate establish electrical connection to sample. Used to make electrical measurements over temperature range from 77 to 1,000 K and does not introduce distortions into magnetic field during Hall measurements.

THE ANALYSIS OF STRUCTURAL RELIABILITY OF THE MAIN ELECTRIC CONNECTION CIRCUITS OF NUCLEAR POWER PLANTS

Directory of Open Access Journals (Sweden)

M. A. Korotkevich

2017-01-01

Full Text Available The reliability of the main circuit of electrical connections at a nuclear electric power plant that has two units with a capacity of 1,200 MW each has been determined. Reliability, economical, maneuverable properties of the atomic power plant under study are largely determined by its main circuit, so the choice of the circuit for the design and its status in the process of operation occur to be critical objectives. Main electrical connection circuits in nuclear electric power plants are selected on the basis of the schematic networks of the energy system and the land attached to the plant. The circuit of the connection of a nuclear power plant to the grid in the original normal operating modes at all stages of the construction of such a plant should provide the outcome of the full added capacity of a nuclear power plant and the preservation of its stability in the power system without the influence of the emergency system automatics when any outgoing transmission line is disabled. When selecting the main circuit the individual capacity of the installed units and their number are taken into account as well as the order of development of the plant and power supply system; the voltage on which the power of a plant is delivered; a shortcircuit current for switchgear high voltage and the need for their limitation by circuit means; the most power that can be lost when damage to any switch. A model of reliability of the main circuit of electrical connections is designed to detect all types of accidents that are possible at the coincidence of failures of elements with the repair and operational modes that differs in composition and damageability of the equipment, as well as under conditions of the development of accidents due to failure of operation of devices of relay protection and automation.

Investment in Electricity Generation and Transmission: Decision Making Under Uncertainty

DEFF Research Database (Denmark)

Conejo, Antonio J.; Baringo, Luis; Kazempour, Jalal

This book provides an in-depth analysis of investment problems pertaining to electric energy infrastructure, including both generation and transmission facilities. The analysis encompasses decision-making tools for expansion planning, reinforcement, and the selection and timing of investment...... undergraduate and graduate students in the fields of electric energy systems, operations research, management science, and economics. Practitioners in the electric energy sector will also benefit from the concepts and techniques presented here....

Making Connections for Themselves and Their Students: Examining Teachers' Organization of World History

Science.gov (United States)

Harris, Lauren McArthur

2014-01-01

The ability to make connections is an important aspect of teaching history and a vital skill in our increasingly globalized world. This study examines how preservice and practicing teachers organize and connect world historical events and concepts for themselves and for instructional purposes. Findings are based on interviews with 2 card-sorting…

Development of an economical model to determine an appropriate feed-in tariff for grid-connected solar PV electricity in all states of Australia

International Nuclear Information System (INIS)

Zahedi, A.

2009-01-01

Australia is a country with a vast amount of natural resources including sun and wind. Australia lies between latitude of 10-45 S and longitude of 112-152 E, with a daily solar exposure of between less than 3 MJ/(m 2 day) in winter and more than 30 MJ/(m 2 day) in summer. Global solar radiation in Australia varies between minimum of 3285 MJ/(m 2 year) in Hobart to 8760 MJ/(m 2 year) in Northern Territory. As a result of this wide range of radiation level there will be a big difference between costs of solar PV electricity in different locations. A study we have recently conducted on the solar PV electricity price in all states of Australia. For this purpose we have developed an economical model and a computer simulation to determine the accurate unit price of grid-connected roof-top solar photovoltaic (PV) electricity in A$/kWh for all state of Australia. The benefit of this computer simulation is that we can accurately determine the most appropriate feed-in tariff of grid-connected solar PV energy system. The main objective of this paper is to present the results of this study. A further objective of this paper is to present the details of the unit price of solar PV electricity in the state of Victoria in each month and then to compare with electricity price from conventional power systems, which is currently applied to this state. The state Victoria is located south of Australia and in terms of sun radiation is second lowest compared with the other Australian states. The computer simulation developed for this study makes it possible to determine the cost of grid-connected solar PV electricity at any location in any country based on availability of average daily solar exposure of each month as well as economical factors of the country. (author)

Phase Balancing by Means of Electric Vehicles Single-Phase Connection Shifting in a Low Voltage Danish Grid

DEFF Research Database (Denmark)

Lico, Pasqualino; Marinelli, Mattia; Knezovic, Katarina

2015-01-01

In Denmark, household consumers are supplied with three phase with neutral cable. In addition, the distribution service operator cannot decide to which phase electrical appliance are connected. The technician who realizes the installation connects the loads according to his technical expertise...

Considerations of coil protection and electrical connection schemes in large superconducting toroidal magnet system

International Nuclear Information System (INIS)

Yeh, H.T.

1976-03-01

A preliminary comparison of several different coil protection and electrical connection schemes for large superconducting toroidal magnet systems (STMS) is carried out. The tentative recommendation is to rely on external dump resistors for coil protection and to connect the coils in the toroidal magnet in several parallel loops (e.g., every fourth coil is connected into a single series loop). For the fault condition when a single coil quenches, the quenched coil should be isolated from its loop by switching devices. The magnet, as a whole, should probably be discharged if more than a few coils have quenched

Impacts of High Variable Renewable Energy Futures on Wholesale Electricity Prices, and on Electric-Sector Decision Making

OpenAIRE

Seel, J; Mills, AD; Wiser, RH

2018-01-01

Increasing penetrations of variable renewable energy (VRE) can affect wholesale electricity price patterns and make them meaningfully different from past, traditional price patterns. Many long-lasting decisions for supply- and demand-side electricity infrastructure and programs are based on historical observations or assume a business-as-usual future with low shares of VRE. Our motivating question is whether certain electric-sector decisions that are made based on assumptions reflecting low V...

Interpreting the Images in a Picture Book: Students Make Connections to Themselves, Their Lives and Experiences

Science.gov (United States)

Mantei, Jessica; Kervin, Lisa

2014-01-01

Picture books are an important and accessible form of visual art for children because they offer, among other things, opportunities for making connections to personal experiences and to the values and beliefs of families and communities. This paper reports on the use of a picture book to promote Year 4 students' making of text-to-self connections,…

Research on comprehensive decision-making of PV power station connecting system

Science.gov (United States)

Zhou, Erxiong; Xin, Chaoshan; Ma, Botao; Cheng, Kai

2018-04-01

In allusion to the incomplete indexes system and not making decision on the subjectivity and objectivity of PV power station connecting system, based on the combination of improved Analytic Hierarchy Process (AHP), Criteria Importance Through Intercriteria Correlation (CRITIC) as well as grey correlation degree analysis (GCDA) is comprehensively proposed to select the appropriate system connecting scheme of PV power station. Firstly, indexes of PV power station connecting system are divided the recursion order hierarchy and calculated subjective weight by the improved AHP. Then, CRITIC is adopted to determine the objective weight of each index through the comparison intensity and conflict between indexes. The last the improved GCDA is applied to screen the optimal scheme, so as to, from the subjective and objective angle, select the connecting system. Comprehensive decision of Xinjiang PV power station is conducted and reasonable analysis results are attained. The research results might provide scientific basis for investment decision.

On the correlation of electricity spot market prices and photovoltaic electricity generation

International Nuclear Information System (INIS)

Meyer, Tim; Luther, Joachim

2004-01-01

Discussions about market introduction of grid connected photovoltaics (PV) and its costs usually concentrate only on the gross energy produced without taking the time dependency of electricity prices and, thus, the time dependency of the value of PV electricity into account. To make a first approximation of what the effect of the time variance of electricity cost on the value of PV electricity is, the correlation with spot market prices is analysed in this paper. PV is not dispatchable by nature, but is relatively well predictable in the range of one day, if the average of spatially dispersed systems is considered. Thus, this correlation gives a good indication for the additional value of PV electricity

On the correlation of electricity spot market prices and photovoltaic electricity generation

International Nuclear Information System (INIS)

Meyer, T.; Luther, J.

2004-01-01

Discussions about market introduction of grid connected photovoltaics (PV) and its costs usually concentrate only on the gross energy produced without taking the time dependency of electricity prices and, thus, the time dependency of the value of PV electricity into account. To make a first approximation of what the effect of the time variance of electricity cost on the value of PV electricity is, the correlation with spot market prices is analysed in this paper. PV is not dispatchable by nature, but is relatively well predictable in the range of one day, if the average of spatially dispersed systems is considered. Thus, this correlation gives a good indication for the additional value of PV electricity. (Author)

Electric vehicle system for charging and supplying electrical power

Science.gov (United States)

Su, Gui Jia

2010-06-08

A power system that provides power between an energy storage device, an external charging-source/load, an onboard electrical power generator, and a vehicle drive shaft. The power system has at least one energy storage device electrically connected across a dc bus, at least one filter capacitor leg having at least one filter capacitor electrically connected across the dc bus, at least one power inverter/converter electrically connected across the dc bus, and at least one multiphase motor/generator having stator windings electrically connected at one end to form a neutral point and electrically connected on the other end to one of the power inverter/converters. A charging-sourcing selection socket is electrically connected to the neutral points and the external charging-source/load. At least one electronics controller is electrically connected to the charging-sourcing selection socket and at least one power inverter/converter. The switch legs in each of the inverter/converters selected by the charging-source/load socket collectively function as a single switch leg. The motor/generators function as an inductor.

Connecting engineering operations to strategic management: a framework for decision making in engineering offshoring

DEFF Research Database (Denmark)

Hansen, Zaza Nadja Lee; Ahmed-Kristensen, Saeema

2012-01-01

of the organisation. The Global Decision-Making (GDM) framework described here is a decision-making framework for engineering offshoring decisions for product development activities. The framework proposes that risks in engineering offshoring can be reduced by connecting engineering operations to strategic management...

Connecting Leadership and Learning: Do Versatile Learners make Connective Leaders?

Directory of Open Access Journals (Sweden)

Jill L. Robinson

2016-03-01

Full Text Available Abstract Recent failures in leadership, suggest that creating better-quality leadership development programs is critical. In moving from theory to practice, this paper examined the relationship between learning style and leadership style which may enable us to move away from one-size-fits-all leadership development programs. Utilizing Kolb’s Experiential Learning Model and Connective Leadership theory, approximately 3600 college students were analyzed to discover whether versatility in learning styles translates into versatility in leadership styles. One group of versatile learners reported using a wider range of leadership styles suggesting that learning flexibility may transfer to leadership flexibility. Surprisingly, learners of all types reported utilizing Power and Intrinsic styles of leadership above all others. Implications for leadership development include considering individual differences when crafting leadership programs, matching learning styles to leader training, and the need to move beyond one set of leadership behaviors to increase flexibility in dealing with complex situations. Using a large sample rarely seen in management studies, this paper makes key contributions to the literature. 

Making the connections: AIDS and water.

Science.gov (United States)

Ball, Anna-Marie

2006-01-01

Acknowledging AIDS as a crosscutting development issue, a Zambian rural water supply project that provides safe accessible water to rural communities embarked on a new initiative to mainstream AIDS into the water sector. The work of providing safe water takes the predominantly male workforce away from their spouses and families, into the rural villages of Zambia's Eastern Province, for long periods of time. With an HIV prevalence rate of 16.1%, the risk of HIV exposure exists for both employees and rural villagers. AIDS mainstreaming activities were designed to target both groups. An AIDS mainstreaming strategy was developed by identifying components that could be influenced in the external domain (the organization's usual work) and the internal domain (the workplace). Basic questions were addressed such as: how does AIDS affect the organization, how might the usual work aggravate susceptibility to HIV infection, and where is the comparative advantage? A workplace program including peer education, employee health education (including condoms) and a workplace policy was established for employees. For the target population, a series of five messages connecting safe water and AIDS was developed and disseminated through educational drama, community meetings and trainings, and integrated into the regular water, sanitation and hygiene activities. As an efficient utilization of resources that makes a broad impact, AIDS mainstreaming does not change the sector's mandate but takes advantage of the extensive geographic coverage and natural distribution system of water projects to disseminate AIDS information and make linkages with AIDS partners.

Understanding the effect of pulsed electric fields on thermostability of connective tissue isolated from beef pectoralis muscle using a model system.

Science.gov (United States)

Alahakoon, A U; Oey, I; Silcock, P; Bremer, P

2017-10-01

Brisket is a low value/tough meat cut that contains a large amount of connective tissue. Conversion of collagen into gelatin during heating reduces the toughness of the connective tissue however this conversion is slow at low cooking temperatures (around 60°C). The objective of this project was to determine the ability of pulsed electric field (PEF) processing to reduce the thermal stability of connective tissue. To achieve this, a novel model system was designed in which connective tissue obtained from beef deep pectotalis muscle (brisket) was exposed to PEF at combinations of electric field strength (1.0 and 1.5kV/cm) and specific energy (50 and 100kJ/kg) within an agar matrix at electrical conductivities representing the electrical conductivity found in brisket. Differential scanning calorimetry showed that PEF treatment significantly (pconnective tissue compared to untreated samples. Increasing electric field strength and the specific energy increased the Ringer soluble collagen fraction. PEF treated samples showed higher solubilization compared to the untreated samples at both 60°C and 70°C in heat solubility test. SEM examination of PEF treated (at 1.5kV/cm and 100kJ/kg) and untreated samples revealed that PEF appeared to increase the porosity of the connective tissue structure. These finding suggest that PEF processing is a technology that could be used to improve the tenderness and decrease the cooking time of collagen rich, meat cuts. Copyright © 2017 Elsevier Ltd. All rights reserved.

The role of phosphate conversion coatings in make-up of casing connections

NARCIS (Netherlands)

Ernens, D; van Riet, E.J.; de Rooij, M.B.; Pasaribu, H.R.; van Haaften, W.M.; Schipper, D.J.

2017-01-01

Phosphate conversion coatings are widely used on (premium) casing connections for protection against corrosion. Next to that, in conjunction with the lubricant these coatings provide galling protection. The friction and wear that occurs during make-up and subsequent load cycling determines the

A Novel Series Connected Batteries State of High Voltage Safety Monitor System for Electric Vehicle Application

Directory of Open Access Journals (Sweden)

Qiang Jiaxi

2013-01-01

Full Text Available Batteries, as the main or assistant power source of EV (Electric Vehicle, are usually connected in series with high voltage to improve the drivability and energy efficiency. Today, more and more batteries are connected in series with high voltage, if there is any fault in high voltage system (HVS, the consequence is serious and dangerous. Therefore, it is necessary to monitor the electric parameters of HVS to ensure the high voltage safety and protect personal safety. In this study, a high voltage safety monitor system is developed to solve this critical issue. Four key electric parameters including precharge, contact resistance, insulation resistance, and remaining capacity are monitored and analyzed based on the equivalent models presented in this study. The high voltage safety controller which integrates the equivalent models and control strategy is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated, and the online electric parameters monitor strategy is analyzed and discussed. The test results indicate that the high voltage safety monitor system designed in this paper is suitable for EV application.

A novel series connected batteries state of high voltage safety monitor system for electric vehicle application.

Science.gov (United States)

Jiaxi, Qiang; Lin, Yang; Jianhui, He; Qisheng, Zhou

2013-01-01

Batteries, as the main or assistant power source of EV (Electric Vehicle), are usually connected in series with high voltage to improve the drivability and energy efficiency. Today, more and more batteries are connected in series with high voltage, if there is any fault in high voltage system (HVS), the consequence is serious and dangerous. Therefore, it is necessary to monitor the electric parameters of HVS to ensure the high voltage safety and protect personal safety. In this study, a high voltage safety monitor system is developed to solve this critical issue. Four key electric parameters including precharge, contact resistance, insulation resistance, and remaining capacity are monitored and analyzed based on the equivalent models presented in this study. The high voltage safety controller which integrates the equivalent models and control strategy is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated, and the online electric parameters monitor strategy is analyzed and discussed. The test results indicate that the high voltage safety monitor system designed in this paper is suitable for EV application.

Topical problems connected with the German act on electricity from renewable energy sources (StrEG)

International Nuclear Information System (INIS)

Pohlmann, M.

1998-01-01

The German act (StrEG) intended to enhance the use of renewable energy sources for electricity generation and to promote the relevant technologies raises some problems in connection with constitutional law that still await judicial review by the German Federal Constitutional Court. In addition, doubts as to the lawfulness of provisions of the act have been emerging in connection with EC laws governing the regime of subsidies and state aid. The article here summarizes the current situation. (orig./CB) [de

Implications of Informal Education Experiences for Mathematics Teachers' Ability to Make Connections beyond Formal Classroom

Science.gov (United States)

Popovic, Gorjana; Lederman, Judith S.

2015-01-01

The Common Core Standard for Mathematical Practice 4: Model with Mathematics specifies that mathematically proficient students are able to make connections between school mathematics and its applications to solving real-world problems. Hence, mathematics teachers are expected to incorporate connections between mathematical concepts they teach and…

Hierarchical Load Tracking Control of a Grid-connected Solid Oxide Fuel Cell for Maximum Electrical Efficiency Operation

DEFF Research Database (Denmark)

Li, Yonghui; Wu, Qiuwei; Zhu, Haiyu

2015-01-01

efficiency operation obtained at different active power output levels, a hierarchical load tracking control scheme for the grid-connected SOFC was proposed to realize the maximum electrical efficiency operation with the stack temperature bounded. The hierarchical control scheme consists of a fast active...... power control and a slower stack temperature control. The active power control was developed by using a decentralized control method. The efficiency of the proposed hierarchical control scheme was demonstrated by case studies using the benchmark SOFC dynamic model......Based on the benchmark solid oxide fuel cell (SOFC) dynamic model for power system studies and the analysis of the SOFC operating conditions, the nonlinear programming (NLP) optimization method was used to determine the maximum electrical efficiency of the grid-connected SOFC subject...

Informatics Solutions for Prosumers connected to Smart Grids

Directory of Open Access Journals (Sweden)

Simona Vasilica OPREA

2015-03-01

Full Text Available This paper gives a brief overview about electricity consumption optimization based on consumption profiles of electricity prosumers that are connected to smart grids. The main object of this approach is identification of informatics solutions for electricity consumption optimization in order to decrease electricity bill. In this way, larger scale integration of renewable energy sources is allowed therefore entire society will gain benefits. This paper describes the main objectives of such informatics system and stages for its implementation. The system will analyze the specific profile and behavior of each electricity consumer or prosumer, automatically assist him to make right decisions and offer optimal advice for usage of controllable and non-controllable appliances. It will serve, based on big data transfer from electricity consumers or prosumers, as a powerful tool for grid operators that will be able to better plan their resources.

Azure Dynamics transit connect : EV2010VE : upfitting to a battery electric vehicle

Energy Technology Data Exchange (ETDEWEB)

Oldham, B. [Azure Dynamics Corp., Toronto, ON (Canada)

2010-07-01

Transit Connect is a delivery vehicle brought to North America in 2010 that was initially released in Europe as part of Ford's global platform program. The stock layout includes the front engine; front wheel drive; fuel tank in rear; gasoline in North America; and diesel in Europe. This presentation described what Azure Dynamics Corporation did to improve the engine, transmission, energy storage, power steering, air conditioning, and generator. An overview of Transit Connect was provided. The presentation discussed design consideration, with particular reference to crash worthiness; durability; and total cost of implementation. Electrical harness and the total cost of implementation were also addressed. Other topics that were presented included the glider based design; a glider based design commonized platform; and additional design features. tabs., figs.

A novel scheme for making cheap electricity with nuclear energy

International Nuclear Information System (INIS)

Pettibone, J.S.

1991-04-01

Nuclear fuels should produce cheaper electricity than coal, considering their high specific energy and low cost. To exploit these properties, the scheme proposed here replaces the expensive reactor/steam-turbine system with an engine in which the expansion of a gas heated by a nuclear explosion raises a mass of liquid, thereby producing stored hydraulic energy. This energy could be converted to electricity by hydroelectric generation with water as the working fluid or by magnetohydrodynamic (MHD) generation with molten metal. A rough cost analysis suggests the hydroelectric system could reduce the present cost of electricity by two-thirds, and the MHD system by even more. Such cheap power would make feasible large-scale electrolysis to produce hydrogen and other fuels and chemical raw materials. 2 refs., 1 fig

Economic evaluation of photovoltaic electric power generation connected to the grid in deregulated electric power markets; Avaliacao economica da geracao de energia eletrica fotovoltaica conectada a rede em mercados eletricos desregulados

Energy Technology Data Exchange (ETDEWEB)

Zumaran, David Richard Orosco

2000-12-01

This work presents an analysis of economic, tariff and regulating issues related to the introduction of Grid Connected Photovoltaic Systems in a deregulated electric market context; a case study for the peruvian electric market is realized. Based on the pricing system of the electric market, it is developed an economic assessment model that can be used by institutions interested in promoting this technology for generating electricity. (author)

Hierarchical Load Tracking Control of a Grid-Connected Solid Oxide Fuel Cell for Maximum Electrical Efficiency Operation

Directory of Open Access Journals (Sweden)

Yonghui Li

2015-03-01

Full Text Available Based on the benchmark solid oxide fuel cell (SOFC dynamic model for power system studies and the analysis of the SOFC operating conditions, the nonlinear programming (NLP optimization method was used to determine the maximum electrical efficiency of the grid-connected SOFC subject to the constraints of fuel utilization factor, stack temperature and output active power. The optimal operating conditions of the grid-connected SOFC were obtained by solving the NLP problem considering the power consumed by the air compressor. With the optimal operating conditions of the SOFC for the maximum efficiency operation obtained at different active power output levels, a hierarchical load tracking control scheme for the grid-connected SOFC was proposed to realize the maximum electrical efficiency operation with the stack temperature bounded. The hierarchical control scheme consists of a fast active power control and a slower stack temperature control. The active power control was developed by using a decentralized control method. The efficiency of the proposed hierarchical control scheme was demonstrated by case studies using the benchmark SOFC dynamic model.

Possible use of electric cars as balancing instrument

Energy Technology Data Exchange (ETDEWEB)

Tirez, Andreas; Luickx, Patrick; Woitrin, Dominique

2010-09-15

A massive introduction of electric cars is foreseeable in the mid to long term. Implementing a 'vehicle-to-grid' setting makes it possible to use these cars to deliver ancillary services to the electricity system. In this paper, the possibility of delivering active reserves in the Belgian control area is analyzed. We assume one million electric cars that can be connected to the Belgian grid. Based on our simulation, electric cars could be used for delivering all primary, all secondary and part of the tertiary reserves. Using electric cars as a balancing instrument would facilitate absorbing intermittent energy into the electricity system.

Are small-scale grid-connected photovoltaic systems a cost-effective policy for lowering electricity bills and reducing carbon emissions? A technical, economic, and carbon emission analysis

International Nuclear Information System (INIS)

McHenry, Mark P.

2012-01-01

This research discusses findings from technical simulations and economic models of 1 kW p and 3 kW p grid-connected photovoltaic (PV) systems supplying a rural home electricity load in parallel with the electricity network in Western Australia (WA). The technical simulations are based on electricity billing, consumption monitoring, an energy audit data, combined with 15 min interval load and PV system performance for commercially available technologies and balance of system components, using long-term meteorological input data. The economic modelling uses 2010 market prices for capital costs, operational costs, electricity tariffs, subsidies, and is based on discounted cash flow analyses which generate a final net present value (NPV) for each system against network electricity costs (in Australian dollars, AUD) over a 15 year investment horizon. The results suggest that current market prices generate a negative NPV (a net private loss), even with the current government subsidies, which lead to higher home electricity costs than conventional network electricity use. Additionally, the private costs of carbon emission mitigation (AUD tCO 2 -e −1 ) for the grid-connected PV system simulations and models were around AUD 600-700 tCO 2 -e −1 , a particularly expensive option when compared to existing large-scale renewable energy mitigation activities. - Highlights: ► Subsidised small-scale grid-connected PV systems can increase home electricity costs. ► Subsidies for private PV systems are provided by those who do not receive a benefit. ► Small-scale grid-connected PV systems result in very high costs of mitigation. ► Verifying actual mitigation from grid-connected small-scale systems is problematic. ► Maintain medium/large-scale grid-connected or small-scale off-grid system subsidies.

Profitability analysis of grid-connected photovoltaic facilities for household electricity self-sufficiency

International Nuclear Information System (INIS)

Colmenar-Santos, Antonio; Campíñez-Romero, Severo; Pérez-Molina, Clara; Castro-Gil, Manuel

2012-01-01

Spain exhibits a high level of energy dependence and has significant solar energy resources. These two facts have given rise to the prominence that renewable energy, particularly solar photovoltaic technology, has enjoyed in recent years, supported by a favorable regulatory framework. Currently, the Spanish Government is providing new ways in energy policy to enhance and accelerate the development of low-power photovoltaic generation facilities for self-consumption by introducing energy policies for feed-in payments of surplus electricity. Such facilities are an example of distributed electrical generation with important benefits for the environment and the rest of the electrical system because, when properly managed, they can help improve the system’s stability and reduce overall losses. By analyzing household demand and solar photovoltaic energy resources, the profitability of such facilities is considered in this article, taking into account the technical and economic impact of storage systems and proposing models for feed-in payments of surplus electricity, in an attempt to assess whether this method of electricity generation versus the method of conventionally supplied power from a grid at a regulated tariff can rival each other economically, in terms of parity. - Highlight: ► The use of grid-connected photovoltaic facilities for household electricity self-sufficiency is presented. ► The need for legal frameworks that include retributive mechanisms for the surplus energy is pointed out. ► Two models are proposed for the remuneration of surplus energy generated. ► Models show economic profitability without feed-in-tariff or compensations. ► Facilities described offer ancillary services for grid stability and smart-grid integration.

Enhanced electricity system analysis for decision making - A reference book

International Nuclear Information System (INIS)

2000-01-01

The objective of electricity system analysis in support of decision making is to provide comparative assessment results upon which relevant policy choices between alternative technology options and supply strategies can be based. This reference book offers analysts, planners and decision makers documented information on enhanced approaches to electricity system analysis, that can assist in achieving this objective. The book describes the main elements of comprehensive electricity system analysis and outlines an advanced integrated analysis and decision making framework for the electric power sector. Emphasis is placed on mechanisms for building consensus between interested and affected parties, and on aspects of planning that go beyond the traditional economic optimisation approach. The scope and contents of the book cover the topics to be addressed in decision making for the power sector and the process of integrating economic, social, health and environmental aspects in the comparative assessment of alternative options and strategies. The book describes and discusses overall frameworks, processes and state of the art methods and techniques available to analysts and planners for carrying out comparative assessment studies, in order to provide sound information to decision makers. This reference book is published as part of a series of technical reports and documents prepared in the framework of the inter-agency joint project (DECADES) on databases and methodologies for comparative assessment of different energy sources for electricity generation. The overall objective of the DECADES project is to enhance capabilities for incorporating economic, social, health and environmental issues in the comparative assessment of electricity generation options and strategies in the process of decision making for the power sector. The project, established in 1992, is carried out jointly by the European Commission (EC), the Economic and Social Commission for Asia and the Pacific

The history of re-connection and the concept of the solar wind plasma with relatively small electrical conductivity

Science.gov (United States)

Chertkov, A. D.

1995-01-01

Petschek's 're-connection' model, aspiring to be universal, treated as a boundary problem meets unresolvable difficulties connected with impossibility to specify correctly boundary and initial conditions. This problem was incorrectly formulated. Hence, ineradicable logarithmic singularities occurred on the boundary surfaces. Attempts to eliminate them by incorporating the finite electrical conductivity are incorrect. This should lead to the change in the equation type, boundary condition type and in consequence to the change in solutions. Besides, the slow mode shocks cannot be driven by small internal source. As an alternative a new plasma concept is suggested. The state of fully ionized plasma in space depends completely on the entropy of the plasma heating source and on the process in which plasma is involved. The presumptive source of the solar wind creation - the induction electric field of the solar origin - has very low entropy. The state of plasma should be very far from the thermodynamic equilibrium. Debye's screening is not complete. The excitation of the powerful resonant self-consistent electric fields in plasma provides low electric conductivity. The MHD problems should be treated in frameworks of dissipative theories.

Prophylactic and thermovision measurements of electric machines and equipment

Energy Technology Data Exchange (ETDEWEB)

Jedlicka, R; Brestovansky, L [Atomova Elektraren Bohunice, Jaslovske Bohunice (Slovakia)

1997-12-31

High-voltage measurements of generators, unit and service transformers and some significant motor drives used at a nuclear power plant are described in this paper. Thermovision measurements of electric machines and distribution systems are dealt with in the second part of the paper. Power electric equipment represent one of the most significant components of a nuclear power plant. Turbine mechanical energy is converted into the electrical energy within these equipment. Power generated by generators is transformed by transformers so that it can achieve appropriate parameters for both the transmission over the distribution system and the power plant service power supply. The service power supply switchboards and cables provide supply to motors and other consumers necessary for the nuclear power plant technological process. The whole complex of equipment has to be maintained in good technical conditions. It is necessary to make thermovision and prophylactic measurements to identify and verify the electric equipment technical condition. The mentioned measurements warn the operation staff in advance against both gradual deterioration of power connection contact resistances, i.e. power connections overheating, and the machine insulation systems condition deterioration. The operation staff try to prevent the electric equipment operation accidents by early removing the detected failures, thus, improving the nuclear safety. In order to provide the above-mentioned activities a special prophylactic measurement group was established at the NPP Bohunice in 1983. The group specialists make following types of measurements. 1. Prophylactic measurements of electric machines. Prophylactics of 220 MW generators and 6 MW service power generators; Prophylactics of both unit and service transformers and VHV bushings; Prophylactics of major 6 kV motor drives. 2. Thermovision measurements of current connections. (Abstract Truncated)

Prophylactic and thermovision measurements of electric machines and equipment

International Nuclear Information System (INIS)

Jedlicka, R.; Brestovansky, L.

1996-01-01

High-voltage measurements of generators, unit and service transformers and some significant motor drives used at a nuclear power plant are described in this paper. Thermovision measurements of electric machines and distribution systems are dealt with in the second part of the paper. Power electric equipment represent one of the most significant components of a nuclear power plant. Turbine mechanical energy is converted into the electrical energy within these equipment. Power generated by generators is transformed by transformers so that it can achieve appropriate parameters for both the transmission over the distribution system and the power plant service power supply. The service power supply switchboards and cables provide supply to motors and other consumers necessary for the nuclear power plant technological process. The whole complex of equipment has to be maintained in good technical conditions. It is necessary to make thermovision and prophylactic measurements to identify and verify the electric equipment technical condition. The mentioned measurements warn the operation staff in advance against both gradual deterioration of power connection contact resistances, i.e. power connections overheating, and the machine insulation systems condition deterioration. The operation staff try to prevent the electric equipment operation accidents by early removing the detected failures, thus, improving the nuclear safety. In order to provide the above-mentioned activities a special prophylactic measurement group was established at the NPP Bohunice in 1983. The group specialists make following types of measurements. 1. Prophylactic measurements of electric machines. Prophylactics of 220 MW generators and 6 MW service power generators; Prophylactics of both unit and service transformers and VHV bushings; Prophylactics of major 6 kV motor drives. 2. Thermovision measurements of current connections. Measurements enumarated in paragraph 1 are made on disconnected electric

Impact of electric vehicles in the steady state operation of distribution systems

OpenAIRE

Erasmo Saraiva de Castro

2015-01-01

This work aims to quantify the impact in the steady state operation of a distribution system when electric vehicles are connected. It is worth noting that the connection of them may cause significant changes in the voltage profile, in the degree of voltage unbalance and in the electrical losses of the system. In order to make this analysis, a three-phase power flow program was developed in MATLAB language. This program is based on the Ladder Iterative Technique and it contains models of overh...

Webinar: Making the Connection: Linking IAQ, Energy Efficiency and Preventive Maintenance Together for Healthy Schools

Science.gov (United States)

A page to register to view the February 22, 2018, Energy Savings Plus Health for Schools Webinar Series Webinar: Making the Connection: Linking IAQ, Energy Efficiency and Preventive Maintenance Together for Healthy Schools

IEEE standard for type test of class 1E electric cables, field splices, and connections for nuclear power generating stations

International Nuclear Information System (INIS)

Anon.

1974-01-01

The Institute of Electrical and Electronics Engineers has generated this document to provide guidance for developing a program to type test cables, field splices, and connections and obtain specific type test data. It supplements IEEE Std 323-1974 Standard for Qualifying Class IE Equipment for Nuclear Power Generating Stations, which describes basic requirements for equipment qualification. It is the integrated performance of the structures, fluid systems, the electrical systems, the instrumentation systems of the station, and in particular, the plant protection system, that limits the consequences of accidents. Seismic effects on installed cable systems are not within the scope of this document. Section 2 of this guide is an example of type tests. It is the purpose of this guide to deal with cable and connections; however, at the time of issue, detailed examples of tests for connections were not available

Towards a single European electricity market. A structured approach to regulatory mode decision-making

International Nuclear Information System (INIS)

De Jong, H.M.

2009-01-01

This study focuses on the processes through which the rules and regulations that govern European electricity markets - and inherently, their integration process - are established. So far, European policy makers have largely followed a 'trial-and-error' approach to finding an appropriate regulatory mode (process) for dealing effectively with market integration issues. This unstructured approach to regulatory mode selection leads to several problems: - Today's trial-and-error strategy of shifting from one regulatory mode to another is time-consuming. - In the regulatory mode selection process, certain key principles of good governance are insufficiently considered. - European regulatory processes are experienced as vague, intransparent, and illegitimate by 'outside' stakeholders. This study develops a 'structured approach to regulatory mode decision-making' (STARMODE) based on the theory of decision modelling in policy management and a case study exploring three key market integration issues in the field of electricity markets: interconnector investment, congestion management and market transparency. The main objective is to present a systematic and comprehensive framework for analysing and improving regulatory mode decision-making in the context of the European Union, focusing on electricity market integration. The STARMODE approach is generally applicable to (and relevant for) European market integration issues in industries characterized by a natural monopoly and/or an essential service. The approach may also contribute to national regulatory mode decision-making and multi-state decision-making in other continents.

Influence of the oscillating electric field on the photodetachment of H− ion in a static electric field

International Nuclear Information System (INIS)

Wang, De-hua

2017-01-01

Highlights: • The photodetachment of H − in an oscillating electric field has been studied using the time-dependent closed orbit theory. • An analytical formula for calculating the photodetachement cross section has been put forward. • Our study provides a clear physical picture for the photodetachment of negative ion in an oscillating electric filed. • Our work is useful in guiding the experimental research for the photodetachment dynamics in the time-dependent field. - Abstract: Using the time-dependent closed orbit theory, we study the photodetachment of H − ion in a time-dependent electric field. The photodetachment cross section is specifically studied in the presence of a static electric field plus an oscillating electric field. We find that the photodetachment of negative ion in the time-dependent electric field becomes much more complicated than the case in a static electric field. The oscillating electric field can weaken the photodetachment cross section greatly when the strength of the oscillating electric field is less than the static electric field. However, as the strength of the oscillating electric field is larger than the static electric field, four types of closed orbits are identified for the detached electron, which makes the oscillating amplitude in the photodetachment cross section gets increased again. The connection between the detached electron’s closed orbit with the oscillating cross section is analyzed quantitatively. This study provides a clear and intuitive picture for the understanding of the connections between quantum and classical description for the time-dependent Hamiltonian systems and may guide the future experimental research for the photodetachment dynamics in the time-dependent electric field.

An integrated DEA-COLS-SFA algorithm for optimization and policy making of electricity distribution units

International Nuclear Information System (INIS)

Azadeh, A.; Ghaderi, S.F.; Omrani, H.; Eivazy, H.

2009-01-01

This paper presents an integrated data envelopment analysis (DEA)-corrected ordinary least squares (COLS)-stochastic frontier analysis (SFA)-principal component analysis (PCA)-numerical taxonomy (NT) algorithm for performance assessment, optimization and policy making of electricity distribution units. Previous studies have generally used input-output DEA models for benchmarking and evaluation of electricity distribution units. However, this study proposes an integrated flexible approach to measure the rank and choose the best version of the DEA method for optimization and policy making purposes. It covers both static and dynamic aspects of information environment due to involvement of SFA which is finally compared with the best DEA model through the Spearman correlation technique. The integrated approach would yield in improved ranking and optimization of electricity distribution systems. To illustrate the usability and reliability of the proposed algorithm, 38 electricity distribution units in Iran have been considered, ranked and optimized by the proposed algorithm of this study.

Operating and impact of the compensation mechanism of the electric utility charges on the energy offer in non connected areas

International Nuclear Information System (INIS)

Levratto, N.

2005-01-01

Since the law of the 10 february 2000 relative to the modernization and the development of the electric utility, the France adopted a mechanism aiming to compensate the costs subjected by EDF and other suppliers providing a public utility mission in the domain of the electricity production and distribution. This document takes stock on the organization, the evaluation and the economical and environmental consequences of the implementing of a compensation system of costs bond to the electricity production in non connected areas. (A.L.B.)

Insulated Solar Electric Cooking – Tomorrow's healthy affordable stoves?

Directory of Open Access Journals (Sweden)

T. Watkins

Full Text Available We present a cooking technology consisting of a solar panel directly connected to an electric heater inside of a well-insulated chamber. Assuming continued decrease in solar panel prices, we anticipate that in a few decades Solar Electric Cooking (SEC technologies will be the most common cooking technology for the poor. Appropriate use of insulation reduces the power demand making low-power Insulated Solar Electric Cooking (ISEC systems already cost competitive. We present a $100 prototype and preliminary results of two implementations in Uganda.

Order of the 23 March 2006 relative to the return rate on the immobilized capital for the electric power production installation in non connected areas

International Nuclear Information System (INIS)

2006-04-01

This order fixes the return rate on the investments capital of electric power production in non connected areas, used for the calculation of the compensation expenses of the electric utilities. (A.L.B.)

Type test of Class 1E electric cables, field splices, and connections for nuclear power generating stations - 1975

International Nuclear Information System (INIS)

Anon.

1976-01-01

This Standard provides direction for establishing type tests which may be used in qualifying Class 1E electric cables, field splices, and other connections for service in nuclear power generating stations. General guidelines for qualifications are given in IEEE Std 323-1974, Standard for Qualifying Class 1E Electric Equipment for Nuclear Power Generating Stations. Categories of cables covered are those used for power control and instrumentation services. Though intended primarily to pertain to cable for field installation, this guide may also be used for the qualification of internal wiring of manufactured devices

Impacts of High Variable Renewable Energy Futures on Wholesale Electricity Prices, and on Electric-Sector Decision Making

Energy Technology Data Exchange (ETDEWEB)

Seel, Joachim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wiser, Ryan H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Deb, Sidart [LCG Consulting, Los Altos, CA (United States); Asokkumar, Aarthi [LCG Consulting, Los Altos, CA (United States); Hassanzadeh, Mohammad [LCG Consulting, Los Altos, CA (United States); Aarabali, Amirsaman [LCG Consulting, Los Altos, CA (United States)

2018-05-11

Increasing penetrations of variable renewable energy (VRE) can affect wholesale electricity price patterns and make them meaningfully different from past, traditional price patterns. Many long-lasting decisions for supply- and demand-side electricity infrastructure and programs are based on historical observations or assume a business-as-usual future with low shares of VRE. Our motivating question is whether certain electric-sector decisions that are made based on assumptions reflecting low VRE levels will still achieve their intended objective in a high VRE future. We qualitatively describe how various decisions may change with higher shares of VRE and outline an analytical framework for quantitatively evaluating the impacts of VRE on long-lasting decisions. We then present results from detailed electricity market simulations with capacity expansion and unit commitment models for multiple regions of the U.S. for low and high VRE futures. We find a general decrease in average annual hourly wholesale energy prices with more VRE penetration, increased price volatility and frequency of very low-priced hours, and changing diurnal price patterns. Ancillary service prices rise substantially and peak net-load hours with high capacity value are shifted increasingly into the evening, particularly for high solar futures. While in this report we only highlight qualitatively the possible impact of these altered price patterns on other demand- and supply-side electric sector decisions, the core set of electricity market prices derived here provides a foundation for later planned quantitative evaluations of these decisions in low and high VRE futures.

Stacking multiple connecting functional materials in tandem organic light-emitting diodes

Science.gov (United States)

Zhang, Tao; Wang, Deng-Ke; Jiang, Nan; Lu, Zheng-Hong

2017-02-01

Tandem device is an important architecture in fabricating high performance organic light-emitting diodes and organic photovoltaic cells. The key element in making a high performance tandem device is the connecting materials stack, which plays an important role in electric field distribution, charge generation and charge injection. For a tandem organic light-emitting diode (OLED) with a simple Liq/Al/MoO3 stack, we discovered that there is a significant current lateral spreading causing light emission over an extremely large area outside the OLED pixel when the Al thickness exceeds 2 nm. This spread light emission, caused by an inductive electric field over one of the device unit, limits one’s ability to fabricate high performance tandem devices. To resolve this issue, a new connecting materials stack with a C60 fullerene buffer layer is reported. This new structure permits optimization of the Al metal layer in the connecting stack and thus enables us to fabricate an efficient tandem OLED having a high 155.6 cd/A current efficiency and a low roll-off (or droop) in current efficiency.

Cheap electricity with autonomous solar cell systems

International Nuclear Information System (INIS)

Ouwens, C.D.

1993-01-01

A comparison has been made between the costs of an autonomous solar cell system and a centralized electricity supply system. In both cases investment costs are the main issue. It is shown that for households in densely populated sunny areas, the use of autonomous solar cell systems is - even with today's market prices - only as expensive or even cheaper than a grid connection, as long as efficient electric appliances are used. The modular nature of solar cell systems makes it possible to start with any number of appliances, depending on the amount of money available to be spent. (author)

Grid-connected vehicles as the core of future land-based transport systems

International Nuclear Information System (INIS)

Gilbert, Richard; Perl, Anthony

2007-01-01

Grid-connected vehicles (GCVs)-e.g., electric trains, metros, trams, and trolley buses-are propelled by electric motors directly connected to remote power sources. Their low at-vehicle energy consumption and ability to use a wide range of renewable energy sources make them strong contenders for urban and interurban transport systems in an era of energy constraints that favours use of renewable fuels, which may lie ahead. Needs for autonomous motorised mobility could be acceptably met in large measure by deployment of personal GCVs, also known as personal rapid transit (PRT). Alternatives, including fuel-cell vehicles and dual-drive vehicles fuelled with ethanol, will be less feasible. The 'car of the future' may not be an automobile so much as a PRT element of a comprehensive GCV-based system that offers at least as much utility and convenience as today's transport systems

Is climate change-centrism an optimal policy making strategy to set national electricity mixes?

International Nuclear Information System (INIS)

Vázquez-Rowe, Ian; Reyna, Janet L.; García-Torres, Samy; Kahhat, Ramzy

2015-01-01

Highlights: • The impact of climate-centric policies on other environmental impacts is uncertain. • Analysis of changing electricity grids of Peru and Spain in the period 1989–2013. • Life Cycle Assessment was the selected sustainability method to conduct the study. • Policies targeting GHG reductions also reduce air pollution and toxicity. • Resource usage, especially water, does not show the same trends as GHG emissions. - Abstract: In order to combat the threat of climate change, countries have begun to implement policies which restrict GHG emissions in the electricity sector. However, the development of national electricity mixes should also be sensitive to resource availability, geo-political forces, human health impacts, and social equity concerns. Policy focused on GHG goals could potentially lead to adverse consequences in other areas. To explore the impact of “climate-centric” policy making on long-term electricity mix changes, we develop two cases for Peru and Spain analyzing their changing electricity grids in the period 1989–2013. We perform a Life Cycle Assessment of annual electricity production to catalogue the improvements in GHG emissions relative to other environmental impacts. We conclude that policies targeting GHG reductions might have the co-benefit of also reducing air pollution and toxicity at the expense of other important environmental performance indicators such as water depletion. Moreover, as of 2013, both countries generate approximately equal GHG emissions per kWh, and relatively low emission rates of other pollutants compared to nations of similar development levels. Although climate-centric policy can lead to some positive environmental outcomes in certain areas, energy policy-making should be holistic and include other aspects of sustainability and vulnerability.

Electric vehicle data acquisition system

DEFF Research Database (Denmark)

Svendsen, Mathias; Winther-Jensen, Mads; Pedersen, Anders Bro

2014-01-01

and industrial applications, e.g. research in electric vehicle driving patterns, vehicle substitutability analysis and fleet management. The platform is based on a embedded computer running Linux, and features a high level of modularity and flexibility. The system operates independently of the make of the car......, by using the On-board Diagnostic port to identify car model and adapt its software accordingly. By utilizing on-board Global Navigation Satellite System, General Packet Radio Service, accelerometer, gyroscope and magnetometer, the system not only provides valuable data for research in the field of electric......A data acquisition system for electric vehicles is presented. The system connects to the On-board Diagnostic port of newer vehicles, and utilizes the in-vehicle sensor network, as well as auxiliary sensors, to gather data. Data is transmitted continuously to a central database for academic...

Book review: Making is connecting the social meaning of creativity, from DIY and knitting to Youtube and web 2.0

DEFF Research Database (Denmark)

Gürsimsek, Ödül

2012-01-01

Making is Connecting reframes the definition of creativity by looking into the act of crafting; the Arts and Crafts movement, hands-on making, Do-It-Yourself (DIY) and more contemporarily the culture of Web 2.0. In this book, Gauntlett reflects on Web 2.0 and off-line craft-making in order to for...

On the electrical contact and long-term behavior of compression-type connections with conventional and high-temperature conductor ropes with low sag; Zum elektrischen Kontakt- und Langzeitverhalten von Pressverbindungen mit konventionellen und Hochtemperatur-Leiterseilen mit geringem Durchhang

Energy Technology Data Exchange (ETDEWEB)

Hildmann, Christian

2016-12-09

In Germany and in Europe it is due to the ''Energiewende'' necessary to transmit more electrical energy with existing overhead transmission lines. One possible technical solution to reach this aim is the use of high temperature low sag conductors (HTLS-conductors). Compared to the common Aluminium Conductor Steel Reinforced (ACSR), HTLS-conductors have higher rated currents and rated temperatures. Thus the electrical connections for HTLS-conductors are stressed to higher temperatures too. These components are most important for the safe and reliable operation of an overhead transmission line. Besides other connection technologies, hexagonal compression connections with ordinary transmission line conductors have proven themselves since decades. From the literature, mostly empirical studies with electrical tests for compression connections are known. The electrical contact behaviour, i.e. the quality of the electrical contact after assembly, of these connections has been investigated insufficiently. This work presents and enhances an electrical model of compression connections, so that the electrical contact behaviour can be determined more accurate. Based on this, principal considerations on the current distribution in the compression connection and its influence on the connection resistance are presented. As a result from the theoretical and the experimental work, recommendations for the design of hexagonal compression connections for transmission line conductors were developed. Furthermore it is known from the functional principle of compression type connections, that the electrical contact behaviour can be influenced from their form fit, force fit and cold welding. In particular the forces in compression connections have been calculated up to now by approximation. The known analytical calculations simplify the geometry and material behaviour and do not consider the correct mechanical load during assembly. For these reasons the joining process

Identifying the Effective Factors in Making Trust in Online Social Networks on the perspective of Iranian experts Using Fuzzy ELECTRE

Directory of Open Access Journals (Sweden)

Elham Haghighi

2015-12-01

Full Text Available this paper attempts to rank the effective factors in making trust in social networks to provide the possibility of attracting and increasing users’ trust on these social networks for providers and designers of online social networks. Identifying the effective factors in making trust in social networks is a multi-criteria decision making problem and most of effective factors are ambiguous and uncertain, thereby this article uses Fuzzy ELECTRE to rank them. By implementing Fuzzy ELECTRE on gathered data, respectively «usability factor», «supporting up to date technology factor», «integrity» and «the rate of ethics factor» are on the top of effective factors in making trust in users. In general, «web features» and «technology features» have a higher degree of importance than «security features», «individual-social features» and «cultural features». Ranking of Fuzzy ELECTRE comparison ranking of Fuzzy TOPSIS and Fuzzy ELECTRE method becomes validate because Spearman correlation coefficients is 0/867. Result of sensitivity analysis on changing weight of criteria shows that Fuzzy ELECTRE isn’t affected by ambiguity and uncertainty in inputs.

Proposal for the award of a contract for the supply of connection boxes for electrical racks for the LHC magnets

CERN Document Server

2004-01-01

This document concerns the award of a contract for the supply of 1670 connection boxes for two different types of electrical racks for the LHC magnets. The Finance Committee is invited to agree to the negotiation of an ex-works contract with CRAWFORD, HANSFORD & KIMBER (GB), for the supply of 1670 connection boxes for a total amount of 473 774 pounds sterling (1 080 442 Swiss francs), not subject to revision. The rate of exchange used is that stipulated in the tender.

Techno-economic and sensitivity analysis for grid-connected renewable energy electric boat charging station in Terengganu

Directory of Open Access Journals (Sweden)

Salleh N. A. S.

2017-01-01

Full Text Available In order to encourage the eco-friendly technologies in transportation sector, the reliance on fuel need to be reduced and the use of renewable energy (RE technology as energy source are widely explored by researchers. Thus, this study focus on the feasibility of developing grid-connected renewable energy electric boat charging station for the fishermen in Terengganu using simulation-based method by HOMER software. Five year solar radiation and wind speed data were collected at Universiti Sultan Zainal Abidin (UNISZA weather station. For load profile, the information about fishing activities and the amount of subsidy spent by the government were obtained from the interview session with the fishermen and validated with Lembaga Kemajuan Ikan Malaysia (LKIM. The results acquired are compared between grid-only and grid-connected RE systems in term of net present cost (NPC, operational cost and payback period. A sensitivity analysis is done to find the minimal Feed-in Tariff (FiT rate that can be implemented in order to encourage the use of RE system in this sector. Then, the relationship between FiT and NPC, payback period and emission of pollutants are analyzed. At current FiT rates RM 0.813/kWh, hybrid grid-PV system manages to achieve its optimal in generating high income from selling the power to the grid with convincing amount of electricity production and short payback period. It is concluded at minimum RM 0.56/kWh of FiT, the grid-connected RE system is possible to be developed because its performance shows better outcome compared to the grid-only system.

Inverse Optimization and Forecasting Techniques Applied to Decision-making in Electricity Markets

DEFF Research Database (Denmark)

Saez Gallego, Javier

patterns that the load traditionally exhibited. On the other hand, this thesis is motivated by the decision-making processes of market players. In response to these challenges, this thesis provides mathematical models for decision-making under uncertainty in electricity markets. Demand-side bidding refers......This thesis deals with the development of new mathematical models that support the decision-making processes of market players. It addresses the problems of demand-side bidding, price-responsive load forecasting and reserve determination. From a methodological point of view, we investigate a novel...... approach to model the response of aggregate price-responsive load as a constrained optimization model, whose parameters are estimated from data by using inverse optimization techniques. The problems tackled in this dissertation are motivated, on one hand, by the increasing penetration of renewable energy...

Techno-economic and sensitivity analysis for grid-connected renewable energy electric boat charging station in Terengganu

OpenAIRE

Salleh N. A. S.; Muda W. M. W.

2017-01-01

In order to encourage the eco-friendly technologies in transportation sector, the reliance on fuel need to be reduced and the use of renewable energy (RE) technology as energy source are widely explored by researchers. Thus, this study focus on the feasibility of developing grid-connected renewable energy electric boat charging station for the fishermen in Terengganu using simulation-based method by HOMER software. Five year solar radiation and wind speed data were collected at Universiti Sul...

Thermo-optically tuned photonic resonators with concurrent electrical connection and thermal isolation

Science.gov (United States)

Lentine, Anthony L.; Kekatpure, Rohan Deodatta; Zortman, William A.; Savignon, Daniel J.

2016-06-14

A photonic resonator system is designed to use thermal tuning to adjust the resonant wavelength of each resonator in the system, with a separate tuning circuit associated with each resonator so that individual adjustments may be made. The common electrical ground connection between the tuning circuits is particularly formed to provide thermal isolation between adjacent resonators by including a capacitor along each return path to ground, where the presence of the capacitor's dielectric material provides the thermal isolation. The use of capacitively coupling necessarily requires the use of an AC current as an input to the heater element (conductor/resistor) of each resonator, where the RMS value of the AC signal is indicative of the amount of heat that is generated along the element and the degree of wavelength tuning that is obtained.

Neuroscience & the Classroom: Making Connections. A Video Course for Grades K-12 Teachers and School Counselors

Science.gov (United States)

Annenberg Learner, 2012

2012-01-01

Exciting developments in the field of neuroscience are leading to a new understanding of how the brain works that is beginning to transform teaching in the classroom. "Neuroscience & the Classroom: Making Connections" brings together researchers and educators in a dialog about how insights into brain function can be harnessed by teachers for use…

Design of grid connected PV systems considering electrical, economical and environmental aspects: A practical case

International Nuclear Information System (INIS)

Fernandez-Infantes, Alberto; Contreras, Javier; Bernal-Agustin, Jose L.

2006-01-01

This paper presents the complete design of a photovoltaic installation that may be either used for internal electric consumption or for sale using the premium subsidy awarded by the Spanish Government. Electric optimization strategies are detailed in the project, as well as the sizing of the photovoltaic installation and economic and financial issues related to it. The project optimizes the electricity demand, improving reactive power and studying the convenience of hourly discrimination fees in addition to the design of the photovoltaic installation. A specific computer application for the automated calculation of all relevant parameters of the installation-physical, electrical, economical as well as ecological-has been developed to make the process of calculating photovoltaic installations easier and to reduce the design development time. Moreover, the budget of the photovoltaic installation is included, as well as its corresponding financial ratios and payback periods. Finally, the conclusions reached in the technical and economic design of the installation are shown. (author)

Directly connected series coupled HTPEM fuel cell stacks to a Li-ion battery DC bus for a fuel cell electrical vehicle

DEFF Research Database (Denmark)

Andreasen, Søren Juhl; Ashworth, Leanne; Remón, Ian Natanael

2008-01-01

The work presented in this paper examines the use of pure hydrogen fuelled high temperature polymer electrolyte membrane (HTPEM) fuel cell stacks in an electrical car, charging a Li-ion battery pack. The car is equipped with two branches of two series coupled 1 kW fuel cell stacks which...... are connected directly parallel to the battery pack during operation. This enables efficient charging of the batteries for increased driving range. With no power electronics used, the fuel cell stacks follow the battery pack voltage, and charge the batteries passively. This saves the electrical and economical...... losses related to these components and their added system complexity. The new car battery pack consists of 23 Li-ion battery cells and the charging and discharging are monitored by a battery management system (BMS) which ensures safe operating conditions for the batteries. The direct connection...

Engaging Students in Traditional and Digital Storytelling to Make Connections between Pedagogy and Children's Experiences

Science.gov (United States)

Lisenbee, Peggy S.; Ford, Carol M.

2018-01-01

Traditional and digital storytelling is a powerful literacy tool which engage students in making connections between pedagogy and academic content. Definitions of traditional and digital storytelling, pedagogical methods aligned with curriculum standards, and examples of literacy centers associated with storytelling in early childhood classrooms…

Grid-connected solar electricity in France : the example of Martinique, a French overseas department

Energy Technology Data Exchange (ETDEWEB)

Melle, Y. [Tenesol (France)

2006-07-01

Tenesol has specialized in photovoltaic (PV) solar energy since 1983 with experience in grid connections, professional applications, decentralized rural electrification and solar pumping. The company's operations include the manufacture of solar panels, system design and turnkey installations backed by a comprehensive after sales service through a global network of subsidiaries. Half of Tenesol's group shareholdings belong to Electricite de France and half belong to Total. The 2 specialized subsidiaries of Tenesol are Tenesa Manufacturing and Tenesol Technologies. This presentation focused Tenesol's operations in Martinique and its financial environment of grid-connected photovoltaics. It presented Tenesol's approach for technical and economic validation of roof suitability in terms of the disc orientation of PV panels. The key figures of installing a 300 square metre 40 kWp PV system were presented along with photographs of installations in Martinique. The installations have a total installed capacity of 2.5 MWp and an annual solar electricity production of 3,375,000 kWhs, resulting in a reduction of 3,000 tons of carbon dioxide annually. figs.

Connecting Leadership and Learning: Do Versatile Learners make Connective Leaders?

OpenAIRE

Jill L. Robinson

2016-01-01

Recent failures in leadership, suggest that creating better-quality leadership development programs is critical. In moving from theory to practice, this paper examined the relationship between learning style and leadership style which may enable us to move away from one-size-fits-all leadership development programs. Utilizing Kolb’s Experiential Learning Model and Connective Leadership theory, approximately 3600 college students were analyzed to discover whether versatility in learning styles...

Connecting leadership and learning: Do versatile learners make connective leaders?

OpenAIRE

Robinson, Jill L.

2016-01-01

Recent failures in leadership, suggest that creating better-quality leadership development programs is critical. In moving from theory to practice, this paper examined the relationship between learning style and leadership style which may enable us to move away from one-size-fits-all leadership development programs. Utilizing Kolb’s Experiential Learning Model and Connective Leadership theory, approximately 3600 college students were analyzed to discover whether versatility in learning styles...

Connecting Leadership and Learning: Do Versatile Learners make Connective Leaders?

OpenAIRE

Jill L. Robinson

2016-01-01

Abstract Recent failures in leadership, suggest that creating better-quality leadership development programs is critical. In moving from theory to practice, this paper examined the relationship between learning style and leadership style which may enable us to move away from one-size-fits-all leadership development programs. Utilizing Kolb’s Experiential Learning Model and Connective Leadership theory, approximately 3600 college students were analyzed to discover whether versatility in le...

Small Wind Electric Systems: A U.S. Consumer's Guide

International Nuclear Information System (INIS)

O'Dell, K.

2001-01-01

The U.S. Consumer's Guide for Small Wind Electric systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy

Power exchange game in the electricity market

International Nuclear Information System (INIS)

Pyykko, S.; Partanen, J.; Viljainen, S.; Lassila, J.; Honkapuro, S.; Tahvanainen, K.

2006-01-01

Since it is not economically reasonable to build parallel electricity networks, in Finland, Sweden, Norway and Denmark, electricity distribution is protected by monopoly. However, electricity production and selling have been opened up to competition by connecting the transmission networks of these countries together, and it is possible to produce electricity where it is cheapest. A common electricity power market, called Nord Pool, has been created where electricity can be bought, sold or used as an exchange product. In order to help students understand the operation of electricity markets and the use of different electricity exchange products, the Department of Electrical Engineering at Lappeenranta University developed a scheme in which the theory can be used in practice. In the scheme, students are given the responsibility to manage the electricity markets of power companies in order analyze, plan and make decisions, which are skills required on the open power markets. The paper provided an introduction to the electricity markets in Nordic countries and discussed Nord Pool and its products. Information about education at the Department of Electrical Engineering at Lappeenranta University of Technology was also presented. The paper also provided details of the power exchange scheme on the electricity markets. 6 refs., 17 figs

Making Material and Cultural Connections: the fluid meaning of ‘Living Electrically’ in Japan and Canada 1920–1960

Directory of Open Access Journals (Sweden)

Heather Chappells

2018-05-01

Full Text Available This article explores how material and cultural ‘connections’ to households were crucial in defining historical pathways of domestic electrification in Canada and Japan. Though relatively overlooked in the history of energy, we contend that the intricacies of household connections are important in understanding convergence and divergence in electrified ways of life. Electricity’s arrival in urban and rural homes was an uneven process in part due to geographical diversity and the variable connection policies of public or private providers. Selective insights from our two countries show that spatial irregularities in grid expansion and social inequities in the meaning of electrical service further arose out of misalignments between developers’ visions and the diverse material cultures of households. This disparity manifested in the form of disconnections between non-standard wiring and equipment, as well as in the form of consumer resistance, protests and even illicit acts as people fought to get the electrical service they desired. Instead of seeing electrification as a single, universal ideal around which all countries eventually converged, we conclude that it has always been an open-ended, negotiable and culturally fluid process.

Dealing with Demand in Electric Grids with an Adaptive Consumption Management Platform

Directory of Open Access Journals (Sweden)

Diego M. Jiménez-Bravo

2018-01-01

Full Text Available The control of consumption in homes and workplaces is an increasingly important aspect if we consider the growing popularity of smart cities, the increasing use of renewable energies, and the policies of the European Union on using energy in an efficient and clean way. These factors make it necessary to have a system that is capable of predicting what devices are connected to an electrical network. For demand management, the system must also be able to control the power supply to these devices. To this end, we propose the use of a multiagent system that includes agents with advanced reasoning and learning capacities. More specifically, the agents incorporate a case-based reasoning system and machine learning techniques. Besides, the multiagent system includes agents that are specialized in the management of the data acquired and the electrical devices. The aim is to adjust the consumption of electricity in networks to the electrical demand, and this will be done by acting automatically on the detected devices. The proposed system provides promising results; it is capable of predicting what devices are connected to the power grid at a high success rate. The accuracy of the system makes it possible to act according to the device preferences established in the system. This allows for adjusting the consumption to the current demand situation, without the risk of important home appliances being switched off.

Urban fifth graders' connections-making between formal earth science content and their lived experiences

Science.gov (United States)

Brkich, Katie Lynn

2014-03-01

Earth science education, as it is traditionally taught, involves presenting concepts such as weathering, erosion, and deposition using relatively well-known examples—the Grand Canyon, beach erosion, and others. However, these examples—which resonate well with middle- and upper-class students—ill-serve students of poverty attending urban schools who may have never traveled farther from home than the corner store. In this paper, I explore the use of a place-based educational framework in teaching earth science concepts to urban fifth graders and explore the connections they make between formal earth science content and their lived experiences using participant-driven photo elicitation techniques. I argue that students are able to gain a sounder understanding of earth science concepts when they are able to make direct observations between the content and their lived experiences and that when such direct observations are impossible they make analogies of appearance, structure, and response to make sense of the content. I discuss additionally the importance of expanding earth science instruction to include man-made materials, as these materials are excluded traditionally from the curriculum yet are most immediately available to urban students for examination.

Multidimensional Risk Management for Underground Electricity Networks

Directory of Open Access Journals (Sweden)

Garcez Thalles V.

2014-08-01

Full Text Available In the paper we consider an electricity provider company that makes decision on allocating resources on electric network maintenance. The investments decrease malfunction rate of network nodes. An accidental event (explosion, fire, etc. or a malfunctioning on underground system can have various consequences and in different perspectives, such as deaths and injuries of pedestrians, fires in nearby locations, disturbances in the flow of vehicular traffic, loss to the company image, operating and financial losses, etc. For this reason it is necessary to apply an approach of the risk management that considers the multidimensional view of the consequences. Furthermore an analysis of decision making should consider network dependencies between the nodes of the electricity distribution system. In the paper we propose the use of the simulation to assess the network effects (such as the increase of the probability of other accidental event and the occurrence of blackouts of the dependent nodes in the multidimensional risk assessment in electricity grid. The analyzed effects include node overloading due to malfunction of adjacent nodes and blackouts that take place where there is temporarily no path in the grid between the power plant and a node. The simulation results show that network effects have crucial role for decisions in the network maintenance – outcomes of decisions to repair a particular node in the network can have significant influence on performance of other nodes. However, those dependencies are non-linear. The effects of network connectivity (number of connections between nodes on its multidimensional performance assessment depend heavily on the overloading effect level. The simulation results do not depend on network type structure (random or small world – however simulation outcomes for random networks have shown higher variance compared to small-world networks.

Reserving Charging Decision-Making Model and Route Plan for Electric Vehicles Considering Information of Traffic and Charging Station

Directory of Open Access Journals (Sweden)

Haoming Liu

2018-04-01

Full Text Available With the advance of battery energy technology, electric vehicles (EV are catching more and more attention. One of the influencing factors of electric vehicles large-scale application is the availability of charging stations and convenience of charging. It is important to investigate how to make reserving charging strategies and ensure electric vehicles are charged with shorter time and lower charging expense whenever charging request is proposed. This paper proposes a reserving charging decision-making model for electric vehicles that move to certain destinations and need charging services in consideration of traffic conditions and available charging resources at the charging stations. Besides, the interactive mechanism is described to show how the reserving charging system works, as well as the rolling records-based credit mechanism where extra charges from EV is considered to hedge default behavior. With the objectives of minimizing driving time and minimizing charging expenses, an optimization model with two objective functions is formulated. Then the optimizations are solved by a K shortest paths algorithm based on a weighted directed graph, where the time and distance factors are respectively treated as weights of corresponding edges of transportation networks. Case studies show the effectiveness and validity of the proposed route plan and reserving charging decision-making model.

Optimal scheduling for vehicle-to-grid operation with stochastic connection of plug-in electric vehicles to smart grid

International Nuclear Information System (INIS)

Jian, Linni; Zheng, Yanchong; Xiao, Xinping; Chan, C.C.

2015-01-01

Highlights: • A novel event-triggered scheduling scheme for vehicle-to-grid (V2G) operation is proposed. • New scheme can handle the uncertainty arising from stochastic connection of electric vehicles. • New scheme aims at minimizing the overall load variance of power grid by V2G operation. • Method to evaluate the performance of proposed scheme is elaborated and demonstrated. - Abstract: Vehicle-to-grid (V2G) operation of plug-in electric vehicles (PEVs) is attracting increasing attention since it can assist to improve the efficiency and reliability of power grid, as well as reduce the operating cost and greenhouse gas emission of electric vehicles. Within the scheme of V2G operation, PEVs are expected to serve as a novel distributed energy storage system (ESS) to help achieve the balance between supply and demand of power grid. One of the key difficulties concerning its practical implementation lies in that the availability of PEVs as ESS for grid remains highly uncertain due to their mobility as transportation tools. To address this issue, a novel event-triggered scheduling scheme for V2G operation based on the scenario of stochastic PEV connection to smart grid is proposed in this paper. Firstly, the mathematical model is formulated. Secondly, the preparation of input data for systematic evaluation is introduced and the case study is conducted. Finally, statistic analysis results demonstrate that our proposed V2G scheduling scheme can dramatically smooth out the fluctuation in power load profiles

A digital output piezoelectric accelerometer using a Pb(Zr, Ti)O3 thin film array electrically connected in series

International Nuclear Information System (INIS)

Kobayashi, T; Okada, H; Maeda, R; Itoh, T; Masuda, T

2010-01-01

A digital output piezoelectric accelerometer is proposed to realize an ultra-low power consumption wireless sensor node. The accelerometer has patterned piezoelectric thin films (piezoelectric plates) electrically connected in series accompanied by CMOS switches at the end of some of the piezoelectric plates. The connected piezoelectric plates amplify the output voltage without the use of amplifiers. The CMOS switches turn on when the output voltage of the piezoelectric plates is higher than the CMOS threshold voltage. The piezoelectric accelerometer converts the acceleration into a number of on-state CMOS switches, which can be called the digital output. The proposed digital output piezoelectric accelerometer, using Pb(Zr, Ti)O 3 (PZT) thin films as the piezoelectric material, was fabricated through a microelectromechanical system (MEMS) microfabrication process. The output voltage was found to be amplified by the number of connected piezoelectric plates. The DC output voltage obtained by using an AC to DC conversion circuit is proportional to the number of connections. The results show the potential for realizing the proposed digital output piezoelectric accelerometer

Small Wind Electric Systems: A Kansas Consumer's Guide

International Nuclear Information System (INIS)

O'Dell, K.

2001-01-01

The Kansas Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of state incentives and state contacts for more information

Undifferentiated Connective Tissue Disease

Science.gov (United States)

... Home Conditions Undifferentiated Connective Tissue Disease (UCTD) Undifferentiated Connective Tissue Disease (UCTD) Make an Appointment Find a Doctor ... by Barbara Goldstein, MD (February 01, 2016) Undifferentiated connective tissue disease (UCTD) is a systemic autoimmune disease. This ...

Connecting Colorado's Renewable Resources to the Markets in a Cabon-Constrained Electricity Sector

Energy Technology Data Exchange (ETDEWEB)

None

2009-12-31

The benchmark goal that drives the report is to achieve a 20 percent reduction in carbon dioxide (CO{sub 2}) emissions in Colorado's electricity sector below 2005 levels by 2020. We refer to this as the '20 x 20 goal.' In discussing how to meet this goal, the report concentrates particularly on the role of utility-scale renewable energy and high-voltage transmission. An underlying recognition is that any proposed actions must not interfere with electric system reliability and should minimize financial impacts on customers and utilities. The report also describes the goals of Colorado's New Energy Economy5 - identified here, in summary, as the integration of energy, environment, and economic policies that leads to an increased quality of life in Colorado. We recognize that a wide array of options are under constant consideration by professionals in the electric industry, and the regulatory community. Many options are under discussion on this topic, and the costs and benefits of the options are inherently difficult to quantify. Accordingly, this report should not be viewed as a blueprint with specific recommendations for the timing, siting, and sizing of generating plants and high-voltage transmission lines. We convened the project with the goal of supplying information inputs for consideration by the state's electric utilities, legislators, regulators, and others as we work creatively to shape our electricity sector in a carbon-constrained world. The report addresses various issues that were raised in the Connecting Colorado's Renewable Resources to the Markets report, also known as the SB07-91 Report. That report was produced by the Senate Bill 2007-91 Renewable Resource Generation Development Areas Task Force and presented to the Colorado General Assembly in 2007. The SB07-91 Report provided the Governor, the General Assembly, and the people of Colorado with an assessment of the capability of Colorado's utility-scale renewable

Electricity generation and microbial community in response to short-term changes in stack connection of self-stacked submersible microbial fuel cell powered by glycerol

DEFF Research Database (Denmark)

Zhao, Nannan; Angelidaki, Irini; Zhang, Yifeng

2017-01-01

community. In this study, a self-stacked submersible microbial fuel cell (SSMFC) powered by glycerol was tested to elucidate this important issue. In series connection, the maximum voltage output reached to 1.15 V, while maximum current density was 5.73 mA in parallel. In both connections, the maximum power......Stack connection (i.e., in series or parallel) of microbial fuel cell (MFC) is an efficient way to boost the power output for practical application. However, there is little information available on short-term changes in stack connection and its effect on the electricity generation and microbial...... density increased with the initial glycerol concentration. However, the glycerol degradation was even faster in parallel connection. When the SSMFC was shifted from series to parallel connection, the reactor reached to a stable power output without any lag phase. Meanwhile, the anodic microbial community...

Connected smart sensors make super-smart buildings; Connected smart sensors maken gebouwen superslim

Energy Technology Data Exchange (ETDEWEB)

Van der Veen, J.K.

2012-10-15

In 2020, between 20 and 50 billion appliances will be connected to the internet and exchange information, usually without human intervention. A large part will consist of smart, autonomous sensors that generate their own supply voltage and have wireless connection with the web. The 'internet of things' offers dazzling opportunities for smart buildings [Dutch] In 2020 zullen tussen de twintig en vijftig miljard apparaten met internet verbonden zijn en, veelal zonder tussenkomst van mensen, informatie uitwisselen. Een groot deel hiervan zal bestaan uit slimme, autonome sensoren, die hun eigen voedingsspanning opwekken en draadloos met het web zijn verbonden. Voor slimme gebouwen biedt 'the internet of things' duizelingwekkende mogelijkheden.

A universal approach to electrically connecting nanowire arrays using nanoparticles—application to a novel gas sensor architecture

Science.gov (United States)

Parthangal, Prahalad M.; Cavicchi, Richard E.; Zachariah, Michael R.

2006-08-01

We report on a novel, in situ approach toward connecting and electrically contacting vertically aligned nanowire arrays using conductive nanoparticles. The utility of the approach is demonstrated by development of a gas sensing device employing this nano-architecture. Well-aligned, single-crystalline zinc oxide nanowires were grown through a direct thermal evaporation process at 550 °C on gold catalyst layers. Electrical contact to the top of the nanowire array was established by creating a contiguous nanoparticle film through electrostatic attachment of conductive gold nanoparticles exclusively onto the tips of nanowires. A gas sensing device was constructed using such an arrangement and the nanowire assembly was found to be sensitive to both reducing (methanol) and oxidizing (nitrous oxides) gases. This assembly approach is amenable to any nanowire array for which a top contact electrode is needed.

A universal approach to electrically connecting nanowire arrays using nanoparticles-application to a novel gas sensor architecture

International Nuclear Information System (INIS)

Parthangal, Prahalad M; Cavicchi, Richard E; Zachariah, Michael R

2006-01-01

We report on a novel, in situ approach toward connecting and electrically contacting vertically aligned nanowire arrays using conductive nanoparticles. The utility of the approach is demonstrated by development of a gas sensing device employing this nano-architecture. Well-aligned, single-crystalline zinc oxide nanowires were grown through a direct thermal evaporation process at 550 deg. C on gold catalyst layers. Electrical contact to the top of the nanowire array was established by creating a contiguous nanoparticle film through electrostatic attachment of conductive gold nanoparticles exclusively onto the tips of nanowires. A gas sensing device was constructed using such an arrangement and the nanowire assembly was found to be sensitive to both reducing (methanol) and oxidizing (nitrous oxides) gases. This assembly approach is amenable to any nanowire array for which a top contact electrode is needed

Magnitude and Variability of Controllable Charge Capacity Provided by Grid Connected Plug-in Electric Vehicles

Energy Technology Data Exchange (ETDEWEB)

Scoffield, Don R [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smart, John [Idaho National Lab. (INL), Idaho Falls, ID (United States); Salisbury, Shawn [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-03-01

As market penetration of plug-in electric vehicles (PEV) increases over time, the number of PEVs charging on the electric grid will also increase. As the number of PEVs increases, their ability to collectively impact the grid increases. The idea of a large body of PEVs connected to the grid presents an intriguing possibility. If utilities can control PEV charging, it is possible that PEVs could act as a distributed resource to provide grid services. The technology required to control charging is available for modern PEVs. However, a system for wide-spread implementation of controllable charging, including robust communication between vehicles and utilities, is not currently present. Therefore, the value of controllable charging must be assessed and weighed against the cost of building and operating such as system. In order to grasp the value of PEV charge control to the utility, the following must be understood: 1. The amount of controllable energy and power capacity available to the utility 2. The variability of the controllable capacity from day to day and as the number of PEVs in the market increases.

Electric vehicle battery charging controller

DEFF Research Database (Denmark)

2016-01-01

The present invention provides an electric vehicle charging controller. The charging controller comprises a first interface connectable to an electric vehicle charge source for receiving a charging current, a second interface connectable to an electric vehicle for providing the charging current...... to a battery management system in the electric vehicle to charge a battery therein, a first communication unit for receiving a charging message via a communication network, and a control unit for controlling a charging current provided from the charge source to the electric vehicle, the controlling at least...... in part being performed in response to a first information associated with a charging message received by the first communication unit...

Optimal Decision Making Framework of an Electric Vehicle Aggregator in Future and Pool markets

DEFF Research Database (Denmark)

Rashidizadeh-Kermani, Homa; Najafi, Hamid Reza; Anvari-Moghaddam, Amjad

2018-01-01

An electric vehicle (EV) aggregator, as an agent between power producers and EV owners, participates in the future and pool market to supply EVs’ requirement. Because of uncertain nature of pool prices and EVs’ behavior, this paper proposed a two stage scenario-based model to obtain optimal decis...... electricity markets, a sensitivity analysis over risk factor is performed. The numerical results demonstrate that with the application of the proposed model, the aggregator can supply EVs with lower purchases from markets....... decision making of an EV aggregator. To deal with mentioned uncertainties, the aggregator’s risk aversion is applied using conditional value at risk (CVaR) method in the proposed model. The proposed two stage risk-constrained decision making problem is applied to maximize EV aggregator’s expected profit...... in an uncertain environment. The aggregator can participate in the future and pool market to buy required energy of EVs and offer optimal charge/discharge prices to the EV owners. In this model, in order to assess the effects of EVs owners’ reaction to the aggregator’s offered prices on the purchases from...

Family Connections: Building Connections among Home, School, and Community

Science.gov (United States)

Dikkers, Amy Garrett

2013-01-01

Recent research on parental involvement has explored connections between parental involvement in school and children's academic achievement. While many schools have active parent organizations and a base of parents who offer additional support, others struggle to make connections with their parents or community members. Even in places with active…

Decision Making in the Connected Learning Environment (CLE

Directory of Open Access Journals (Sweden)

Anas Belahcen

2016-03-01

Full Text Available In the last years, we have witnessed to an increasingly heightened awareness of the potential benefits of a challenging and promising educational research area : Adaptive Learning [1]. It has become one of the central technologies in education [2] and was recently named, by Gartner, as the number one strategic technology to impact education in 2015 [3]. In fact, adaptive learning systems become more accessible to educational institutions, corporations, and individuals, however, the challenges encountered are more structural and operational rather than technological [4]. While a lot of research has focused on development and evaluation of technological aspects [5], serious questions remain about the motivation of learners [6],[7] and also the design of the content (or domain model [8],[9] including the learner's autonomy issues [9],[10],[11] and the lack of the learner's control [9],[12],[13]. In order to overcome those challenges, we propose CLE “Connected Learning Environment” which is an ubiquitous learning environment [14] that provide to the learners of this generation a learning environment adapted to their expectations and their lifestyle habits and stimulate also their motivation. As a pedagogical approach, CLE adopts the connectivism [15] and take advantage from its benefits (adaptation to the current technological advances [16], management of learning in communities [17], openness with respect to external resources[18], etc. and adapts this approach in a formal context even though the connectivism was conceived as an informal pedagogical approach [19][20]. CLE introduces a new pedagogical process including four phases detailed later (Knowledge construction, Decision making, Validation, Evaluation and the knowledge construction phase is characterized by the collaboration and communication between heterogeneous communities composed of humans and smart objects [14]. However, the ability to distinguish relevant information among the

Negative symptoms in schizophrenia are associated with aberrant striato-cortical connectivity in a rewarded perceptual decision-making task.

Science.gov (United States)

Reckless, Greg E; Andreassen, Ole A; Server, Andres; Østefjells, Tiril; Jensen, Jimmy

2015-01-01

Negative symptoms in schizophrenia have been associated with structural and functional changes in the prefrontal cortex. They often persist after treatment with antipsychotic medication which targets, in particular, the ventral striatum (VS). As schizophrenia has been suggested to arise from dysfunctional connectivity between neural networks, it is possible that residual aberrant striato-cortical connectivity in medicated patients plays a role in enduring negative symptomology. The present study examined the relationship between striato-cortical connectivity and negative symptoms in medicated schizophrenia patients. We manipulated motivation in a perceptual decision-making task during functional magnetic resonance imaging. Comparing healthy controls (n = 21) and medicated patients with schizophrenia (n = 18) we investigated how motivation-mediated changes in VS activation affected functional connectivity with the frontal cortex, and how changes in connectivity strength from the neutral to motivated condition related to negative symptom severity. A pattern of aberrant striato-cortical connectivity was observed in the presence of intact VS, but altered left inferior frontal gyrus (IFG) motivation-mediated activation in patients. The more severe the patient's negative symptoms, the less the connectivity strength between the right VS and left IFG changed from the neutral to the motivated condition. Despite aberrant striato-cortical connectivity and altered recruitment of the left IFG among patients, both patients and healthy controls adopted a more liberal response strategy in the motivated compared to the neutral condition. The present findings suggest that there is a link between dysfunctional striato-cortical connectivity and negative symptom severity, and offer a possible explanation as to why negative symptoms persist after treatment with antipsychotics.

Developing a DSR-HNS policy making framework for electric energy systems

International Nuclear Information System (INIS)

Meyar-Naimi, H.; Vaez-Zadeh, S.

2012-01-01

Sustainable Development (SD) has played a major role as a foundation of several policy making frameworks developed mainly by international organizations. In this paper, some critical points regarding the origination and formulation of the SD concept are discussed. It is argued that the SD concerns with selected sectors and regions rather than the whole society and all regions of the world. To tackle these shortcomings, the conventional definition of SD is extended in this paper according to a broad philosophy of harmonizing key aspects of human, nature and systems performances over generations. Based on this extended definition, an improved Driving Force–State–Response (DSR-HNS) policy making framework is introduced. The main contribution is the modeling of the state block by human, nature and systems components to design overall and coherent policies. A procedure using the framework is also elaborated to monitor the current policies and design new ones, which provides a dynamic, nonlinear, feedback controlled policy making practice, not accommodated by existing policy making frameworks. Finally, a case study is presented to evaluate the effectiveness of the modified framework and the proposed model. The study assesses Iran's electric power generation system from sustainability point of view and develops new policies. - Highlights: ► Some critical points regarding the Sustainable Development (SD) concept are discussed. ► Based on this extended definition, a policy making framework is introduced. ► A policy making procedure based on the framework is elaborated. ► A case study is presented to evaluate the effectiveness of the modified framework. ► New policies are developed for Iran's power generation system.

Multiobjective Synergistic Scheduling Optimization Model for Wind Power and Plug-In Hybrid Electric Vehicles under Different Grid-Connected Modes

Directory of Open Access Journals (Sweden)

Liwei Ju

2014-01-01

Full Text Available In order to promote grid’s wind power absorptive capacity and to overcome the adverse impacts of wind power on the stable operation of power system, this paper establishes benefit contrastive analysis models of wind power and plug-in hybrid electric vehicles (PHEVs under the optimization goal of minimum coal consumption and pollutant emission considering multigrid connected modes. Then, a two-step adaptive solving algorithm is put forward to get the optimal system operation scheme with the highest membership degree based on the improved ε constraints method and fuzzy decision theory. Thirdly, the IEEE36 nodes 10-unit system is used as the simulation system. Finally, the sensitive analysis for PHEV’s grid connected number is made. The result shows the proposed algorithm is feasible and effective to solve the model. PHEV’s grid connection could achieve load shifting effect and promote wind power grid connection. Especially, the optimization goals reach the optimum in fully optimal charging mode. As PHEV’s number increases, both abandoned wind and thermal power generation cost would decrease and the peak and valley difference of load curve would gradually be reduced.

Electric Field Effects in RUS Measurements

Energy Technology Data Exchange (ETDEWEB)

Darling, Timothy W [Los Alamos National Laboratory; Ten Cate, James A [Los Alamos National Laboratory; Allured, Bradley [UNIV NEVADA, RENO; Carpenter, Michael A [CAMBRIDGE UNIV. UK

2009-09-21

Much of the power of the Resonant Ultrasound Spectroscopy (RUS) technique is the ability to make mechanical resonance measurements while the environment of the sample is changed. Temperature and magnetic field are important examples. Due to the common use of piezoelectric transducers near the sample, applied electric fields introduce complications, but many materials have technologically interesting responses to applied static and RF electric fields. Non-contact optical, buffered, or shielded transducers permit the application of charge and externally applied electric fields while making RUS measurements. For conducting samples, in vacuum, charging produces a small negative pressure in the volume of the material - a state rarely explored. At very high charges we influence the electron density near the surface so the propagation of surface waves and their resonances may give us a handle on the relationship of electron density to bond strength and elasticity. Our preliminary results indicate a charge sign dependent effect, but we are studying a number of possible other effects induced by charging. In dielectric materials, external electric fields influence the strain response, particularly in ferroelectrics. Experiments to study this connection at phase transformations are planned. The fact that many geological samples contain single crystal quartz suggests a possible use of the piezoelectric response to drive vibrations using applied RF fields. In polycrystals, averaging of strains in randomly oriented crystals implies using the 'statistical residual' strain as the drive. The ability to excite vibrations in quartzite polycrystals and arenites is explored. We present results of experimental and theoretical approaches to electric field effects using RUS methods.

Small Wind Electric Systems An Alaska Consumer's Guide

International Nuclear Information System (INIS)

O'Dell, K.

2001-01-01

The Alaska Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a state wind resource map and a list of state incentives and state contacts for more information

Small Wind Electric Systems: A Vermont Consumer's Guide

International Nuclear Information System (INIS)

O'Dell, K.

2001-01-01

The Vermont Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a state wind resource map and a list of state incentives and state contacts for more information

Mathematic model of three-phase induction machine connected to advanced inverter for traction system for electric trolley

Directory of Open Access Journals (Sweden)

LIVIU S. BOCÎI

2013-06-01

Full Text Available This paper establishes a mathematical model of induction machine connected to a frequency inverter necessary to adjust the electric motor drive. The mathematical model based on the Park's theory allows the analysis of the whole spectrum (electric car – frequency inverter to drive the electric trolley bus made on ASTRA Bus Arad (Romania. To remove higher order harmonics, the PWM waveform of supply voltage is used, set in the general case. Operating characteristics of electric motor drive are set to sub-nominal frequency (f Bele 2007.Este documento estabelece um modelo matemático de máquina de indução conectado a um inversor de frequência necessário para ajustar o motor de acionamento elétrico. O modelo matemático baseado na Teoria de Park permite a análise de todo o espectro (carro elétrico com inversor de frequência para dirigir o ônibus elétrico feito em ASTRA Bus Arad (Romênia. Para remover harmônicas de ordem mais alta, a forma de onda da tensão de alimentação PWM é utilizado, definido no caso geral. Características de funcionamento do motor de acionamento elétrico são definidas para frequência sub-nominal (f

Electric Power Substitute Meter Management via Mobile Application

Directory of Open Access Journals (Sweden)

Nelson C. Rodelas

2014-10-01

Full Text Available EPSMvMA is composed of Digital Sub-Meter connected to different components namely the GSM module, Bluetooth module, Power Analyzer Module, LCD Module, Relay Module and Main Microcontroller module. The connection via Mobile is made possible by the modules mentioned. The software that the proponents will be dealing with in the study is C++ language, which will be used in programming the Main Microcontroller module and Visual Basic Language for the Android Phones. The Bluetooth module can access the Android Phones and connect to the digital sub-meter in a limited distance. The users will be at ease since a code embedded to the microcontroller will make the utility sub-meter produce the desired value of electricity (KWH and wherein the computed Sub-meter reading can be viewed through the LCD. This project is accommodating to those person that is always on the go and prudent.

Program For Engineering Electrical Connections

Science.gov (United States)

Billitti, Joseph W.

1990-01-01

DFACS is interactive multiuser computer-aided-engineering software tool for system-level electrical integration and cabling engineering. Purpose of program to provide engineering community with centralized data base for putting in and gaining access to data on functional definition of system, details of end-circuit pinouts in systems and subsystems, and data on wiring harnesses. Objective, to provide instantaneous single point of interchange of information, thus avoiding error-prone, time-consuming, and costly shuttling of data along multiple paths. Designed to operate on DEC VAX mini or micro computer using Version 5.0/03 of INGRES.

High thermal conductivity connector having high electrical isolation

Science.gov (United States)

Nieman, Ralph C.; Gonczy, John D.; Nicol, Thomas H.

1995-01-01

A method and article for providing a low-thermal-resistance, high-electrical-isolation heat intercept connection. The connection method involves clamping, by thermal interference fit, an electrically isolating cylinder between an outer metallic ring and an inner metallic disk. The connection provides durable coupling of a heat sink and a heat source.

Method and device for current driven electric energy conversion

DEFF Research Database (Denmark)

2012-01-01

Device comprising an electric power converter circuit for converting electric energy. The converter circuit comprises a switch arrangement with two or more controllable electric switches connected in a switching configuration and controlled so as to provide a current drive of electric energy from...... configurations such as half bridge buck, full bridge buck, half bridge boost, or full bridge boost. A current driven conversion is advantageous for high efficient energy conversion from current sources such as solar cells or where a voltage source is connected through long cables, e.g. powerline cables for long...... an associated electric source connected to a set of input terminals. This is obtained by the two or more electric swiches being connected and controlled to short-circuit the input terminals during a part of a switching period. Further, a low pass filter with a capacitor and an inductor are provided to low pass...

National campaign - 100 collectivities connected to the green electric power

International Nuclear Information System (INIS)

2004-01-01

Since july 2004, the local collectivities, the little and medium enterprises and the craft workers can choose their electric power supplier. This offer can be a chance for the renewable energy. The association ''eco maires'' with the help of the WWF began a campaign to obtain the involvement of 100 collectivities interested by the green electric power. The project is presented. The authors presents also the new European Network on the green electric power, Eugene (European Green Electricity Network), which aims to harmonize criteria on the green electric power and to deliver certificates of quality. (A.L.B.)

Mapping effective connectivity in the human brain with concurrent intracranial electrical stimulation and BOLD-fMRI.

Science.gov (United States)

Oya, Hiroyuki; Howard, Matthew A; Magnotta, Vincent A; Kruger, Anton; Griffiths, Timothy D; Lemieux, Louis; Carmichael, David W; Petkov, Christopher I; Kawasaki, Hiroto; Kovach, Christopher K; Sutterer, Matthew J; Adolphs, Ralph

2017-02-01

Understanding brain function requires knowledge of how one brain region causally influences another. This information is difficult to obtain directly in the human brain, and is instead typically inferred from resting-state fMRI. Here, we demonstrate the safety and scientific promise of a novel and complementary approach: concurrent electrical stimulation and fMRI (es-fMRI) at 3T in awake neurosurgical patients with implanted depth electrodes. We document the results of safety testing, actual experimental setup, and stimulation parameters, that safely and reliably evoke activation in distal structures through stimulation of amygdala, cingulate, or prefrontal cortex. We compare connectivity inferred from the evoked patterns of activation with that estimated from standard resting-state fMRI in the same patients: while connectivity patterns obtained with each approach are correlated, each method produces unique results. Response patterns were stable over the course of 11min of es-fMRI runs. COMPARISON WITH EXISTING METHOD: es-fMRI in awake humans yields unique information about effective connectivity, complementing resting-state fMRI. Although our stimulations were below the level of inducing any apparent behavioral or perceptual effects, a next step would be to use es-fMRI to modulate task performances. This would reveal the acute network-level changes induced by the stimulation that mediate the behavioral and cognitive effects seen with brain stimulation. es-fMRI provides a novel and safe approach for mapping effective connectivity in the human brain in a clinical setting, and will inform treatments for psychiatric and neurodegenerative disorders that use deep brain stimulation. Copyright © 2016 Elsevier B.V. All rights reserved.

Embedded generation connection incentives for distribution network operators

Energy Technology Data Exchange (ETDEWEB)

Williams, P.; Andrews, S.

2002-07-01

This is the final report with respect to work commissioned by the Department of Trade and Industry (DTI) as part of the New and Renewable Energy Programme into incentives for distribution network operators (DNOs) for the connection of embedded generation. This report, which incorporates the contents of the interim report submitted in February 2002, considers the implications of changes in the structure and regulation in the UK electricity industry on the successful technical and commercial integrated of embedded generation into distribution networks. The report examines: the obligations of public electricity suppliers (PESs); current DNO practices regarding the connection of embedded generation; the changes introduced by the Utilities Act 2000, including the impact of new obligations placed on DNOs on the connection of embedded generation and the requirements of the new Electricity Distribution Standard Licence conditions; and problems and prospects for DNO incentives.

Design optimization of grid-connected PV inverters

DEFF Research Database (Denmark)

Koutroulis, Eftichios; Blaabjerg, Frede

2011-01-01

The DC/AC inverters are the key elements in grid-connected PV energy production systems. In this paper, new design optimization techniques focused on transformerless (very high efficiency) PV inverters are proposed. They have been developed based on an analysis of the deficiencies of the current......, state-of-the-art PV inverters design technology, which limits the amount of PV energy supplied into the electric grid. The influences of the electric grid regulations and standards and the PV array operational characteristics on the design of grid-connected PV inverters have also been considered....... The simulation results verify that the proposed optimization techniques enable the maximization of the PV energy injected into the electric grid by the optimized PV installation....

Apparatus for deploying and energizing submersible electric motor downhole

International Nuclear Information System (INIS)

Conner, S.E.; Dwiggins, J.L.; Brookbank, E.B.

1991-01-01

This patent describes an apparatus for deploying and energizing a submergible electric motor downhole. It comprises a cable socket assembly and a cable connecting-and-sealing chamber assembly adapted to be arranged seriatim in the path of cable means and the motor, the assemblies having first and second housings, respectively, means for connecting a lower end of the first housing to an upper end of the second housing, a lower end of the second housing being adapted for connection to the motor, the cable socket assembly having an attachment portion including means for attaching a weight-bearing cable of the cable means to the first housing via a breakaway connection, the first housing having a passage therein adapted to pass an electrical cable of the cable means to the second housing, the second housing being divided by a body therein into first and second chambers sealed from each other, the first chamber being adapted to communicate sealingly with the passage and the second chamber being adapted to communicate sealingly with the interior of the motor, a first set of electrical conductors in the first chamber and a second set of electrical conductors in the second chamber, the body having feed-through means for electrically interconnecting conductors of the first set with corresponding conductors of the second set, the conductors of the first set having electrical connector parts adapted to connect releasably with corresponding electrical connector parts of the electrical cable, and the conductors of the second set having electrical connector parts adapted to connect with corresponding electrical connector parts of the motor, each of the chambers being adapted to be filled with fluid to exclude well fluid therefrom

Optimization Under Uncertainty for Management of Renewables in Electricity Markets

DEFF Research Database (Denmark)

Zugno, Marco

-by-price. In a similar setup, the optimal trading (and pricing) problem for a retailer connected to flexible consumers is considered. Finally, market and system operators are challenged by the increasing penetration of renewables, which put stress on markets that were designed to accommodate a generation mix largely......This thesis deals with the development and application of models for decision-making under uncertainty to support the participation of renewables in electricity markets. The output of most renewable sources, e.g., wind, is intermittent and, furthermore, it can only be predicted with a limited...... accuracy. As a result of their non-dispatchable and stochastic nature, the management of renewables poses new challenges as compared to conventional sources of electricity. Focusing in particular on short-term electricity markets, both the trading activities of market participants (producers, retailers...

Small Wind Electric Systems: A New Mexico Consumer's Guide

International Nuclear Information System (INIS)

O'Dell, K.

2001-01-01

The New Mexico Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a state wind resource map and a list of state incentives and state contacts for more information

Small Wind Electric Systems: A South Dakota Consumer's Guide

International Nuclear Information System (INIS)

O'Dell, K.

2001-01-01

The South Dakota Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a state wind resource map and a list of state incentives and state contacts for more information

30 CFR 18.49 - Connection boxes on machines.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Connection boxes on machines. 18.49 Section 18..., AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.49 Connection boxes on machines. Connection boxes used to facilitate replacement...

Hippocampal-Prefrontal Circuit and Disrupted Functional Connectivity in Psychiatric and Neurodegenerative Disorders

Directory of Open Access Journals (Sweden)

Ming Li

2015-01-01

Full Text Available In rodents, the hippocampus has been studied extensively as part of a brain system responsible for learning and memory, and the prefrontal cortex (PFC participates in numerous cognitive functions including working memory, flexibility, decision making, and rewarding learning. The neuronal projections from the hippocampus, either directly or indirectly, to the PFC, referred to as the hippocampal-prefrontal cortex (Hip-PFC circuit, play a critical role in cognitive and emotional regulation and memory consolidation. Although in certain psychiatric and neurodegenerative diseases, structural connectivity viewed by imaging techniques has been consistently found to be associated with clinical phenotype and disease severity, the focus has moved towards the investigation of connectivity correlates of molecular pathology and coupling of oscillation. Moreover, functional and structural connectivity measures have been emerging as potential intermediate biomarkers for neuronal disorders. In this review, we summarize progress on the anatomic, molecular, and electrophysiological characters of the Hip-PFC circuit in cognition and emotion processes with an emphasis on oscillation and functional connectivity, revealing a disrupted Hip-PFC connectivity and electrical activity in psychiatric and neurodegenerative disorders as a promising candidate of neural marker for neuronal disorders.

Are PES connection costs too high?

International Nuclear Information System (INIS)

Scott, N.

1998-01-01

Windfarm developers often have good reason to question the costs they are quoted by their local distribution company for connection to the system, and these costs can now be challenged under the 'Competition in Connection' initiative. Econnect Ltd specialise in electrical connections for renewable generation throughout the UK and Europe, and have worked on many projects where alternative connections have been designed at more competitive prices. This paper provides some examples which illustrate the importance of acquiring a thorough understanding of all power system issues and PES concerns if the most cost-effective connection is to be realised. (Author)

Electricity, health and the environment: Comparative assessment in support of decision making. Proceedings of a symposium

International Nuclear Information System (INIS)

1996-01-01

The main objective of the Symposium was to enhance and strengthen information sharing and co-operation between interested and affected parties in the field of electricity demand analysis and supply planning, aiming at implementing sustainable policies in the power sector, taking into account economic, social, health and environmental aspects. To meet this objective, the Symposium sessions addressed the following topics: key issues in the decision making process; assessment of health and environmental impacts; integrated framework for comparative assessment; implementation of comparative assessment; country case studies; and comparative assessment in decision making. A closing round table focused on challenges for international co-operation aiming at implementation of sustainable electricity policies. In addition to the main sessions, poster presentations illustrated results from comparative assessment studies carried out in different countries, and software demonstration provided opportunities for participants to gain information about state of the art computer tools, databases and analytical models that are available for use in decision support studies. Refs, figs, tabs

Optimal Dispatch of Unreliable Electric Grid-Connected Diesel Generator-Battery Power Systems

Science.gov (United States)

Xu, D.; Kang, L.

2015-06-01

Diesel generator (DG)-battery power systems are often adopted by telecom operators, especially in semi-urban and rural areas of developing countries. Unreliable electric grids (UEG), which have frequent and lengthy outages, are peculiar to these regions. DG-UEG-battery power system is an important kind of hybrid power system. System dispatch is one of the key factors to hybrid power system integration. In this paper, the system dispatch of a DG-UEG-lead acid battery power system is studied with the UEG of relatively ample electricity in Central African Republic (CAR) and UEG of poor electricity in Congo Republic (CR). The mathematical models of the power system and the UEG are studied for completing the system operation simulation program. The net present cost (NPC) of the power system is the main evaluation index. The state of charge (SOC) set points and battery bank charging current are the optimization variables. For the UEG in CAR, the optimal dispatch solution is SOC start and stop points 0.4 and 0.5 that belong to the Micro-Cycling strategy and charging current 0.1 C. For the UEG in CR, the optimal dispatch solution is of 0.1 and 0.8 that belongs to the Cycle-Charging strategy and 0.1 C. Charging current 0.1 C is suitable for both grid scenarios compared to 0.2 C. It makes the dispatch strategy design easier in commercial practices that there are a few very good candidate dispatch solutions with system NPC values close to that of the optimal solution for both UEG scenarios in CAR and CR.

Economic impact assessment and operational decision making in emission and transmission constrained electricity markets

International Nuclear Information System (INIS)

Nanduri, Vishnu; Kazemzadeh, Narges

2012-01-01

Highlights: ► We develop a bilevel game-theoretic model for allowance and electricity markets. ► We solve the model using a reinforcement learning algorithm. ► Model accounts for transmission constraints, cap-and-trade constraints. ► Study demonstrated on 9-bus electric power network. ► Obtain insights about supply shares, impact of transmission constraints, and cost pass through. -- Abstract: Carbon constrained electricity markets are a reality in 10 northeastern states and California in the US, as well as the European Union. Close to a Billion US Dollars have been spent by entities (mainly generators) in the Regional Greenhouse Gas Initiative in procuring CO 2 allowances to meet binding emissions restrictions. In the near future, there are expected to be significant impacts due to the cap-and-trade program, especially when the cap stringency increases. In this research we develop a bilevel, complete-information, matrix game-theoretic model to assess the economic impact and make operational decisions in carbon-constrained restructured electricity markets. Our model is solved using a reinforcement learning approach, which takes into account the learning and adaptive nature of market participants. Our model also accounts for all the power systems constraints via a DC-OPF problem. We demonstrate the working of the model and compute various economic impact indicators such as supply shares, cost pass-through, social welfare, profits, allowance prices, and electricity prices. Results from a 9-bus power network are presented.

Assembly for electrical conductivity measurements in the piston cylinder device

Science.gov (United States)

Watson, Heather Christine [Dublin, CA; Roberts, Jeffrey James [Livermore, CA

2012-06-05

An assembly apparatus for measurement of electrical conductivity or other properties of a sample in a piston cylinder device wherein pressure and heat are applied to the sample by the piston cylinder device. The assembly apparatus includes a body, a first electrode in the body, the first electrode operatively connected to the sample, a first electrical conductor connected to the first electrode, a washer constructed of a hard conducting material, the washer surrounding the first electrical conductor in the body, a second electrode in the body, the second electrode operatively connected to the sample, and a second electrical conductor connected to the second electrode.

Connecting Representations: Using Predict, Check, Explain

Science.gov (United States)

Roy, George J.; Fueyo, Vivian; Vahey, Philip; Knudsen, Jennifer; Rafanan, Ken; Lara-Meloy, Teresa

2016-01-01

Although educators agree that making connections with the real world, as advocated by "Principles to Actions: Ensuring Mathematical Success for All" (NCTM 2014), is important, making such connections while addressing important mathematics is elusive. The authors have found that math content coupled with the instructional strategy of…

Economic performance and policies for grid-connected residential solar photovoltaic systems in Brazil

International Nuclear Information System (INIS)

Mitscher, Martin; Rüther, Ricardo

2012-01-01

We analyze the economic competitiveness of grid-connected, distributed solar photovoltaic generation through small-scale rooftop installations in five Brazilian state-capitals. The locations represent a comprehensive set of the two essential parameters for the economic viability of PV—solar irradiation and local electricity tariffs. Levelized electricity costs (LEC) for PV generation and net present values (NPV) for a specific PV system are presented. The analysis comprises three different interest rate scenarios reflecting different conditions for capital acquisition to finance the generators; subsidized, mature market and country-specific risk-adjusted interest. In the NPV analysis, revenue flow is modeled by the sale of PV electricity at current residential tariffs assuming net metering. Using subsidized interest rates, the analysis shows that solar PV electricity is already competitive in Brazil, while in the country-specific risk-adjusted rate, the declining, but still high capital costs of PV make it economically unfeasible. At a mature market interest rate, PV competitiveness is largely dependent on the residential tariff. Economic competitiveness in this scenario is given for locations with high residential tariffs. We demonstrate the high potential of distributed generation with photovoltaic installations in Brazil, and show that under certain conditions, grid-connected PV can be economically competitive in a developing country. - Highlights: ► Debt financed grid-connected PV on Brazilian rooftops can be economically feasible since 2011. ► The cost of capital in Brazil is the decisive parameter in PV competitiveness with conventional generation sources. ► Low-cost, long-term financing is an essential requirement for PV to become an economically justifiable generation alternative. ► The Brazilian market holds huge potential for distributed, residential rooftop PV systems of small size.

Technical guide to the connection of generation to the distribution network

Energy Technology Data Exchange (ETDEWEB)

Jarrett, K.; Hedgecock, J.; Gregory, R.; Warham, T.

2003-07-01

This guide provides a 'route map' of the processes of getting a generation scheme connected to the network and is intended to help developers of any form of distributed generation connected to the UK's local electricity networks, eg: renewable energy schemes; waste-to-energy schemes; on-site generation and combined heat and power (CHP) schemes; and peak lopping schemes using back-up generators. Where necessary, the guide distinguishes between arrangements that apply in Scotland and those that apply in England and Wales. The guide aims to: provide background information about the electricity industry; highlight common technical issues that arise during connection negotiation and their implications for distribution network operators (DNOs) and developers; examine the main factors affecting connection costs and timescales for achieving connections; and identify the different types of contracts relating to connection. The report considers the connection process, the connection application process and timescales, costs and charges, competition in connection, the structure of the UK electricity industry, the statutory framework, the effects of distributed generation of the distribution system, earthing and protection design, safety issues and DNO network information. It includes a glossary, checklists, useful contact details and information about standards and other useful documents.

Seeking common ground: making connections big and small

Directory of Open Access Journals (Sweden)

David Lee Keiser

2017-11-01

Full Text Available Purpose – This essay furthers cross-cultural exchange, and understanding. Written for a general audience by a teacher educator, it argues for accepting all others into the academic conversation. Using varied examples, the purpose of this paper is to illustrate both lifelong learning and the power of connecting across difference. Design/methodology/approach – The author draws upon experience as a teacher and professor and his engagement with Kingdom of Saudi Arabia (KSA for examples of edification and engagement. Findings – The author cites both the current period and a mid-twentieth-century American major event, the civil rights March on Washington to illustrate possibilities for connection, clarity and symbiosis. Originality/value – Written for this journal, this essay uses an original and skeletal theoretical and empirical frame as well as field examples to argue for inclusiveness, exchange and acceptance of all learners.

IMPROVED ALGORITHM FOR CALCULATING COMPLEX NON-EQUIPOTENTIAL GROUNDING DEVICES OF ELECTRICAL INSTALLATIONS TAKING INTO ACCOUNT CONDUCTIVITY OF NATURAL GROUNDINGS

Directory of Open Access Journals (Sweden)

K. A. Starkov

2017-08-01

Full Text Available Purpose. The method of natural concentrated groundings substitution by the set of electrodes taking them into account in the algorithm of electric characteristics calculation for complicated grounding connections of electric installation is offered. An equivalent model as a set of linear electrodes is chosen in accordance with two criteria: leakage resistance and potentials on the ground surface. Methodology. We have applied induced potential method and methods for computing branched electrical circuits with distributed parameters. Results. We have obtained the algorithm for calculating complex non-equipotential grounding connections, which makes it possible to obtain refined values of the potential distribution in the electric stations and substations with outdoor switchgear. Originality. For the first time, we have taking into account the conductivity of natural concentrated grounds by a set of vertical and horizontal electrodes based on equivalent electrical characteristics applied to a two-layer ground. Practical value. The using of the proposed calculation algorithm in the electric grids of JSC «Kharkivoblenergo» made it possible to determine the values of the potential distribution at short circuit in electrical substation taking into account the influence of the conductivity of natural concentrated groundings.

Vehicle to grid: electric vehicles as an energy storage solution

Science.gov (United States)

McGee, Rodney; Waite, Nicholas; Wells, Nicole; Kiamilev, Fouad E.; Kempton, Willett M.

2013-05-01

With increased focus on intermittent renewable energy sources such as wind turbines and photovoltaics, there comes a rising need for large-scale energy storage. The vehicle to grid (V2G) project seeks to meet this need using electric vehicles, whose high power capacity and existing power electronics make them a promising energy storage solution. This paper will describe a charging system designed by the V2G team that facilitates selective charging and backfeeding by electric vehicles. The system consists of a custom circuit board attached to an embedded linux computer that is installed both in the EVSE (electric vehicle supply equipment) and in the power electronics unit of the vehicle. The boards establish an in-band communication link between the EVSE and the vehicle, giving the vehicle internet connectivity and the ability to make intelligent decisions about when to charge and discharge. This is done while maintaining compliance with existing charging protocols (SAEJ1772, IEC62196) and compatibility with standard "nonintelligent" cars and chargers. Through this system, the vehicles in a test fleet have been able to successfully serve as portable temporary grid storage, which has implications for regulating the electrical grid, providing emergency power, or supplying power to forward military bases.

Past and present energy societies. How energy connects politics, technologies and cultures

Energy Technology Data Exchange (ETDEWEB)

Moellers, Nina; Zachmann, Karin (eds.)

2012-07-01

Abundant, salutary, problematic - energy makes history. As a symbol, resource and consumer good, it shapes technologies, politics, societies and cultural world views. Focussing on a range of energy types, from electricity and oil to bioenergy, this volume analyzes the social, cultural and political concepts and discourses of energy and their implementation and materialization within technical systems, applications, media representations and consumer practice. By examining and connecting production, mediation and consumption aspects from an international and interdisciplinary perspective, the book offers an innovative view on how energy is imagined, discussed, staged and used.

Retailing residential electricity : A concept that makes sense?

International Nuclear Information System (INIS)

MacDonald, C.

2003-07-01

A heated debate centres around the deregulation of the electricity industry and the retailing of residential electricity. An assessment of the current situation in the industry was provided in this paper to provide a basis for discussion. The experience gained both in Alberta and Texas in residential retail was examined. The main issue of concern is whether residential customers will benefit from deregulation of the electricity sector. The Retail Energy Deregulation (RED) Index provides a benchmark for those jurisdictions considering the residential options. Deregulation has not led to significant benefits to residential customers in most jurisdictions. The electricity industry will always require a central dispatch/market process that will have to designed, governed, regulated, modified regularly. The benefits to residential consumers are not expected for a very long time. Standard market design is an issue that will require attention. refs., 7 figs

ASP - Grid connections of large power generating units; ASP - Anslutning av stoerre produktionsanlaeggningar till elnaetet

Energy Technology Data Exchange (ETDEWEB)

Larsson, Aake; Larsson, Richard [Vattenfall Power Consultants, Stockholm (Sweden)

2006-12-15

Grid connections of large power generating units normally require more detailed studies compared to small single units. The required R and D-level depends on the specific characteristics of the production units and the connecting grid. An inquiry for a grid connection will raise questions for the grid owner regarding transmission capability, losses, fault currents, relay protection, dynamic stability etc. Then only a few larger wind farms have been built, the experiences from these types of grid connections are limited and for that reason it can be difficult to identify issues appropriate for further studies. To ensure that electric power generating units do not have unacceptable impact on the grid, directions from the Swedish TSO (Svenska Kraftnaet) have been stated. The directions deal, for example, with power generation in specific ranges of voltage level and frequency and the possibility to remain connected to the grid when different faults occur. The requirements and the consequences of these directions are illustrated. There are three main issues that should be considered: Influence on the power flow from generating units regarding voltage level, currents, losses etc.; Different types of electric systems in generating units contribute to different levels of fault currents. For that reason the resulting fault current levels have to be studied; It is required that generating units should remain connected to the grid at different modes of operation and faults. These modes have to be verified. Load flow and dynamic studies normally demand computer models. Comprehensive models, for instance of wind farms, can bee difficult to design and normally large computer capacity is required. Therefore simplified methods to perform relevant studies are described. How to model an electric power generating unit regarding fault currents and dynamic stability is described. An inquiry for a grid connection normally brings about a discussion concerning administration. To make it

Connecting plug-in vehicles with green electricity through consumer demand

Science.gov (United States)

Axsen, Jonn; Kurani, Kenneth S.

2013-03-01

The environmental benefits of plug-in electric vehicles (PEVs) increase if the vehicles are powered by electricity from ‘green’ sources such as solar, wind or small-scale hydroelectricity. Here, we explore the potential to build a market that pairs consumer purchases of PEVs with purchases of green electricity. We implement a web-based survey with three US samples defined by vehicle purchases: conventional new vehicle buyers (n = 1064), hybrid vehicle buyers (n = 364) and PEV buyers (n = 74). Respondents state their interest in a PEV as their next vehicle, in purchasing green electricity in one of three ways, i.e., monthly subscription, two-year lease or solar panel purchase, and in combining the two products. Although we find that a link between PEVs and green electricity is not presently strong in the consciousness of most consumers, the combination is attractive to some consumers when presented. Across all three respondent segments, pairing a PEV with a green electricity program increased interest in PEVs—with a 23% demand increase among buyers of conventional vehicles. Overall, about one-third of respondents presently value the combination of a PEV with green electricity; the proportion is much higher among previous HEV and PEV buyers. Respondents’ reported motives for interest in both products and their combination include financial savings (particularly among conventional buyers), concerns about air pollution and the environment, and interest in new technology (particularly among PEV buyers). The results provide guidance regarding policy and marketing strategies to advance PEVs and green electricity demand.

Connecting plug-in vehicles with green electricity through consumer demand

International Nuclear Information System (INIS)

Axsen, Jonn; Kurani, Kenneth S

2013-01-01

The environmental benefits of plug-in electric vehicles (PEVs) increase if the vehicles are powered by electricity from ‘green’ sources such as solar, wind or small-scale hydroelectricity. Here, we explore the potential to build a market that pairs consumer purchases of PEVs with purchases of green electricity. We implement a web-based survey with three US samples defined by vehicle purchases: conventional new vehicle buyers (n = 1064), hybrid vehicle buyers (n = 364) and PEV buyers (n = 74). Respondents state their interest in a PEV as their next vehicle, in purchasing green electricity in one of three ways, i.e., monthly subscription, two-year lease or solar panel purchase, and in combining the two products. Although we find that a link between PEVs and green electricity is not presently strong in the consciousness of most consumers, the combination is attractive to some consumers when presented. Across all three respondent segments, pairing a PEV with a green electricity program increased interest in PEVs—with a 23% demand increase among buyers of conventional vehicles. Overall, about one-third of respondents presently value the combination of a PEV with green electricity; the proportion is much higher among previous HEV and PEV buyers. Respondents’ reported motives for interest in both products and their combination include financial savings (particularly among conventional buyers), concerns about air pollution and the environment, and interest in new technology (particularly among PEV buyers). The results provide guidance regarding policy and marketing strategies to advance PEVs and green electricity demand. (letter)

Electricity from biomass in the Netherlands

International Nuclear Information System (INIS)

Van Beuge, M.J.J.; Sillevis Smit, E.T.

2004-01-01

In the past decade, the international community has ta-ken various measures towards achieving a more sustainable energy supply and a reduction of greenhouse gas emissions, among which the conclusion of the Kyoto protocol. Both the European Union and The Netherlands regard the large scale use of biomass for the production of electricity as an important instrument towards achieving the aforementioned policy goals. In this regard the European Union introduced the Renewables Directive, the implementation of which in The Netherlands has recently been completed. In connection with the above, The Netherlands' Minister for Economic Affairs recently published the Biomass Action Plan, aimed at increasing - in the short term - energy production, in particular electricity production, from biomass. This article provides insight into the outlines of the legal framework that is relevant for the production of electricity from biomass in The Netherlands. Following a brief introduction to the relationship between bio energy and biomass, as well as a short introduction to the most important ways in which biomass contributes to the production of electricity in The Netherlands, the article sketches the contours of the European and Dutch policies and related legislation regarding the production of electricity from biomass. In particular, this article describes the Dutch legislation aimed at subsidising and thus promoting the production of electricity from biomass, as well as the requirements with which electricity production installations making use of biomass must comply for an environmental and/or waste perspective [nl

Economic aspects of grid connected solar electricity generation

International Nuclear Information System (INIS)

Pharabod, F.

1993-01-01

Experience gained with available solar thermal technologies enlighten on options for research and development on solar electricity generation. The proposed analysis of new solar technologies concerns market, costs and profit viewpoint: - Systems under development have to fit with consumers' needs and utilities' specifications, technology is not the only item to study. - Expense headings depend on technological options and operation procedures such as size of the plant, solar only or hybrid concept. - Anticipation of revenues highly depends on direct insolation quality and on local conditions for introducing the electric power generated into the network: daily direct insolation measurements and annual local load curve are prerequisite data. Strategic advantages regarding environment and sustainable development are to be pointed out, specially in industrialized countries or for projects including financing institutions. As far as generating electric power on the grid is a major challenge in the development of a number of countries in the sun belt, cooperation between industrialized and developing countries, under the auspices of international organization, has to be promoted. (Author) 12 refs

An econometric study of illegal electricity connections in the urban favelas of Belo Horizonte, Brazil

International Nuclear Information System (INIS)

Mimmi, Luisa M.; Ecer, Sencer

2010-01-01

The data from the project 'Conviver,' launched in 2006 in Belo Horizonte (Brazil), provides a unique opportunity to study illegal electricity connections. Based on an original dataset of 15,279 low-income households, this paper studies the incidence and determinants of illegality in the context of low-income urban favelas. The probability of engaging in illegal behavior is explained not just by low income, but by a combination of concurring factors: sub-standard energy provision and equipment; inefficient/incorrect use of domestic electric appliances and running an informal in-house business. These recurrent issues in the urban favelas aggravate a sense of exclusion from growth, which is generally recognized as a trigger of illegality. The impact of energy demand on energy-related illegality is carefully analyzed, and different empirical strategies adopted to circumvent some simultaneity problem between both decision processes. The effectiveness of consumption-based energy subsidies is also explored. In spite of some contrary arguments in the literature, in the context of peri-urban slums, such measures may exert a positive impact in mitigating illegal access and use of energy. Effectiveness will be enhanced by accompanying measures such as: perceivable improvements of equipment, metering and maintenance, promotion of beneficiaries' awareness of energy usage, and energy-saving behaviors.

An econometric study of illegal electricity connections in the urban favelas of Belo Horizonte, Brazil

Energy Technology Data Exchange (ETDEWEB)

Mimmi, Luisa M. [Global Partnership on Output-Based Aid (GPOBA), World Bank (United States); Ecer, Sencer [LECG, Georgetown University Public Policy Institute, Washington, DC (United States)

2010-09-15

The data from the project Conviver, launched in 2006 in Belo Horizonte (Brazil), provides a unique opportunity to study illegal electricity connections. Based on an original dataset of 15,279 low-income households, this paper studies the incidence and determinants of illegality in the context of low-income urban favelas. The probability of engaging in illegal behavior is explained not just by low income, but by a combination of concurring factors: sub-standard energy provision and equipment; inefficient/incorrect use of domestic electric appliances and running an informal in-house business. These recurrent issues in the urban favelas aggravate a sense of exclusion from growth, which is generally recognized as a trigger of illegality. The impact of energy demand on energy-related illegality is carefully analyzed, and different empirical strategies adopted to circumvent some simultaneity problem between both decision processes. The effectiveness of consumption-based energy subsidies is also explored. In spite of some contrary arguments in the literature, in the context of peri-urban slums, such measures may exert a positive impact in mitigating illegal access and use of energy. Effectiveness will be enhanced by accompanying measures such as: perceivable improvements of equipment, metering and maintenance, promotion of beneficiaries' awareness of energy usage, and energy-saving behaviors. (author)

Regulatory Guide 1.131: Qualification tests of electric cables, field splices, and connections for light-water-cooled nuclear power plants

International Nuclear Information System (INIS)

Anon.

1992-01-01

Criterion III, ''Design Control,'' of Appendix B, ''Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plant,'' to 10 CFR Part 50, ''Licensing of Production and Utilization Facilities,'' requires that, where a test program is used to verify the adequacy of a specific design feature, it include suitable qualification testing of a prototype unit under the most adverse design conditions. This regulatory guide describes a method acceptable to the NRC staff for complying with the Commission's regulations with regard to qualification testing of electric cables, field splices, and connections for service in light-water-cooled nuclear power plants to ensure that the cables, field splices, and connections can perform their safety-related functions. The fire test provisions of this guide do not apply to qualification for an installed configuration

Competitiveness of grid-connected solar electricity in Sweden - as seen from the perspective of the utilities and the net owners; Konkurrenskraft foer naetansluten solel i Sverige - sett ur kraftfoeretagens och naetaegarnas perspektiv

Energy Technology Data Exchange (ETDEWEB)

Carlstedt, Nils-Eric [Vattenfall Power Consultant AB, Stockholm (Sweden); Karlsson, Bjoern; Kjellsson, Elisabeth; Samuelsson, Olof [Faculty of Engineering (LTH), Lund University, Lund (Sweden); Neij, Lena [International Institute for Industrial Environmental Economics, Lund University, Lund (Sweden)

2006-12-15

The objective of this report was to analyse the competitiveness of grid-connected solar power in Sweden - and specifically the competitiveness for energy companies and net owners. In theory, solar power could to a large extent fulfil the electricity demand in Sweden, especially in the summer. However, the high cost of solar cells is a major barrier to implementation. Future technology development and increased efficiency could, however, lead to important cost reductions. The question is if such expected cost reductions would make grid-connected solar power a preferable investment option for energy companies and an interesting alternative for the net owners. The results of the study show that solar power will not be a competitive alternative for the energy companies in Sweden, not in 2020 and probably not in 2050. Other alternatives such as new investments in wind turbines and bio-mass based technology options will be producing electricity at a lower cost. Moreover, solar power will have an unfavourable production profile, generating power in the summertime when less needed. However, by using the reservoirs of the hydro power systems in Sweden as storage capacity, approximately 5 TWh solar power could be allowed in the Swedish electricity system. The results of the study indicate that solar power could have a positive effect on the electricity distribution system since distributed generation will result in lower losses in the system. Moreover, solar power will be produced during daytime when the electricity demand will peak. One of the main challenges for the net owners would be to design the net in such a way that the net and the solar cells could work together in the best possible way. Another challenge would be the high cost for connecting the solar cells to the grid; this cost needs to be reduced. Looking instead at the house-owners as possible investors, solar cells appear as a much more attractive alternative for the future, the value of the solar power is

Industry consultation on grid connection of small PV systems

Energy Technology Data Exchange (ETDEWEB)

Knight, J.; Thorneycroft, J.; Cotterell, M.; Gambro, S.

2000-07-01

This report presents the results of consultation within the PV industry and the electricity supply industry concerning guidelines for the connection of small PV systems to the electricity network. (author)

Study of electrical and thermal characteristics of inverters for grid-connected photovoltaic systems; Estudo de caracteristicas eletricas e termicas de inversores para sistemas fotovoltaicos conectados a rede

Energy Technology Data Exchange (ETDEWEB)

Rampinelli, Giuliano Arns

2010-12-15

Grid-connected photovoltaic systems directly convert solar energy into electrical energy delivering to the distribution grid a clean and renewable energy. These systems are basically formed by an array of photovoltaic modules and inverters. The inverters are responsible for converting direct current to alternating current. A study of electrical and thermal characteristics of inverters used in grid-connected photovoltaic systems from a theoretical and experimental analysis. The inverters tests were carried out in two stages: the first stage was performed at Solar Energy Lab. of the Federal University of Rio Grande do Sul (UFRGS), Brazil, where it was used a 4,8 kW{sub p} grid-connected photovoltaic system and ten inverters of different manufacturers. The inverters electrical characteristics measured and analyzed were: direct current to alternating current conversion efficiency, maximum power point tracker efficiency, power factor and harmonic distortion in current and voltage. Inverters thermal testing was also conducted and its results are presented ana analyzed. The second stage of the experimental tests was performed at Photovoltaic Solar Energy Lab. at CIEMAT in Spain. It was used 3 kW{sub p} photovoltaic system and seven inverters of different manufacturers. The inverters are single-phase, up to 5 kW and different topologies (high frequency transformer, low frequency transformer and transformerless). The influence of DC voltage input in the behavior of DC to AC conversion efficiency and power factor was analyzed. The results of the tests allowed the development of mathematical models that describe the electrical and thermal behavior of the inverters. The proposed mathematical models were inserted into computer simulation software developed at UFRGS named FVConect. The evolution of the simulation results compared to the experimental results validates the proposed models. The analysis of the behavior of the inverters improves the understanding of the operating os

International cost relations in electric power generation

International Nuclear Information System (INIS)

Schmitt, D.; Duengen, H.; Wilhelm, M.

1986-01-01

In spite of the fact that analyses of the cost of electric power generation as the result of international comparative evaluations are indisputably relevant, problems pending in connection with the costs of representative power plant technologies are of the methodological bind. German authors have hitherto also been failing to clear up and consider all aspects connected with the problems of data acquisition and the adequate interpretation of results. The analysis presented by the paper abstracted therefore aims at the following: 1) Systematization of the different categories of cost relevant in connection with international comparative evaluation. Classification into different categories of decision making and development of standards meeting the requirements of international comparative evaluation. 2) Calculation of relevant average financial costs of Western German, America and French fossil-fuel and nuclear power plants by means of adequate calculation models, that is the assessment of costs with regard to countries and power plant technologies which are relevant to the Federal Republic of Germany. 3) Analysis of the resulting differences and determinantal interpretation. (orig./UA) [de

14 CFR 27.1365 - Electric cables.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Electric cables. 27.1365 Section 27.1365... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Electrical Systems and Equipment § 27.1365 Electric cables. (a) Each electric connecting cable must be of adequate capacity. (b) Each cable that would overheat...

Nuclear Power as an Option in Electrical Generation Planning for Small Economy and Electricity Grid

International Nuclear Information System (INIS)

Tomsic, Z.

2012-01-01

Implementing a NPP in countries with relatively small total GDP (small economy) and usually with small electricity grid face two major problems and constrains: the ability to obtain the considerable financial resources required on reasonable terms and to connect large NPP to small electricity grid. Nuclear generation financing in developing countries involves complex issues that need to be fully understood and dealt with by all the parties involved. The main topics covered by paper will be the: special circumstances related to the financing of NPP, costs and economic feasibility of NPP, conventional approaches for financing power generation projects in developing countries, alternative approaches for mobilizing financial resources. The safe and economic operation of a nuclear power plant (NPP) requires the plant to be connected to an electrical grid system that has adequate capacity for exporting the power from the NPP, and for providing a reliable electrical supply to the NPP for safe start-up, operation and normal or emergency shut-down of the plant. Connection of any large new power plant to the electrical grid system in a country may require significant modification and strengthening of the grid system, but for NPPs there may be added requirements to the structure of the grid system and the way it is controlled and maintained to ensure adequate reliability. Paper shows the comparative assesment of differrent base load technologies as an option in electrical generation planning for small economy and electricity grid.(author).

Optimising reverse logistics network to support policy-making in the case of Electrical and Electronic Equipment.

Science.gov (United States)

Achillas, Ch; Vlachokostas, Ch; Aidonis, D; Moussiopoulos, N; Iakovou, E; Banias, G

2010-12-01

Due to the rapid growth of Waste Electrical and Electronic Equipment (WEEE) volumes, as well as the hazardousness of obsolete electr(on)ic goods, this type of waste is now recognised as a priority stream in the developed countries. Policy-making related to the development of the necessary infrastructure and the coordination of all relevant stakeholders is crucial for the efficient management and viability of individually collected waste. This paper presents a decision support tool for policy-makers and regulators to optimise electr(on)ic products' reverse logistics network. To that effect, a Mixed Integer Linear Programming mathematical model is formulated taking into account existing infrastructure of collection points and recycling facilities. The applicability of the developed model is demonstrated employing a real-world case study for the Region of Central Macedonia, Greece. The paper concludes with presenting relevant obtained managerial insights. Copyright © 2010 Elsevier Ltd. All rights reserved.

Development of electrical connections around the Mediterranean Basin

International Nuclear Information System (INIS)

Persoz, H.; Nogaret, E.

1992-01-01

Interconnections of electrical networks bring a great many benefits, which explains why European countries did this as early as the fifties. More recently, the nations to the south and east of the Mediterranean basin have started interconnecting, and cross-sea links are also planned, which will put all of the countries in contact with each other. The main projects in this direction concern the establishment of undersea links between Spain and Morocco and between Italy and Tunisia; beefing up the interconnections between the North African countries; and developing ties in the Near East, from Egypt to Turkey. As this system comes into being, a computerized management system will have to be installed too, to avoid operational difficulties; so the overall consistency of the various projects will have to be verified by studies conducted at the regional level. This clearly shows that cooperation is indispensable among all the countries concerned. Medelec, a liaison committee of Mediterranean electrical producer association, was created to undertake common actions in this sense. It is certain that the creation of an interconnected electrical network around the Mediterranean will go a long way toward strengthening exchanges and cooperation among these nations. 1 fig., 5 tabs

Electric dipole moments reconsidered

International Nuclear Information System (INIS)

Rupertsberger, H.

1989-01-01

The electric dipole moments of elementary particles, atoms, molecules and their connection to the electric susceptibility are discussed for stationary states. Assuming rotational invariance it is emphasized that for such states only in the case of a parity and time reversal violating interaction the considered particles can obtain a nonvanishing expectation value for the electric dipole moment. 1 fig., 13 refs. (Author)

Making the Earth to Life Connection Using Climate Change

Science.gov (United States)

Haine, D. B.; Berbeco, M.

2016-12-01

From ocean acidification to changes in air quality to shifts in the range of disease vectors, there are many opportunities for educators to make the earth science to life science connection by incorporating the impacts of climate change on organisms and entire ecosystems and by describing how living organisms impact climate. NCSE's study in Science found that 86% of life science teachers are teaching climate, but few admit they have any formal climate science training. This session will introduce activities we developed that utilize the 2014 National Climate Assessment, data visualizations, technology tools and models to allow students to explore the evidence that climate change is impacting life. Translating the NCA into classroom activities is an approach that becomes more pertinent with the advent of the Next Generation Science Standards (NGSS). Using the NCA and the NGSS we demonstrate strategies for weaving the concept of climate change into an already packed life science curriculum by enhancing rather than displacing content and ultimately promoting integration of science and engineering practices into instruction. Since the fall of 2014 we have engaged approximately 200 K-12 educators at local, state, regional and national teacher professional development events. Here we will summarize what we have learned from science teachers about how they address life science impacts of climate change and we will summarize evaluation data to inform future efforts to engage life science educators in light of the recent USGCRP Climate and Health Assessment and the upcoming 4th National Climate Assessment.

A Study of the Properties of Electrical Insulation Oils and of the Components of Natural Oils

Directory of Open Access Journals (Sweden)

Milan Spohner

2012-01-01

Full Text Available This paper presents a study of the electrical and non-electrical properties of insulating oils. For the correct choice of an electrical insulation oil, it is necessary to know its density, dynamic viscosity, dielectric constant, loss number and conductivity, and the effects of various exposure factors. This paper deals with mathematical and physical principles needed for studying and making correct measurements of the dynamic viscosity, density and electrical properties of insulation oils. Rheological properties were measured using an A&D SV-10 vibratory viscometer, and analytical balance with density determination kit, which operates on the principle of Archimedes’ law. Dielectric properties were measured using a LCR meter Agilent 4980A with connected with the Agilent 16452A test fixture for dielectric liquids.

Energy efficiency design strategies for buildings with grid-connected photovoltaic systems

Science.gov (United States)

Yimprayoon, Chanikarn

The building sector in the United States represents more than 40% of the nation's energy consumption. Energy efficiency design strategies and renewable energy are keys to reduce building energy demand. Grid-connected photovoltaic (PV) systems installed on buildings have been the fastest growing market in the PV industry. This growth poses challenges for buildings qualified to serve in this market sector. Electricity produced from solar energy is intermittent. Matching building electricity demand with PV output can increase PV system efficiency. Through experimental methods and case studies, computer simulations were used to investigate the priorities of energy efficiency design strategies that decreased electricity demand while producing load profiles matching with unique output profiles from PV. Three building types (residential, commercial, and industrial) of varying sizes and use patterns located in 16 climate zones were modeled according to ASHRAE 90.1 requirements. Buildings were analyzed individually and as a group. Complying with ASHRAE energy standards can reduce annual electricity consumption at least 13%. With energy efficiency design strategies, the reduction could reach up to 65%, making it possible for PV systems to meet reduced demands in residential and industrial buildings. The peak electricity demand reduction could be up to 71% with integration of strategies and PV. Reducing lighting power density was the best single strategy with high overall performances. Combined strategies such as zero energy building are also recommended. Electricity consumption reductions are the sum of the reductions from strategies and PV output. However, peak electricity reductions were less than their sum because they reduced peak at different times. The potential of grid stress reduction is significant. Investment incentives from government and utilities are necessary. The PV system sizes on net metering interconnection should not be limited by legislation existing in

Maximum capacity model of grid-connected multi-wind farms considering static security constraints in electrical grids

International Nuclear Information System (INIS)

Zhou, W; Oodo, S O; He, H; Qiu, G Y

2013-01-01

An increasing interest in wind energy and the advance of related technologies have increased the connection of wind power generation into electrical grids. This paper proposes an optimization model for determining the maximum capacity of wind farms in a power system. In this model, generator power output limits, voltage limits and thermal limits of branches in the grid system were considered in order to limit the steady-state security influence of wind generators on the power system. The optimization model was solved by a nonlinear primal-dual interior-point method. An IEEE-30 bus system with two wind farms was tested through simulation studies, plus an analysis conducted to verify the effectiveness of the proposed model. The results indicated that the model is efficient and reasonable.

Maximum capacity model of grid-connected multi-wind farms considering static security constraints in electrical grids

Science.gov (United States)

Zhou, W.; Qiu, G. Y.; Oodo, S. O.; He, H.

2013-03-01

An increasing interest in wind energy and the advance of related technologies have increased the connection of wind power generation into electrical grids. This paper proposes an optimization model for determining the maximum capacity of wind farms in a power system. In this model, generator power output limits, voltage limits and thermal limits of branches in the grid system were considered in order to limit the steady-state security influence of wind generators on the power system. The optimization model was solved by a nonlinear primal-dual interior-point method. An IEEE-30 bus system with two wind farms was tested through simulation studies, plus an analysis conducted to verify the effectiveness of the proposed model. The results indicated that the model is efficient and reasonable.

Small Wind Electric Systems: A North Carolina Consumer's Guide

Energy Technology Data Exchange (ETDEWEB)

2005-03-01

Small Wind Electric Systems: A North Carolina Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

IEEE Std 383-1974: IEEE standard for type test of Class IE electric cables, field splices, and connections for nuclear power generating stations

International Nuclear Information System (INIS)

Anon.

1992-01-01

This standard provides direction for establishing type tests which may be used in qualifying Class 1E electric cables, field splices, and other connections for service in nuclear power generating stations. General guidelines for qualifications are given in IEEE Std 323-1974, Standard for Qualifying Class IE Electric Equipment for Nuclear Power Generating Stations. Categories of cables covered are those used for power control and instrumentation services. Though intended primarily to pertain to cable for field installation, this guide may also be used for the qualification of internal wiring of manufactured devices. This guide does not cover cables for service within the reactor vessel

Electric circuits and signals

CERN Document Server

Sabah, Nassir H

2007-01-01

Circuit Variables and Elements Overview Learning Objectives Electric Current Voltage Electric Power and Energy Assigned Positive Directions Active and Passive Circuit Elements Voltage and Current Sources The Resistor The Capacitor The Inductor Concluding Remarks Summary of Main Concepts and Results Learning Outcomes Supplementary Topics on CD Problems and Exercises Basic Circuit Connections and Laws Overview Learning Objectives Circuit Terminology Kirchhoff's Laws Voltage Division and Series Connection of Resistors Current Division and Parallel Connection of Resistors D-Y Transformation Source Equivalence and Transformation Reduced-Voltage Supply Summary of Main Concepts and Results Learning Outcomes Supplementary Topics and Examples on CD Problems and Exercises Basic Analysis of Resistive Circuits Overview Learning Objectives Number of Independent Circuit Equations Node-Voltage Analysis Special Considerations in Node-Voltage Analysis Mesh-Current Analysis Special Conside...

Power take-off analysis for diagonally connected MHD channels

International Nuclear Information System (INIS)

Pan, Y.C.; Doss, E.D.

1980-01-01

The electrical loading of the power take-off region of diagonally connected MHD channels is investigated by a two-dimensional model. The study examines the loading schemes typical of those proposed for the U-25 and U-25 Bypass channels. The model is applicable for the following four cases: (1) connection with diodes only, (2) connection with diodes and equal resistors, (3) connection with diodes and variable resistances to obtain a given current distribution, and (4) connection with diodes and variable resistors under changing load. The analysis is applicable for the power take-off regions of single or multiple-output systems. The general behaviors of the current and the potential distributions in all four cases are discussed. The analytical results are in good agreement with the experimental data. It is found possible to design the electrical circuit of the channel in the take-off region so as to achieve a fairly even load current output under changing total load current

A Method for Using Adjacency Matrices to Analyze the Connections Students Make within and between Concepts: The Case of Linear Algebra

Science.gov (United States)

Selinski, Natalie E.; Rasmussen, Chris; Wawro, Megan; Zandieh, Michelle

2014-01-01

The central goals of most introductory linear algebra courses are to develop students' proficiency with matrix techniques, to promote their understanding of key concepts, and to increase their ability to make connections between concepts. In this article, we present an innovative method using adjacency matrices to analyze students' interpretation…

Fuzzy-Estimation Control for Improvement Microwave Connection for Iraq Electrical Grid

Science.gov (United States)

Hoomod, Haider K.; Radi, Mohammed

2018-05-01

The demand for broadband wireless services is increasing day by day (as internet or radio broadcast and TV etc.) for this reason and optimal exploiting for this bandwidth may be other reasons indeed be there is problem in the communication channels. it’s necessary that exploiting the good part form this bandwidth. In this paper, we propose to use estimation technique for estimate channel availability in that moment and next one to know the error in the bandwidth channel for controlling the possibility data transferring through the channel. The proposed estimation based on the combination of the least Minimum square (LMS), Standard Kalman filter, and Modified Kalman filter. The error estimation in channel use as control parameter in fuzzy rules to adjusted the rate and size sending data through the network channel, and rearrangement the priorities of the buffered data (workstation control parameters, Texts, phone call, images, and camera video) for the worst cases of error in channel. The propose system is designed to management data communications through the channels connect among the Iraqi electrical grid stations. The proposed results show that the modified Kalman filter have a best result in time and noise estimation (0.1109 for 5% noise estimation to 0.3211 for 90% noise estimation) and the packets loss rate is reduced with ratio from (35% to 385%).

The application of financial options theory to electric utility decision making in integrated resource planning and maintenance shutdowns

International Nuclear Information System (INIS)

Felder, F.

1995-01-01

Increased competition in wholesale power generation will allow electric utilities to use financial models to improve their decision making. This competition will result in the creation of electricity spot, futures, and forward markets, which will provide necessary information for utility executives to used advance financial tools, such as random walk models and options theory. These models will allow executives to place a value on risk. Once this value is known, executives can determine how best to manage that risk, whether by entering into financial transactions, adjusting their operational and planning decisions, or both

Energy-efficient three-phase bidirectional converter for grid-connected storage applications

International Nuclear Information System (INIS)

Colmenar-Santos, Antonio; Linares-Mena, Ana-Rosa; Velázquez, Jesús Fernández; Borge-Diez, David

2016-01-01

Highlights: • Storage control system developed based on AC DC three phase bidirectional converter. • Bidirectional AC DC converter for storage integration into distribution grids. • Efficiencies over 98% for values over 30% of the bidirectional converter rated power. • Sensitivity analysis of the parameters set by the transmission system operator. • Low-cost option for control and integration of new grid-connected storage systems. - Abstract: Grid connected energy storage systems are expected to play an essential role in the development of Smart Grids, providing, among other benefits, ancillary services to power grids. It is therefore crucial to design and develop control and conversion systems that represent the key instrument where intelligence for decision-making is applied, in order to validate and ensure its optimal operation as part and parcel of the electrical system. The present research describes the design and development of a battery energy storage system based on an AC-DC three-phase bidirectional converter capable of operating either in charge mode to store electrical energy, or in discharge mode to supply load demands. The design is modelled with MATLAB® Simulink® environment in order to evaluate the performance during load variations. Moreover, the assessment is complemented by a global sensitivity analysis for variations in the operating parameters set by the transmission system operator. The effectiveness of the simulation is confirmed by implementing the system and carrying out grid connection tests, obtaining efficiencies over 98% for values over the 30% of the bidirectional converter rated power.

Green power. Renewable electricity purchasing by Leicester City Council

International Nuclear Information System (INIS)

2000-05-01

This case study describes the use of renewable energy by Leicester City Council in the East Midlands. The Council, which has a long-term commitment to sustainable energy and the environment, employs over 14,000 people. A contract was first negotiated with East Midlands Electricity (now PowerGen) to supply the Council's New Walk Centre with green electricity in 1995. Some of the green energy is supplied by the Milford Mill hydroelectric plant. Use of building energy monitoring systems (BEMSs) and other good practice has allowed the Council to achieve a 20% saving in its electricity bill. The Council has also negotiated contracts to supply two smaller sites (a recycling facility called Planet Works and the city's Energy Efficiency centre) with green electricity generated by Beacon Energy, a small renewable energy company which operates two 25 kW wind turbines and two 3 kW arrays of photovoltaic cells at a site some 15 miles from Leicester. The exemption given to renewable energy from the climate change levy makes these schemes even more economic; a worked example is provided to demonstrate the impact of the climate change levy on electricity costs at the New Walk Centre. Six steps to follow when seeking to connect to green electricity are advised

Modeling Of Components Of A Photovoltaic System With Voltage Inverter For Connection To The Electrical Grid

International Nuclear Information System (INIS)

Ferreira, Andreza C.; Blasques, Luis C. M.; Galhardo, Marcos A. B.; Pinho, João T.

2017-01-01

This paper describes the modeling of the electrical equipment and control mechanisms used in the power conditioning system of a grid-connected photovoltaic system (GCPVS), such as the photovoltaic generator, the DC/DC converter, the voltage inverter with PWM control, its output filter, as well as the converter controls and their functionalities, and the interconnection of the system with the distribution grid and load. In addition to the modeling of the grid-tie inverter, the main equipment of the power conditioning system, this paper describes the synchronization form of the photovoltaic (PV) generation with the electricity distribution grid, considering the power injection control method, the maximum power point tracking technique for maximizing the energy supplied by the photovoltaic generator, and the complete topology of the proposed PV system. The main objective is to provide a computational model capable of simulating the behavior of the GCPVS elements, varying the climatic conditions and the power demand on the AC side, presenting consistent results for different operating conditions, such as variations of climatic parameters (solar irradiance, wind speed, and ambient temperature) and load. In these cases, it is possible to evaluate the behavior of the system, sometimes supplying both the active and reactive power of the load, according to the need. (author)

Intelligent Decision-Making System with Green Pervasive Computing for Renewable Energy Business in Electricity Markets on Smart Grid

Directory of Open Access Journals (Sweden)

Park JongHyuk

2009-01-01

Full Text Available This paper is about the intelligent decision-making system for the smart grid based electricity market which requires distributed decision making on the competitive environments composed of many players and components. It is very important to consider the renewable energy and emission problem which are expected to be monitored by wireless communication networks. It is very difficult to predict renewable energy outputs and emission prices over time horizon, so it could be helpful to catch up those data on real time basis using many different kinds of communication infrastructures. On this backgrounds this paper provides an algorithm to make an optimal decision considering above factors.

Description of the electric power and energy trade in Finland

International Nuclear Information System (INIS)

Komulainen, K.

1992-01-01

The Finnish State has traditionally controlled the import of electricity, larger related investments and pricing. Lately, a market orientated economic policy has influenced energy policy and the amount of state control has gradually decreased. Decisions have yet to be made with regard to the fifth nuclear power reactor. The paper deals briefly with the subjects of the electric power, natural gas and oil markets. Finland's transmission network has connections to the former Russia and the Baltic countries. According to agreements within the European Community, Finland must now make changes in its electric power supply structure. Competition will be encouraged and monopolies discouraged. Pricing shall be transparent, and power plants must present written documentation for their management system, price regulations etc. A law must be passed to legitimate trade across the country's borders. Emphasis will be laid on energy conservation and energy research and consultant services. It is claimed that Finland's level of technology in this area lives up to international standards. (AB)

Impact of Rural Grid-Connected Photovoltaic Generation Systems on Power Quality

Directory of Open Access Journals (Sweden)

Rita Pinto

2016-09-01

Full Text Available Photovoltaic (PV generation systems have been increasingly used to generate electricity from renewable sources, attracting a growing interest. Recently, grid connected PV micro-generation facilities in individual homes have increased due to governmental policies as well as greater attention by industry. As low voltage (LV distribution systems were built to make energy flow in one direction, the power feed-in of PV generation in rural low-voltage grids can influence power quality (PQ as well as facility operation and reliability. This paper presents results on PQ analysis of a real PV generation facility connected to a rural low-voltage grid. Voltage fluctuations and voltage harmonic contents were observed. Statistical analysis shows a negative impact on PQ produced by this PV facility and also that only a small fraction of the energy available during a sunny day is converted, provoking losses of revenue and forcing the converter to work in an undesirable operating mode. We discuss the disturbances imposed upon the grid and their outcome regarding technical and economic viability of the PV system, as well as possible solutions. A low-voltage grid strengthening has been suggested and implemented. After that a new PQ analysis shows an improvement in the impact upon PQ, making this facility economically viable.

Customized electric power storage device for inclusion in a collective microgrid

Science.gov (United States)

Robinett, III, Rush D.; Wilson, David G.; Goldsmith, Steven Y.

2016-02-16

An electric power storage device is described herein, wherein the electric power storage device is included in a microgrid. The electric power storage device has at least one of a charge rate, a discharge rate, or a power retention capacity that has been customized for a collective microgrid. The collective microgrid includes at least two connected microgrids. The at least one of the charge rate, the discharge rate, or the power retention capacity of the electric power storage device is computed based at least in part upon specified power source parameters in the at least two connected microgrids and specified load parameters in the at least two connected microgrids.

Online forecasting of electrical load for distributed management of plug-in electric vehicles

OpenAIRE

Basu , Kaustav; Ovalle , Andres; Guo , Baoling; Hably , Ahmad; Bacha , Seddik; Hajar , Khaled

2016-01-01

International audience; The paper aims at making online forecast of electrical load at the MV-LV transformer level. Optimal management of the Plug-in Electric Vehicles (PEV) charging requires the forecast of the electrical load for future hours. The forecasting module needs to be online (i.e update and make forecast for the future hours, every hour). The inputs to the predictor are historical electrical and weather data. Various data driven machine learning algorithms are compared to derive t...

Virtual laboratory of electrical mini-grids with distributed generation

International Nuclear Information System (INIS)

Menezes Ramos, Vanessa; Barros Galhardo, Marcos André; Oliveira Barbosa, Claudomiro Fábio de; Tavares Pinho, João

2015-01-01

This paper presents a computing tool called Virtual Laboratory de Minirredes (Virtual Laboratory of Mini-grids). Using the virtual environment of the developed tool, it is possible to make remote connection/disconnection of switches and loads (resistive, inductive, capacitive and non-linear) at strategic points of the electric mini-grid with hybrid distributed generation systems (solar photovoltaic-diesel). The mini-grid has a length of about 1 km and is installed in the test area of the Grupo de Estudios e Desenvolvimento de Alternativas Exergética (GEDAE) of the Universidade Federal do Pará, located in the city of Belém, Pará, Brazil. The developed tool has communication functions with electric parameters transducers and programmable logic controllers (PLCs). This communication enables the opening and closing of contactors, resulting in different settings for the mini-grid. In addition to that, based on the proposed configuration by the user, the real-time operation status of mini-grid is presented in a graphic interface (for example, monitored electric parameters, distributed generators connected, status of disconnected switches, etc.) and the acquired data is stored. The use of the computing tool also focuses on the construction of a database, in order to obtain knowledge about the mini-grid performance under various conditions that can be set, depending on the operational strategy adopted, based on the choice of the layout, loads and power sources used in the mini-grid. (full text)

Interim Report by Asia International Grid Connection Study Group

Science.gov (United States)

Omatsu, Ryo

2018-01-01

The Asia International Grid Connection Study Group Interim Report examines the feasibility of developing an international grid connection in Japan. The Group has investigated different cases of grid connections in Europe and conducted research on electricity markets in Northeast Asia, and identifies the barriers and challenges for developing an international grid network including Japan. This presentation introduces basic contents of the interim report by the Study Group.

Novel Electrically Small Spherical Electric Dipole Antenna

DEFF Research Database (Denmark)

Kim, Oleksiy S.

2010-01-01

This paper introduces a novel electrically small spherical meander antenna. Horizontal sections of the meander are composed of wire loops, radii of which are chosen so that the whole structure is conformal to a sphere of radius a. To form the meander the loops are connected by wires at a meridian...

Multi-objective stochastic scheduling optimization model for connecting a virtual power plant to wind-photovoltaic-electric vehicles considering uncertainties and demand response

International Nuclear Information System (INIS)

Ju, Liwei; Li, Huanhuan; Zhao, Junwei; Chen, Kangting; Tan, Qingkun; Tan, Zhongfu

2016-01-01

Highlights: • Our research focuses on virtual power plant. • Electric vehicle group and demand response are integrated into virtual power plant. • Stochastic chance constraint planning is applied to overcome uncertainties. • A multi-objective stochastic scheduling model is proposed for virtual power plant. • A three-stage hybrid intelligent solution algorithm is proposed for solving the model. - Abstract: A stochastic chance-constrained planning method is applied to build a multi-objective optimization model for virtual power plant scheduling. Firstly, the implementation cost of demand response is calculated using the system income difference. Secondly, a wind power plant, photovoltaic power, an electric vehicle group and a conventional power plant are aggregated into a virtual power plant. A stochastic scheduling model is proposed for the virtual power plant, considering uncertainties under three objective functions. Thirdly, a three-stage hybrid intelligent solution algorithm is proposed, featuring the particle swarm optimization algorithm, the entropy weight method and the fuzzy satisfaction theory. Finally, the Yunnan distributed power demonstration project in China is utilized for example analysis. Simulation results demonstrate that when considering uncertainties, the system will reduce the grid connection of the wind power plant and photovoltaic power to decrease the power shortage punishment cost. The average reduction of the system power shortage punishment cost and the operation revenue of virtual power plant are 61.5% and 1.76%, respectively, while the average increase of the system abandoned energy cost is 40.4%. The output of the virtual power plant exhibits a reverse distribution with the confidence degree of the uncertainty variable. The proposed algorithm rapidly calculates a global optimal set. The electric vehicle group could provide spinning reserve to ensure stability of the output of the virtual power plant. Demand response could

Applying mathematical finance tools to the competitive Nordic electricity market

International Nuclear Information System (INIS)

Vehvilaeinen, I.

2004-01-01

This thesis models competitive electricity markets using the methods of mathematical finance. Fundamental problems of finance are market price modelling, derivative pricing, and optimal portfolio selection. The same questions arise in competitive electricity markets. The thesis presents an electricity spot price model based on the fundamental stochastic factors that affect electricity prices. The resulting price model has sound economic foundations, is able to explain spot market price movements, and offers a computationally efficient way of simulating spot prices. The thesis shows that the connection between spot prices and electricity forward prices is nontrivial because electricity is a commodity that must be consumed immediately. Consequently, forward prices of different times are based on the supply-demand conditions at those times. This thesis introduces a statistical model that captures the main characteristics of observed forward price movements. The thesis presents the pricing problems relating to the common Nordic electricity derivatives, as well as the pricing relations between electricity derivatives. The special characteristics of electricity make spot electricity market incomplete. The thesis assumes the existence of a risk-neutral martingale measure so that formal pricing results can be obtained. Some concepts introduced in financial markets are directly usable in the electricity markets. The risk management application in this thesis uses a static optimal portfolio selection framework where Monte Carlo simulation provides quantitative results. The application of mathematical finance requires careful consideration of the special characteristics of the electricity markets. Economic theory and reasoning have to be taken into account when constructing financial models in competitive electricity markets. (orig.)

Why the Personal Competencies Matter. Connect: Making Learning Personal

Science.gov (United States)

Redding, Sam

2015-01-01

This issue in the "Connect" series is a field report that discusses how a student's personal competencies--cognitive, metacognitive, motivational, and social/emotional--propel learning and other forms of goal attainment. These personal competencies are personal to the individual in their shape, size, and effect, but they are enhanced by…

Semantic connections: exploring and manipulating connections in smart spaces

NARCIS (Netherlands)

Vlist, van der B.J.J.; Niezen, G.; Hu, J.; Feijs, L.M.G.

2010-01-01

In envisioned smart environments, enabled by ubiquitous computing technologies, electronic objects will be able to interconnect and interoperate. How will users of such smart environments make sense of the connections that are made and the information that is exchanged? This Internet of Things could

How Engineers Make Markets Organizing Electricity System Decarbonization

DEFF Research Database (Denmark)

Jenle, Rasmus Ploug; Pallesen, Trine

2017-01-01

construction process undertaken by scientists at the Technical University of Denmark, this article shows how engineers have approached the task by designing markets as technical control systems. It is demonstrated that EcoGrid has been designed by modeling a retail electricity market on three different...... conceptions of control systems as found in the discipline of control systems engineering. By tracing the origins of EcoGrid, this article documents the governing of electricity consumers through what we here call a synthetic market, i.e. a market artifact devised to attain goals. These findings about...

How Analysts Cognitively “Connect the Dots”

Energy Technology Data Exchange (ETDEWEB)

Bradel, Lauren; Self, Jessica S.; Endert, Alexander; Hossain, Shahriar M.; North, Chris; Ramakrishnan, Naren

2013-06-04

As analysts attempt to make sense of a collection of documents, such as intelligence analysis reports, they may wish to “connect the dots” between pieces of information that may initially seem unrelated. This process of synthesizing information between information requires users to make connections between pairs of documents, creating a conceptual story. We conducted a user study to analyze the process by which users connect pairs of documents and how they spatially arrange information. Users created conceptual stories that connected the dots using organizational strategies that ranged in complexity. We propose taxonomies for cognitive connections and physical structures used when trying to “connect the dots” between two documents. We compared the user-created stories with a data-mining algorithm that constructs chains of documents using co-occurrence metrics. Using the insight gained into the storytelling process, we offer design considerations for the existing data mining algorithm and corresponding tools to combine the power of data mining and the complex cognitive processing of analysts.

Decentralized electricity generation by using photovoltaic grid-connected solar system

International Nuclear Information System (INIS)

Tyutyundziev, N.; Vitanov, P.; Radkov, R.; Grottke, M.

2006-01-01

AcadPV is the first demonstration installation connected permanently to LV grid in Sofia, Bulgaria aiming at assessment of PV efficiencies and cost-effectiveness. A thorough analysis has been carried out in order to select PV system site, supporting construction design and orientation. The PV generator is divided to 3 PV subfields equipped by 3 SUNPOWER inverters connected to 3 separated phases of the grid. The performance of 10kWp PV system has been evaluated during the first year of operation and compared to PV simulation software results

Reliable electricity. The effects of system integration and cooperative measures to make it work

Energy Technology Data Exchange (ETDEWEB)

Hagspiel, Simeon [Koeln Univ. (Germany). Energiewirtschaftliches Inst.; Koeln Univ. (Germany). Dept. of Economics

2017-12-15

We investigate the effects of system integration for reliability of supply in regional electricity systems along with cooperative measures to support it. Specifically, we set up a model to contrast the benefits from integration through statistical balancing (i.e., a positive externality) with the risk of cascading outages (a negative externality). The model is calibrated with a comprehensive dataset comprising 28 European countries on a high spatial and temporal resolution. We find that positive externalities from system integration prevail, and that cooperation is key to meet reliability targets efficiently. To enable efficient solutions in a non-marketed environment, we formulate the problem as a cooperative game and study different rules to allocate the positive and negative effects to individual countries. Strikingly, we find that without a mechanism, the integrated solution is unstable. In contrast, proper transfer payments can be found to make all countries better off in full integration, and the Nucleolus is identified as a particularly promising candidate. The rule could be used as a basis for compensation payments to support the successful integration and cooperation of electricity systems.

Reliable electricity. The effects of system integration and cooperative measures to make it work

International Nuclear Information System (INIS)

Hagspiel, Simeon; Koeln Univ.

2017-01-01

We investigate the effects of system integration for reliability of supply in regional electricity systems along with cooperative measures to support it. Specifically, we set up a model to contrast the benefits from integration through statistical balancing (i.e., a positive externality) with the risk of cascading outages (a negative externality). The model is calibrated with a comprehensive dataset comprising 28 European countries on a high spatial and temporal resolution. We find that positive externalities from system integration prevail, and that cooperation is key to meet reliability targets efficiently. To enable efficient solutions in a non-marketed environment, we formulate the problem as a cooperative game and study different rules to allocate the positive and negative effects to individual countries. Strikingly, we find that without a mechanism, the integrated solution is unstable. In contrast, proper transfer payments can be found to make all countries better off in full integration, and the Nucleolus is identified as a particularly promising candidate. The rule could be used as a basis for compensation payments to support the successful integration and cooperation of electricity systems.

MANAGING THE LOAD SCHEDULE OF THE ADMINISTRATIVE BUILDING TAKING INTO ACCOUNT EMERGING RISKS WHEN CONNECTING THE KINETIC ENERGY STORAGE TO THE POWER SUPPLY SYSTEM

Directory of Open Access Journals (Sweden)

S. Yu. Shevchenko

2017-12-01

Full Text Available Purpose. The purpose of the paper is to analyze load schedules of the administrative building and develop a structural scheme for connecting the kinetic energy storage in the power supply system of this building, which will allow using it as a consumer regulator, as well as a theoretical study of the risks that arise. Methodology. To conduct the research, the theory of designing internal electrical networks of buildings, the theory of plotting electric load graphs, methods of the theory of electromechanical systems and for analyzing the risk system, the T. Saati method of hierarchies were used. Results. The structure of kinetic energy storage (KES connection to the power supply system of the administrative building is developed and the structural diagram of the KES proposed for installation is given, the average daily winter and summer load schedules are presented, a set of groups and subgroups of risks and their influence on the work of the power supply system of the building are connected with the connection of the KES. Originality. For the first time, the application of the kinetic energy storage in the power supply system of the building with the analysis of emerging risks is considered, which makes it possible to improve the reliability of the developed system and the efficiency of load regulation. Practical value. The application of the proposed scheme will make it possible to use administrative buildings as load regulators of the external power supply system, and also effectively manage the load in the internal power supply system of the building.

Low Voltage Ride-Through Capability of a Single-Stage Single-Phase Photovoltaic System Connected to the Low-Voltage Grid

DEFF Research Database (Denmark)

Yang, Yongheng; Blaabjerg, Frede

2013-01-01

The progressively growing of single-phase photovoltaic (PV) systems makes the Distribution System Operators (DSO) to update or revise the existing grid codes in order to guarantee the availability, quality and reliability of the electrical system. It is expected that the future PV systems connected...... to the low-voltage grid will be more active with functionalities of low voltage ride-through (LVRT) and the grid support capability, which is not the case today. In this paper, the operation principle is demonstrated for a single-phase grid-connected PV system in low voltage ride through operation in order...... to map future challenges. The system is verified by simulations and experiments. Test results show that the proposed power control method is effective and the single-phase PV inverters connected to low-voltage networks are ready to provide grid support and ride-through voltage fault capability...

Connected Traveler

Energy Technology Data Exchange (ETDEWEB)

2016-06-01

The Connected Traveler framework seeks to boost the energy efficiency of personal travel and the overall transportation system by maximizing the accuracy of predicted traveler behavior in response to real-time feedback and incentives. It is anticipated that this approach will establish a feedback loop that 'learns' traveler preferences and customizes incentives to meet or exceed energy efficiency targets by empowering individual travelers with information needed to make energy-efficient choices and reducing the complexity required to validate transportation system energy savings. This handout provides an overview of NREL's Connected Traveler project, including graphics, milestones, and contact information.

Electricity decision-making: New techniques for calculating statewide economic impacts from new power supply and demand-side management programs

Science.gov (United States)

Tegen, Suzanne Isabel Helmholz

This dissertation introduces new techniques for calculating and comparing statewide economic impacts from new coal, natural gas and wind power plants, as well as from demand-side management programs. The impetus for this work was two-fold. First, reviews of current literature and projects revealed that there was no standard way to estimate statewide economic impacts from new supply- and demand-side electricity options. Second, decision-makers who were interviewed stated that they were overwhelmed with data in general, but also lacked enough specific information about economic development impacts to their states from electricity, to make informed choices. This dissertation includes chapters on electricity decision-making and on economic impacts from supply and demand. The supply chapter compares different electricity options in three states which vary in natural resource content: Arizona, Colorado and Michigan. To account for differing capacity factors, resources are compared on a per-megawatt-hour basis. The calculations of economic impacts from new supply include: materials and labor for construction, operations, maintenance, fuel extraction, fuel transport, as well as property tax, financing and landowner revenues. The demand-side chapter compares residential, commercial and industrial programs in Iowa. Impact calculations include: incremental labor and materials for program planning, installation and operations, as well as sales taxes and electricity saved. Results from supply-side calculations in the three states analyzed indicate that adding new wind power can have a greater impact to a state's economy than adding new gas or coal power due to resource location, taxes and infrastructure. Additionally, demand-side management programs have a higher relative percentage of in-state dollar flow than supply-side solutions, though demand-side programs typically involve fewer MWh and dollars than supply-side generation. Methods for this dissertation include researching

Towards a greener tomorrow: the future for solar electricity

International Nuclear Information System (INIS)

Hartford, John

1998-01-01

A typical photovoltaic (PV) system consisting of an array of photovoltaic cells which convert sunlight directly into DC electricity silently and without pollution is simple and reliable, easy to install and requires little maintenance and no refuelling. However, there are a number of technical, economic and structural problems to be overcome before photovoltaics achieve significant penetration in the energy market. The main technical barrier is the low energy density of sunlight and its uneven distribution. Furthermore, photovoltaics cannot produce electricity at night and although battery storage can be provided or PV systems can be connected to the grid, this adds to the cost. Cost is the major barrier to penetration of the market but this is continually being cut. Advances in solar cell design are discussed which are bringing down the cost of fabrication and this added to economics of scale as market share develops will eventually make PV systems more competitive. So far, PV systems have found their largest market in powering isolated devices and in the infrastructure of remote rural communities in developing countries but grid connected systems, both centralised power generation plants and building integrated systems, are expected to take over the largest share of the PV market by 2010. (UK)

Optimal Operation of Network-Connected Combined Heat and Powers for Customer Profit Maximization

Directory of Open Access Journals (Sweden)

Da Xie

2016-06-01

Full Text Available Network-connected combined heat and powers (CHPs, owned by a community, can export surplus heat and electricity to corresponding heat and electric networks after community loads are satisfied. This paper proposes a new optimization model for network-connected CHP operation. Both CHPs’ overall efficiency and heat to electricity ratio (HTER are assumed to vary with loading levels. Based on different energy flow scenarios where heat and electricity are exported to the network from the community or imported, four profit models are established accordingly. They reflect the different relationships between CHP energy supply and community load demand across time. A discrete optimization model is then developed to maximize the profit for the community. The models are derived from the intervals determined by the daily operation modes of CHP and real-time buying and selling prices of heat, electricity and natural gas. By demonstrating the proposed models on a 1 MW network-connected CHP, results show that the community profits are maximized in energy markets. Thus, the proposed optimization approach can help customers to devise optimal CHP operating strategies for maximizing benefits.

Wireless Open-Circuit In-Plane Strain and Displacement Sensor Requiring No Electrical Connections

Science.gov (United States)

Woodard, Stanley E. (Inventor)

2014-01-01

A wireless in-plane strain and displacement sensor includes an electrical conductor fixedly coupled to a substrate subject to strain conditions. The electrical conductor is shaped between its ends for storage of an electric field and a magnetic field, and remains electrically unconnected to define an unconnected open-circuit having inductance and capacitance. In the presence of a time-varying magnetic field, the electrical conductor so-shaped resonates to generate harmonic electric and magnetic field responses. The sensor also includes at least one electrically unconnected electrode having an end and a free portion extending from the end thereof. The end of each electrode is fixedly coupled to the substrate and the free portion thereof remains unencumbered and spaced apart from a portion of the electrical conductor so-shaped. More specifically, at least some of the free portion is disposed at a location lying within the magnetic field response generated by the electrical conductor. A motion guidance structure is slidingly engaged with each electrode's free portion in order to maintain each free portion parallel to the electrical conductor so-shaped.

Yeu and Noirmoutier islands - Electric connection to the offshore wind farm. Brochure 'Electric connection of the offshore wind farm to the Yeu and Noirmoutier islands' - Consultation file, December 2015, District of Vendee. Document of contribution to the public debate. Yeu and Noirmoutier islands offshore wind farm project - Project commissioner file

International Nuclear Information System (INIS)

Boyadjis, Jean-Marc; Corallo, Christian

2015-05-01

After a brief presentation of the context, a first document presents the connection characteristics, the general route of the electrical connection, how the sea and ground environment is taken into account, how the population is consulted for the project, the organisation of the public inquiry. The second document presents the consultation file with a description of the adopted solution and main characteristics of the project of connection of offshore wind farms about the Yeu and Noirmoutier islands, an analysis of the initial condition of the environment (physical and natural environment, landscapes and heritage, human and social-economic context), a description and a comparative analysis of proposed beams for the underwater connection, landfall and underground connection, and the planned continuation of the project (consultation, administrative procedure, planning). The next document aims at presenting the project before public consultation: objectives, underwater and underground connections with some of their technical characteristics, planning. Another document also presents the offshore wind farm project, its energetic and technical characteristics, how it is integrated into its environment (stakes and challenges, impacts on landscape and on activities), how it is an example of the development of offshore wind energy sector. It is completed by several appendices containing a variety of data on these issues. A last document is a presentation of the project by the project commissioner (RTE) which notably addresses how technical and environmental issues are to be addressed

Thermoacoustic magnetohydrodynamic electrical generator

International Nuclear Information System (INIS)

Wheatley, J.C.; Swift, G.W.; Migliori, A.

1986-01-01

A thermoacoustic magnetohydrodynamic electrical generator is described comprising a magnet having a magnetic field, an elongate hollow housing containing an electrically conductive liquid and a thermoacoustic structure positioned in the liquid, heat exchange means thermally connected to the thermoacoustic structure for inducing the liquid to oscillate at an acoustic resonant frequency within the housing. The housing is positioned in the magnetic field and oriented such that the direction of the magnetic field and the direction of oscillatory motion of the liquid are substantially orthogonal to one another, first and second electrical conductor means connected to the liquid on opposite sides of the housing along an axis which is substantially orthogonal to both the direction of the magnetic field and the direction of oscillatory motion of the liquid, an alternating current output signal is generated in the conductor means at a frequency corresponding to the frequency of the oscillatory motion of the liquid

The True Cost of Electric Power. An Inventory of Methodologies to Support Future Decision-making in Comparing the Cost and Competitiveness of Electricity Generation Technologies. Summary for policy-makers

International Nuclear Information System (INIS)

Burtraw, Dallas; Krupnick, Alan

2012-06-01

In energy markets across the world, market prices for fossil fuels are often lower than the prices of energy generated from renewable sources, such as solar, wind, and bio-fuels. These market prices, however, don't take into account the 'true costs' of the energy being sold, because they ignore the external costs to society caused by pollution and its resulting burdens, including damages to public health and the environment. Accounting for these externalities can as much as double the cost of some fossil fuels and, in some cases, make them more expensive than renewables. Because renewable forms of energy have far lower external costs than energy generated from fossil fuels, if one can implement policies that incorporate those costs into the price of electricity generated from all technologies, the playing field levels out and renewables can compete on a more fair and economically justified basis. The challenge, of course, is determining those 'true costs'. Estimating the true costs of electricity generation is both complex and controversial. It is complex because it must take into account several factors, including the population density near a power plant, the fuel it uses, and its pollution abatement technology. It is controversial because it requires assumptions and decisions to be made that the public does not like or does not understand. These include monetizing some types of risks (for example, to health) and ignoring others, such as occupational risks from coal mining when they are already 'internalized' by the coal company in the wages it pays. Finally, these approaches are certain to be controversial because they can affect billions of dollars in investments in electricity generation. This report, The True Cost of Electric Power, examines the various methods that have been used to measure such 'true' costs and looks at how such estimates can be used in company decision-making and public policy to ensure that

Intelligent Electricity Broker

DEFF Research Database (Denmark)

Grode, Jesper Nicolai Riis; Væggemose, Poul Erik; Kulik, Tomas

The Intelligent Electricity Broker (IEB) is a new energy storage and energy broker facility that serves two purposes. Firstly, it allows for storing excessive energy in the Smart Grid [1, 2, 3] it is connected to. Secondly, it runs a broker-algorithm that ensures that energy is purchased and sold...... when feasible to the system owner. This paper describes how the IEB can be used by house owners, in building clusters, and/or by energy providers to take advantage of electricity stock market prices and weather forecasts to control energy surplus storage suffers as well as to lower electricity bills...

An IoT architecture for cloud connected electric vehicles

NARCIS (Netherlands)

Ramamurthy, P.

2015-01-01

This report presents the EV-user scenario as an use-case of a hyper-connected environment. The need for efforts on standardisation in the IoT world is explained with a detailed view of the software architecture to achieve it.

Social interactions elicit rapid shifts in functional connectivity in the social decision-making network of zebrafish.

Science.gov (United States)

Teles, Magda C; Almeida, Olinda; Lopes, João S; Oliveira, Rui F

2015-10-07

According to the social decision-making (SDM) network hypothesis, SDM is encoded in a network of forebrain and midbrain structures in a distributed and dynamic fashion, such that the expression of a given social behaviour is better reflected by the overall profile of activation across the different loci rather than by the activity of a single node. This proposal has the implicit assumption that SDM relies on integration across brain regions, rather than on regional specialization. Here we tested the occurrence of functional localization and of functional connectivity in the SDM network. For this purpose we used zebrafish to map different social behaviour states into patterns of neuronal activity, as indicated by the expression of the immediate early genes c-fos and egr-1, across the SDM network. The results did not support functional localization, as some loci had similar patterns of activity associated with different social behaviour states, and showed socially driven changes in functional connectivity. Thus, this study provides functional support to the SDM network hypothesis and suggests that the neural context in which a given node of the network is operating (i.e. the state of its interconnected areas) is central to its functional relevance. © 2015 The Author(s).

Control of Power and Voltage of Solar Grid Connected

OpenAIRE

Allah, Boucetta Abd; Djamel, Labed

2016-01-01

Renewable energy is high on International agendas. Currently, grid-connected photovoltaic systems are a popular technology to convert solar energy into electricity. Control of power injected into the grid, maximum power point, high efficiency, and low total harmonic distortion of the currents injected into the grid are the requirements for inverter connection into the grid. Consequently, the performance of the inverters connected to the grid depends largely on the control strategy applied. In...

Quantized Abelian principle connections on Lorentzian manifolds

International Nuclear Information System (INIS)

Benini, Marco; Schenkel, Alexander

2013-03-01

We construct a covariant functor from a category of Abelian principal bundles over globally hyperbolic spacetimes to a category of *-algebras that describes quantized principal connections. We work within an appropriate differential geometric setting by using the bundle of connections and we study the full gauge group, namely the group of vertical principal bundle automorphisms. Properties of our functor are investigated in detail and, similar to earlier works, it is found that due to topological obstructions the locality property of locally covariant quantum field theory is violated. Furthermore, we prove that, for Abelian structure groups containing a nontrivial compact factor, the gauge invariant Borchers- Uhlmann algebra of the vector dual of the bundle of connections is not separating on gauge equivalence classes of principal connections. We introduce a topological generalization of the concept of locally covariant quantum fields. As examples, we construct for the full subcategory of principal U(1)-bundles two natural transformations from singular homology functors to the quantum field theory functor that can be interpreted as the Euler class and the electric charge. In this case we also prove that the electric charges can be consistently set to zero, which yields another quantum field theory functor that satisfies all axioms of locally covariant quantum field theory.

Quantized Abelian principle connections on Lorentzian manifolds

Energy Technology Data Exchange (ETDEWEB)

Benini, Marco [Pavia Univ. (Italy); Istituto Nazionale di Fisica Nucleare, Pavia (Italy); Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Dappiaggi, Claudio [Pavia Univ. (Italy); Istituto Nazionale di Fisica Nucleare, Pavia (Italy); Schenkel, Alexander [Bergische Univ., Wuppertal (Germany). Fachgruppe Mathematik

2013-03-15

We construct a covariant functor from a category of Abelian principal bundles over globally hyperbolic spacetimes to a category of *-algebras that describes quantized principal connections. We work within an appropriate differential geometric setting by using the bundle of connections and we study the full gauge group, namely the group of vertical principal bundle automorphisms. Properties of our functor are investigated in detail and, similar to earlier works, it is found that due to topological obstructions the locality property of locally covariant quantum field theory is violated. Furthermore, we prove that, for Abelian structure groups containing a nontrivial compact factor, the gauge invariant Borchers- Uhlmann algebra of the vector dual of the bundle of connections is not separating on gauge equivalence classes of principal connections. We introduce a topological generalization of the concept of locally covariant quantum fields. As examples, we construct for the full subcategory of principal U(1)-bundles two natural transformations from singular homology functors to the quantum field theory functor that can be interpreted as the Euler class and the electric charge. In this case we also prove that the electric charges can be consistently set to zero, which yields another quantum field theory functor that satisfies all axioms of locally covariant quantum field theory.

Electric power distribution handbook

CERN Document Server

Short, Thomas Allen

2014-01-01

Of the ""big three"" components of electrical infrastructure, distribution typically gets the least attention. In fact, a thorough, up-to-date treatment of the subject hasn't been published in years, yet deregulation and technical changes have increased the need for better information. Filling this void, the Electric Power Distribution Handbook delivers comprehensive, cutting-edge coverage of the electrical aspects of power distribution systems. The first few chapters of this pragmatic guidebook focus on equipment-oriented information and applications such as choosing transformer connections,

The Fermilab Main Injector dipole and quadrupole cooling design and bus connections

International Nuclear Information System (INIS)

Satti, J.A.

1995-06-01

The proposed system for connecting the low conductivity water (LCW) and the electrical power to the magnets is explained. This system requires minimum maintenance. Stainless steel headers supply LCW to local, secondary manifolds which regulate the flow to the dipole and to the copper bus which conduct both power and cooling water to the quadrupole. A combination of ceramic feedthroughs and thermoplastic hoses insulate the piping electrically from the copper bus system. The utilities for the Main Injector are grouped together at the outside wall of the tunnel leaving most of the enclosure space for servicing. Space above the headers is available for future accelerator expansion. The new dipoles have bolted electrical connections with flexible copper jumpers. Separate compression fittings are used for the water connections. Each dipole magnet has two water circuits in parallel designed to minimize thermal stresses and the number of insulators. Two electrical insulators are used in series because this design has been shown to minimize electrolyses problems and copper ion deposits inside the insulators. The design value of the temperature gradient of the LCW is 8 degrees C

Connecting Functions in Geometry and Algebra

Science.gov (United States)

Steketee, Scott; Scher, Daniel

2016-01-01

One goal of a mathematics education is that students make significant connections among different branches of mathematics. Connections--such as those between arithmetic and algebra, between two-dimensional and three-dimensional geometry, between compass-and-straight-edge constructions and transformations, and between calculus and analytic…

Enhanced electricity system analysis for decision making - A reference book[Inter-agency joint project on data bases and methodologies for comparative assessment of different energy sources for electricity generation

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-06-01

The objective of electricity system analysis in support of decision making is to provide comparative assessment results upon which relevant policy choices between alternative technology options and supply strategies can be based. This reference book offers analysts, planners and decision makers documented information on enhanced approaches to electricity system analysis, that can assist in achieving this objective. The book describes the main elements of comprehensive electricity system analysis and outlines an advanced integrated analysis and decision making framework for the electric power sector. Emphasis is placed on mechanisms for building consensus between interested and affected parties, and on aspects of planning that go beyond the traditional economic optimisation approach. The scope and contents of the book cover the topics to be addressed in decision making for the power sector and the process of integrating economic, social, health and environmental aspects in the comparative assessment of alternative options and strategies. The book describes and discusses overall frameworks, processes and state of the art methods and techniques available to analysts and planners for carrying out comparative assessment studies, in order to provide sound information to decision makers. This reference book is published as part of a series of technical reports and documents prepared in the framework of the inter-agency joint project (DECADES) on databases and methodologies for comparative assessment of different energy sources for electricity generation. The overall objective of the DECADES project is to enhance capabilities for incorporating economic, social, health and environmental issues in the comparative assessment of electricity generation options and strategies in the process of decision making for the power sector. The project, established in 1992, is carried out jointly by the European Commission (EC), the Economic and Social Commission for Asia and the Pacific

Conditions and costs for renewables electricity grid connection: Examples in Europe

International Nuclear Information System (INIS)

Swider, Derk J.; Beurskens, Luuk; Davidson, Sarah; Twidell, John; Pyrko, Jurek; Prueggler, Wolfgang; Auer, Hans; Vertin, Katarina; Skema, Romualdas

2008-01-01

This paper compares conditions and costs for RES-E grid connection in selected European countries. These are Germany, the Netherlands, the United Kingdom, Sweden, Austria, Lithuania and Slovenia. Country specific case studies are presented for wind onshore and offshore, biomass and photovoltaic power systems, as based on literature reviews and stakeholder interviews. It is shown that, especially for wind offshore, the allocation of grid connection costs can form a significant barrier for the installation of new RES-E generation if the developer has to bear all such costs. If energy policy makers want to reduce the barriers for new large-scale RES-E deployment, then it is concluded that the grid connection costs should be covered by the respective grid operator. These costs may then be recouped by increasing consumer tariffs for the use of the grid. (author)

Hybrid electric vehicle power management system

Science.gov (United States)

Bissontz, Jay E.

2015-08-25

Level voltage levels/states of charge are maintained among a plurality of high voltage DC electrical storage devices/traction battery packs that are arrayed in series to support operation of a hybrid electric vehicle drive train. Each high voltage DC electrical storage device supports a high voltage power bus, to which at least one controllable load is connected, and at least a first lower voltage level electrical distribution system. The rate of power transfer from the high voltage DC electrical storage devices to the at least first lower voltage electrical distribution system is controlled by DC-DC converters.

Synaptic Effects of Electric Fields

Science.gov (United States)

Rahman, Asif

Learning and sensory processing in the brain relies on the effective transmission of information across synapses. The strength and efficacy of synaptic transmission is modifiable through training and can be modulated with noninvasive electrical brain stimulation. Transcranial electrical stimulation (TES), specifically, induces weak intensity and spatially diffuse electric fields in the brain. Despite being weak, electric fields modulate spiking probability and the efficacy of synaptic transmission. These effects critically depend on the direction of the electric field relative to the orientation of the neuron and on the level of endogenous synaptic activity. TES has been used to modulate a wide range of neuropsychiatric indications, for various rehabilitation applications, and cognitive performance in diverse tasks. How can a weak and diffuse electric field, which simultaneously polarizes neurons across the brain, have precise changes in brain function? Designing therapies to maximize desired outcomes and minimize undesired effects presents a challenging problem. A series of experiments and computational models are used to define the anatomical and functional factors leading to specificity of TES. Anatomical specificity derives from guiding current to targeted brain structures and taking advantage of the direction-sensitivity of neurons with respect to the electric field. Functional specificity originates from preferential modulation of neuronal networks that are already active. Diffuse electric fields may recruit connected brain networks involved in a training task and promote plasticity along active synaptic pathways. In vitro, electric fields boost endogenous synaptic plasticity and raise the ceiling for synaptic learning with repeated stimulation sessions. Synapses undergoing strong plasticity are preferentially modulated over weak synapses. Therefore, active circuits that are involved in a task could be more susceptible to stimulation than inactive circuits

Using GIS to evaluate the impact of exclusion zones on the connection cost of wave energy to the electricity grid

International Nuclear Information System (INIS)

Prest, Robert; Daniell, Trevor; Ostendorf, Bertram

2007-01-01

An increase in the planning and environmental restrictions associated with wind energy has led to a growth in interest towards wave energy. However, as the connection cost of a wave energy development is a driving factor in the development's feasibility, existing wind farm cable-routing techniques used by renewable energy developers may not be satisfactory. A Geographical Information System (GIS) method is presented which optimises the cable route between a wave farm and the electricity network, while taking a range of exclusion zones, such as native vegetation, into account. The optimisation is presented for a South Australian study area, which subsequently showed that exclusion zones reduce the number of suitable locations for wave energy by almost 40%. The method presented also assesses the effect that each exclusion zone applied has upon the number of suitable locations within the study area. The analysis undertaken showed that National Parks and cliffs pose a significant limitation to the potential of a wave energy industry within South Australia. Allowing the transmission route to travel through a National Park, or traverse a cliff, resulted in an increase in the number of locations from which a connection could be made to the electricity grid for less than $10 million of 33% and 50%, respectively. Conservation Parks, Wilderness Areas and native vegetation also have an effect upon the number of suitable locations for wave energy within South Australia. The GIS methods developed may be of assistance to governments in setting appropriate marine renewable energy policy, and also in identifying existing policy which may require amending if the government wishes to pursue and support the development of wave energy

Power system services provided by inverter connected distributed energy resources

DEFF Research Database (Denmark)

For the last few years there has been a significant increase of DER units in Denmark, of those units more and more are connected to the power system using inverters. These inverter connected units have the potential to support the electrical power system with various power system services. One...

Photovoltaic system with improved DC connections and method of making same

Energy Technology Data Exchange (ETDEWEB)

Cioffi, Philip Michael; Todorovic, Maja Harfman; Herzog, Michael Scott; Korman, Charles Steven; Doherty, Donald M.; Johnson, Neil Anthony

2017-06-20

A micro-inverter assembly includes a housing having an opening formed in a bottom surface thereof, and a direct current (DC)-to-alternating current (AC) micro-inverter disposed within the housing at a position adjacent to the opening. The micro-inverter assembly further includes a micro-inverter DC connector electrically coupled to the DC-to-AC micro-inverter and positioned within the opening of the housing, the micro-inverter DC connector having a plurality of exposed electrical contacts.

New consumer load prototype for electricity theft monitoring

International Nuclear Information System (INIS)

Abdullateef, A I; Salami, M J E; Musse, M A; Onasanya, M A; Alebiosu, M I

2013-01-01

Illegal connection which is direct connection to the distribution feeder and tampering of energy meter has been identified as a major process through which nefarious consumers steal electricity on low voltage distribution system. This has contributed enormously to the revenue losses incurred by the power and energy providers. A Consumer Load Prototype (CLP) is constructed and proposed in this study in order to understand the best possible pattern through which the stealing process is effected in real life power consumption. The construction of consumer load prototype will facilitate real time simulation and data collection for the monitoring and detection of electricity theft on low voltage distribution system. The prototype involves electrical design and construction of consumer loads with application of various standard regulations from Institution of Engineering and Technology (IET), formerly known as Institution of Electrical Engineers (IEE). LABVIEW platform was used for data acquisition and the data shows a good representation of the connected loads. The prototype will assist researchers and power utilities, currently facing challenges in getting real time data for the study and monitoring of electricity theft. The simulation of electricity theft in real time is one of the contributions of this prototype. Similarly, the power and energy community including students will appreciate the practical approach which the prototype provides for real time information rather than software simulation which has hitherto been used in the study of electricity theft

New consumer load prototype for electricity theft monitoring

Science.gov (United States)

Abdullateef, A. I.; Salami, M. J. E.; Musse, M. A.; Onasanya, M. A.; Alebiosu, M. I.

2013-12-01

Illegal connection which is direct connection to the distribution feeder and tampering of energy meter has been identified as a major process through which nefarious consumers steal electricity on low voltage distribution system. This has contributed enormously to the revenue losses incurred by the power and energy providers. A Consumer Load Prototype (CLP) is constructed and proposed in this study in order to understand the best possible pattern through which the stealing process is effected in real life power consumption. The construction of consumer load prototype will facilitate real time simulation and data collection for the monitoring and detection of electricity theft on low voltage distribution system. The prototype involves electrical design and construction of consumer loads with application of various standard regulations from Institution of Engineering and Technology (IET), formerly known as Institution of Electrical Engineers (IEE). LABVIEW platform was used for data acquisition and the data shows a good representation of the connected loads. The prototype will assist researchers and power utilities, currently facing challenges in getting real time data for the study and monitoring of electricity theft. The simulation of electricity theft in real time is one of the contributions of this prototype. Similarly, the power and energy community including students will appreciate the practical approach which the prototype provides for real time information rather than software simulation which has hitherto been used in the study of electricity theft.

Energy Management and Control of Plug-In Hybrid Electric Vehicle Charging Stations in a Grid-Connected Hybrid Power System

Directory of Open Access Journals (Sweden)

Sidra Mumtaz

2017-11-01

Full Text Available The charging infrastructure plays a key role in the healthy and rapid development of the electric vehicle industry. This paper presents an energy management and control system of an electric vehicle charging station. The charging station (CS is integrated to a grid-connected hybrid power system having a wind turbine maximum power point tracking (MPPT controlled subsystem, photovoltaic (PV MPPT controlled subsystem and a controlled solid oxide fuel cell with electrolyzer subsystem which are characterized as renewable energy sources. In this article, an energy management system is designed for charging and discharging of five different plug-in hybrid electric vehicles (PHEVs simultaneously to fulfil the grid-to-vehicle (G2V, vehicle-to-grid (V2G, grid-to-battery storage system (G2BSS, battery storage system-to-grid (BSS2G, battery storage system-to-vehicle (BSS2V, vehicle-to-battery storage system (V2BSS and vehicle-to-vehicle (V2V charging and discharging requirements of the charging station. A simulation test-bed in Matlab/Simulink is developed to evaluate and control adaptively the AC-DC-AC converter of non-renewable energy source, DC-DC converters of the storage system, DC-AC grid side inverter and the converters of the CS using adaptive proportional-integral-derivate (AdapPID control paradigm. The effectiveness of the AdapPID control strategy is validated through simulation results by comparing with conventional PID control scheme.

Estimating the maximum potential revenue for grid connected electricity storage :

Energy Technology Data Exchange (ETDEWEB)

Byrne, Raymond Harry; Silva Monroy, Cesar Augusto.

2012-12-01

The valuation of an electricity storage device is based on the expected future cash flow generated by the device. Two potential sources of income for an electricity storage system are energy arbitrage and participation in the frequency regulation market. Energy arbitrage refers to purchasing (stor- ing) energy when electricity prices are low, and selling (discharging) energy when electricity prices are high. Frequency regulation is an ancillary service geared towards maintaining system frequency, and is typically procured by the independent system operator in some type of market. This paper outlines the calculations required to estimate the maximum potential revenue from participating in these two activities. First, a mathematical model is presented for the state of charge as a function of the storage device parameters and the quantities of electricity purchased/sold as well as the quantities o ered into the regulation market. Using this mathematical model, we present a linear programming optimization approach to calculating the maximum potential revenue from an elec- tricity storage device. The calculation of the maximum potential revenue is critical in developing an upper bound on the value of storage, as a benchmark for evaluating potential trading strate- gies, and a tool for capital nance risk assessment. Then, we use historical California Independent System Operator (CAISO) data from 2010-2011 to evaluate the maximum potential revenue from the Tehachapi wind energy storage project, an American Recovery and Reinvestment Act of 2009 (ARRA) energy storage demonstration project. We investigate the maximum potential revenue from two di erent scenarios: arbitrage only and arbitrage combined with the regulation market. Our analysis shows that participation in the regulation market produces four times the revenue compared to arbitrage in the CAISO market using 2010 and 2011 data. Then we evaluate several trading strategies to illustrate how they compare to the

Improved Performance of Connected Foundations for Resilient Energy Transmission Infrastructure in Soft Soils

Directory of Open Access Journals (Sweden)

Doohyun Kyung

2015-12-01

Full Text Available The connected foundation is an effective structural type of foundation that can improve the sustainability of electrical transmission towers in soft soils to serve as a resilient energy supply system. In this study, the performance of electrical transmission towers reinforced with connected beams was investigated using a series of field load tests. Model transmission tower structures were manufactured and adopted into the tests. Based on the load capacity mobilization and failure mechanism, a criterion to define the load carrying capacity for connected foundation was proposed. It was found that the performance of connected foundation varies with the mechanical property of connection beam. The load capacity and differential settlement increased and decreased, respectively, with increasing connection beam stiffness. Such effect of connection beam was more pronounced as the height of load application point or tower height (zh increases. Based on the load test results, a design model was proposed that can be used to evaluate the sustainable performance and load carrying capacity of connected foundations. Field load tests with prototype transmission tower structure models were conducted to check and confirm the performance of connected foundation and the proposed design method.

Development of an exergy-electrical analogy for visualizing and modeling building integrated energy systems

International Nuclear Information System (INIS)

Saloux, E.; Teyssedou, A.; Sorin, M.

2015-01-01

Highlights: • The exergy-electrical analogy is developed for energy systems used in buildings. • This analogy has been developed for a complete set of system arrangement options. • Different possibilities of inter-connections are illustrated using analog switches. • Adaptability and utility of the diagram over traditional ones are emphasized. - Abstract: An exergy-electrical analogy, similar to the heat transfer electrical one, is developed and applied to the case of integrated energy systems operating in buildings. Its construction is presented for the case of space heating with electric heaters, heat pumps and solar collectors. The proposed analogy has been applied to a set of system arrangement options proposed for satisfying the building heating demand (space heating, domestic hot water); different alternatives to connect the units have been presented with switches in a visualization scheme. The analogy for such situation has been performed and the study of a solar assisted heat pump using ice storage has been investigated. This diagram directly permits energy paths and their associated exergy destruction to be visualized; hence, sources of irreversibility are identifiable. It can be helpful for the comprehension of the global process and its operation as well as for identifying exergy losses. The method used to construct the diagram makes it easily adaptable to others units or structures or to others models depending on the complexity of the process. The use of switches could be very useful for optimization purposes

Music Technology and Musical Creativity: Making Connections

Science.gov (United States)

Thompson, Douglas Earl

2012-01-01

This article is a preview of Scott Watson's new book, "Using Technology to Unlock Musical Creativity" (Oxford University Press, 2011). The book's main contents are summarized and one of the volume's 29 lessons is provided to assist readers in evaluating the book for their use. Particular attention is given to Watson's success in making the…

Making students' frames explicit

DEFF Research Database (Denmark)

Nielsen, Louise Møller; Hansen, Poul Henrik Kyvsgaard

2016-01-01

Framing is a vital part of the design and innovation process. Frames are cognitive shortcuts (i.e. metaphors) that enable designers to connect insights about i.e. market opportunities and users needs with a set of solution principles and to test if this connection makes sense. Until now, framing...

Electric Vehicle Grid Integration | Transportation Research | NREL

Science.gov (United States)

Electric Vehicle Grid Integration Electric Vehicle Grid Integration Illustration of a house with a in the garage, is connected via a power cord to a household outlet. A sustainable transportation sustainable transportation technologies to increase the capacity, efficiency, and stability of the grid

Making a Simple Self-Starting Electric Motor

Science.gov (United States)

Hong, Seok-In; Choi, Jung-In; Hong, Seok-Cheol

2009-01-01

A simple electric motor has a problem in that the current applied to the motor per se can rarely trigger its rotation. Usually such motors begin to rotate after the rotor is slightly turned by hand (i.e., manual starting). In a "self-starting" motor, the rotor starts to rotate spontaneously as soon as the current is applied. This paper describes…

The supply expansion of electricity in Brazilian urban centers through connected photovoltaic systems' network; A expansao da oferta de energia eletrica nos centros urbanos brasileiros por meio de sistemas fotovoltaicos conectados a rede

Energy Technology Data Exchange (ETDEWEB)

Benedito, Ricardo da Silva; Zilles, Roberto [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Eletrotecnica e Energia. Lab. de Sistemas Fotovoltaicos

2010-07-01

This paper aims to outline perspectives on the electricity production through Grid-Connected Photovoltaic Systems (GCPS), in Brazil, and its insertion on a large scale in the energy matrix, as a supplementary power generation source. The GCPS bring several benefits to the Electrical Sector and the environment by producing energy cleanly and quietly in the places of consumption, avoiding the construction of large power plants and avoiding additional costs with transmission and distribution. In general, these systems can be integrated into the buildings architecture, taking advantage of the rooftop of pre-existing buildings. But, although it has high solar potential, Brazil had been installed a capacity of only 161.32 kWp GCPS until December 2009, a value considered negligible compared, for instance, with 4.5 GWp installed in Europe alone in 2008. This study shows that the cost of generation from a GCPS is still high, reaching to 2.4 times higher than the average residential tariff practiced in Brazil, which turns the technology impracticable commercially. But it shows a trend of equalization between these two values in the next decade for various locations, which will certainly make the GCPS to be considered as an alternative for expanding the energy supply. But for the lack of appropriate technical criteria do not affect the spread of this technology in the future, it is necessary a correct regulation of this activity by the staff of the Electrical Sector. (author)

Control voltage and power fluctuations when connecting wind farms

Science.gov (United States)

Berinde, Ioan; Bǎlan, Horia; Oros Pop, Teodora Susana

2015-12-01

Voltage, frequency, active power and reactive power are very important parameters in terms of power quality. These parameters are followed when connecting any power plant, the more the connection of wind farms. Connecting wind farms to the electricity system must not cause interference outside the limits set by regulations. Modern solutions for fast and automatic voltage control and power fluctuations using electronic control systems of reactive power flows. FACTS (Flexible Alternating Current Transmision System) systems, established on the basis of power electronic circuits ensure control of electrical status quantities to achieve the necessary transfer of power to the power grid. FACTS devices can quickly control parameters and sizes of state power lines, such as impedance line voltages and phase angles of the voltages of the two ends of the line. Their use can lead to improvement in power system operation by increasing the transmission capacity of power lines, power flow control lines, improved static and transient stability reserve.

Control voltage and power fluctuations when connecting wind farms

International Nuclear Information System (INIS)

Berinde, Ioan; Bălan, Horia; Oros, Teodora Susana

2015-01-01

Voltage, frequency, active power and reactive power are very important parameters in terms of power quality. These parameters are followed when connecting any power plant, the more the connection of wind farms. Connecting wind farms to the electricity system must not cause interference outside the limits set by regulations. Modern solutions for fast and automatic voltage control and power fluctuations using electronic control systems of reactive power flows. FACTS (Flexible Alternating Current Transmision System) systems, established on the basis of power electronic circuits ensure control of electrical status quantities to achieve the necessary transfer of power to the power grid. FACTS devices can quickly control parameters and sizes of state power lines, such as impedance line voltages and phase angles of the voltages of the two ends of the line. Their use can lead to improvement in power system operation by increasing the transmission capacity of power lines, power flow control lines, improved static and transient stability reserve

Control voltage and power fluctuations when connecting wind farms

Energy Technology Data Exchange (ETDEWEB)

Berinde, Ioan, E-mail: ioan-berinde@yahoo.com; Bălan, Horia, E-mail: hbalan@mail.utcluj.ro; Oros, Teodora Susana, E-mail: teodoraoros-87@yahoo.com [Technical University of Cluj-Napoca, Romania, Faculty of Electrical Engineering, Department of Power Engineering and Management (Romania)

2015-12-23

Voltage, frequency, active power and reactive power are very important parameters in terms of power quality. These parameters are followed when connecting any power plant, the more the connection of wind farms. Connecting wind farms to the electricity system must not cause interference outside the limits set by regulations. Modern solutions for fast and automatic voltage control and power fluctuations using electronic control systems of reactive power flows. FACTS (Flexible Alternating Current Transmision System) systems, established on the basis of power electronic circuits ensure control of electrical status quantities to achieve the necessary transfer of power to the power grid. FACTS devices can quickly control parameters and sizes of state power lines, such as impedance line voltages and phase angles of the voltages of the two ends of the line. Their use can lead to improvement in power system operation by increasing the transmission capacity of power lines, power flow control lines, improved static and transient stability reserve.

System for detecting and limiting electrical ground faults within electrical devices

International Nuclear Information System (INIS)

Gaubatz, D.C.

1990-01-01

This paper discusses, in a nuclear power plant of a variety wherein a reactor is provided including a reactor vessel retaining a liquid metal coolant, a reactor core and an electromagnetic pump having inductive windings insulatively retained within the electrically conductive wall of an enclosure, the method for controlling electrical ground fault current between a the inductive winding and the walls. It comprises providing an electrically isolated power source by inductive coupling with the plant power supply; rectifying the power source to provide an isolated d.c. power source; providing an inverter powered from the isolated d.c. power source under the control of the plant control system for selectively energizing the inductive windings; providing a fault control conductor electrically connected with the pump enclosure wall and extending as an electrical return for ground fault current to the inverter; and providing an electrical resistance between the conductor and the isolated inverter having an impedance selected to limit the fault current below a predetermined value limiting arc damage at any the electrical ground fault location

Effect of AC electric fields on flame spread over electrical wire

KAUST Repository

Kim, Minkuk

2011-01-01

The effect of electric fields on the characteristics of flame spread over insulated electrical wire has been investigated experimentally by varying AC voltage and frequency applied to the wire in the normal gravity condition. The polyethylene (PE) insulated electrical wire was placed horizontally on electrically non-conducting posts and one end of the wire was connected to the high voltage terminal. Thus, the electrical system is the single electrode configuration. The wire was ignited at one end and the flame spread rate along the wire has been measured from the images using a video camera. Two distinct regimes existed depending on the applied AC frequency. In the low frequency regime, the flame spread rate decreased with the frequency and voltage. While in the high frequency regime, it decreased initially with voltage and then increased. At high frequency, the spread rate was even over that without applying electric fields. This result implies that fire safety codes developed without considering the effect of electric fields may require modifications. © 2010 Published by Elsevier Inc. on behalf of The Combustion Institute. All rights reserved.

Connected vehicles and cybersecurity.

Science.gov (United States)

2016-01-01

Connected vehicles are a next-generation technology in vehicles and in infrastructure that will make travel safer, cleaner, and more efficient. The advanced wireless technology enables vehicles to share and communicate information with each other and...

Non-conventional rule of making a periodically varying different-pole magnetic field in low-power alternating current electrical machines with using ring coils in multiphase armature winding

Science.gov (United States)

Plastun, A. T.; Tikhonova, O. V.; Malygin, I. V.

2018-02-01

The paper presents methods of making a periodically varying different-pole magnetic field in low-power electrical machines. Authors consider classical designs of electrical machines and machines with ring windings in armature, structural features and calculated parameters of magnetic circuit for these machines.

DIAMOND: A model of incremental decision making for resource acquisition by electric utilities

Energy Technology Data Exchange (ETDEWEB)

Gettings, M.; Hirst, E.; Yourstone, E.

1991-02-01

Uncertainty is a major issue facing electric utilities in planning and decision making. Substantial uncertainties exist concerning future load growth; the lifetimes and performances of existing power plants; the construction times, costs, and performances of new resources being brought online; and the regulatory and economic environment in which utilities operate. This report describes a utility planning model that focuses on frequent and incremental decisions. The key features of this model are its explicit treatment of uncertainty, frequent user interaction with the model, and the ability to change prior decisions. The primary strength of this model is its representation of the planning and decision-making environment that utility planners and executives face. Users interact with the model after every year or two of simulation, which provides an opportunity to modify past decisions as well as to make new decisions. For example, construction of a power plant can be started one year, and if circumstances change, the plant can be accelerated, mothballed, canceled, or continued as originally planned. Similarly, the marketing and financial incentives for demand-side management programs can be changed from year to year, reflecting the short lead time and small unit size of these resources. This frequent user interaction with the model, an operational game, should build greater understanding and insights among utility planners about the risks associated with different types of resources. The model is called DIAMOND, Decision Impact Assessment Model. In consists of four submodels: FUTURES, FORECAST, SIMULATION, and DECISION. It runs on any IBM-compatible PC and requires no special software or hardware. 19 refs., 13 figs., 15 tabs.

Electric distribution systems and embedded generation capacity

International Nuclear Information System (INIS)

Calderaro, V.; Galdi, V.; Piccolo, A.; Siano, P.

2006-01-01

The main policy issues of European States are sustainable energy supply promotion and liberalization of energy markets, which introduced market competition in electricity production and created support mechanisms to encourage renewable electricity production and consumption. As a result of liberalization, any generator, including small-scale and renewable energy based units, can sell electricity on the free market. In order to meet future sustainability targets, connection of a higher number of Distributed Generation (DG) units to the electrical power system is expected, requiring changes in the design and operation of distribution electricity systems, as well as changes in electricity network regulation. In order to assist distribution system operators in planning and managing DG connections and in maximizing DG penetration and renewable sources exploitation, this paper proposed a reconfiguration methodology based on a Genetic Algorithm (GA), that was tested on a 70-bus system with DG units. The simulation results confirmed that the methodology represents a suitable tool for distribution system operators when dealing with DG capacity expansion and power loss issues, providing information regarding the potential penetration network-wide and allowing maximum exploitation of renewable generation. 35 refs., 4 tabs., 6 figs

Anonymous Connections and Onion Routing

National Research Council Canada - National Science Library

Syverson, Paul F; Goldschlag, David M; Reed, Michael G

1997-01-01

.... Unmodified Internet applications can use these anonymous connections by means of proxies. The proxies may also make communication anonymous by removing identifying information from the data stream...

Research, development and innovation in the electrical energy sector of Brazil: toward a tool for the support of the decision-making process

Energy Technology Data Exchange (ETDEWEB)

Machado, Fernando Vieira; Salles-Filho, Sergio; Brittes, Jose Juiz Pereira; Corder, Solange Maria; Boer, Denile Cominato [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

2008-07-01

The objective of this article is to present a tool to help in the decision making process for the allocation of resources for research, development and innovation in the electrical energy sector in Brazil. It provides a computerized tool for the management of a portfolio of projects which contains myriads of information of projects of research, development, and innovation financed by companies in the area of the generation, transmission and distribution of electrical energy in Brazil. This tool permits the collection and analysis of this information with a view to evaluating the direction and progress of investments made in the past five years. The electrical energy sector of Brazil invests hundreds of millions of reals each year in research and development (henceforth 'R and D'). The investment of these resources is required by a set of federal laws. This legal framework is a consequence of the process of the privatization of the sector which began in 1997. The investment of the financial resources in R and D projects is supervised by the Brazilian Electricity Regulatory Agency (henceforth 'ANEEL'). It is the responsibility of ANEEL to evaluate and approve proposed R and D projects, and monitor their results, as per the 'Handbook of R and D of the Electrical Energy Sector.' This tool for supporting the decision-making process serves exactly the purpose of helping both ANEEL in the approval of resources under its supervision, as well as helping companies within the electrical energy sector in the management of applied resources. Almost one billion reals (approximately US $500,000,000) were invested in more than 3000 projects from 1998 to 2006. The data base associated with these projects already contains information concerning 1412 projects from 1998 to 2004, permitting significant analyses of the results and impacts of the allocation of resources. (author)

Households under the impression of the energy turnaround. Development of electricity demand and load profiles; Die Haushalte im Zeichen der Energiewende. Entwicklung der Stromnachfrage und Lastprofile

Energy Technology Data Exchange (ETDEWEB)

Elsland, Rainer; Bossmann, Tobias; Gnann, Till; Wietschel, Martin [Fraunhofer-Institut fuer System- und Innovationsforschung (ISI), Karlsruhe (Germany); Hartel, Rupert; Fichtner, Wolf [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Inst. fuer Industriebetriebslehre und Industrielle Produktion (IIP)

2013-01-15

One of the central components of the energy turnaround is the improvement of energy efficiency. Households play a key role in this connection, not only due to their high potentials for saving energy and shifting loads, but also because of the growing importance of electricity as an energy carrier. This makes it interesting to explore how the continuing dissemination of efficient energy applications, electromobility and decentralised electricity production through photovoltaics will impact on load and electricity production profiles in the German household sector until the year 2040. The results show that with ambitious energy policy goals it will be possible to lower the electricity demand of households by 30%. However, this decrease could be more than undone by electromobility.

Grid-connected photovoltaic system design for local government ...

African Journals Online (AJOL)

Grid-connected photovoltaic system design for local government offices in Nigeria. ... Nigerian Journal of Technology. Journal Home ... It is neat, silent and elegant process of generating electric power in environmentally friendly manner. In this ...

Hybrid and Electric Advanced Vehicle Systems Simulation

Science.gov (United States)

Beach, R. F.; Hammond, R. A.; Mcgehee, R. K.

1985-01-01

Predefined components connected to represent wide variety of propulsion systems. Hybrid and Electric Advanced Vehicle System (HEAVY) computer program is flexible tool for evaluating performance and cost of electric and hybrid vehicle propulsion systems. Allows designer to quickly, conveniently, and economically predict performance of proposed drive train.

Modeling and Grid impedance Variation Analysis of Parallel Connected Grid Connected Inverter based on Impedance Based Harmonic Analysis

DEFF Research Database (Denmark)

Kwon, JunBum; Wang, Xiongfei; Bak, Claus Leth

2014-01-01

This paper addresses the harmonic compensation error problem existing with parallel connected inverter in the same grid interface conditions by means of impedance-based analysis and modeling. Unlike the single grid connected inverter, it is found that multiple parallel connected inverters and grid...... impedance can make influence to each other if they each have a harmonic compensation function. The analysis method proposed in this paper is based on the relationship between the overall output impedance and input impedance of parallel connected inverter, where controller gain design method, which can...

Drafting method of electricity and electron design

International Nuclear Information System (INIS)

Gungbon, Junchun

1989-11-01

This book concentrates on drafting of electricity and electron design. It deals with The meaning of electricity and electron drafting JIS standard regulation the types of drafting and line and letter, basics drafting with projection drafting method, plan projection and development elevation, Drafting method of shop drawing, practical method of design and drafting, Design and drafting of technic and illustration, Connection diagram, Drafting of wiring diagram for light and illumination, Drafting of development connection diagram for sequence control, Drafting of logic circuit sign of flow chart and manual, drafting for a electron circuit diagram and Drawing of PC board.

Modernization Of Electrical Installation By Using Wireless Remote Control

Directory of Open Access Journals (Sweden)

Mawlood M Al – Hamad

2013-05-01

Full Text Available Great benefits can be achieved by using wireless remote control in electrical wiring systems of buildings.     Probably the main advantage of this application is the drastic saving in wiring installations, which in turn will give higher reliability, safety and economy.     The idea of this application can be summarized in the following explanation. '' Instead off connecting each point of electrical system to individual switch by wires, a remote receiver can be situated in a place near to the point. The transmitter is used to operate the point remotely. The mains are connected to the receiver which will connect or disconnect the load as required. Many points can be connected to one receiver and can be operated by one or more transmitter.

Connecting the Production Multiple

DEFF Research Database (Denmark)

Lichen, Alex Yu; Mouritsen, Jan

&OP process itself is a fluid object, but there is still possibility to organise the messy Production. There are connections between the Production multiple and the managerial technology fluid. The fluid enacted the multiplicity of Production thus making it more difficult to be organised because there were...... in opposite directions. They are all part of the fluid object. There is no single chain of circulating references that makes the object a matter of fact. Accounting fluidity means that references drift back and forth and enact new realities also connected to the chain. In this setting future research may......This paper is about objects. It follows post ANT trajectories and finds that objects are multiple and fluid. Extant classic ANT inspired accounting research largely sees accounting inscriptions as immutable mobiles. Although multiplicity of objects upon which accounting acts has been explored...

Experimental grid connected PV system power analysis

Science.gov (United States)

Semaoui, Smail; Abdeladim, Kamel; Arab, Amar Hadj; Boulahchich, Saliha; Amrouche, Said Ould; Yassaa, Noureddine

2018-05-01

Almost 80 % of Algerian territory is appropriate for the exploitation of solar energy. The Algerian energetic strategy provides a substantial injection of PV electricity to the national grid. Currently, about 344 MWp of PV arrays which corresponds approximately to 2,34 km2 of module surfaces, are connected on electricity grid over the national territory. The Algerian Northern regions are characterized by strong pollution and high humidity. These phenomena affect the energetic productivity of PV generator. The objective of our study is to analyze experimental grid connected PV system power in coastal locations. Hence, experiments have been conducted on three identical PV systems to determine the electrical performances. Transformer-less inverters are the most attractive for the ground-based photovoltaic (PV) system due to their efficiencies, reduced cost and weight. Besides, the absence of the galvanic isolation generates problems of capacitive leakage current on the AC side and the degradation of the insulation resistance on the DC side of the inverter. In this work, experimental study of the behavior of single-phase inverters without transformers is presented. The main objective of this work is to study the degradation of the insulation resistance at the input of the inverter, and the capacitive leakage current at the output of the inverter. This study was achieved at the CDER on a rainy day of 15/03/2017, on the first PV plant connected to the low voltage network in Algeria. This investigation can help forecasting the PV array energetic production by taking into account natural conditions.

Machine for welding solar cell connections

Energy Technology Data Exchange (ETDEWEB)

Lorans, D.Y.

1977-08-09

A machine for welding a connection wire over a solar cell electrode is described which comprises a base, a welding mount for the solar cell which is supported on the base, means for holding the solar cell on the welding mount, welding electrodes, means to lower the welding electrodes over the solar cell and the connection wire superimposed thereon, means for applying electric current pulses to said welding electrodes. It is characterized by the fact that it further comprises means for imparting to said mount an alternating transverse movement in relation to said base before and during the welding operation.

Low-voltage grid-connection of photovoltaic power systems

Energy Technology Data Exchange (ETDEWEB)

Collinson, A.; Thornycroft, J.

1999-07-01

This report summarises the results of a project aimed at developing technical guidelines concerning grid connected photovoltaic (PV) inverter generators which are to be published in draft form as the {sup U}K Technical Guidelines for Inverter Connected Single Phase Photovoltaic (PV) Generators up to 5kVA{sup .} The background to the use of PV in the UK is traced, and the technical criteria for electrical integration of PV systems, and UK guidelines for grid connected PV systems are examined. The findings of the working group of the International Energy Agency (IEA) Implementing Agreement on Photovoltaic Power Systems are also presented in this report. Appendices discuss the UK technical guidelines, the IEA Task V activities,, utility aspects of grid-connected PV systems, and demonstration tests on grid-connected PV systems, and lists Task V reports.

Risk perception & strategic decision making :general insights, a framework, and specific application to electricity generation using nuclear energy.

Energy Technology Data Exchange (ETDEWEB)

Brewer, Jeffrey D.

2005-11-01

The objective of this report is to promote increased understanding of decision making processes and hopefully to enable improved decision making regarding high-consequence, highly sophisticated technological systems. This report brings together insights regarding risk perception and decision making across domains ranging from nuclear power technology safety, cognitive psychology, economics, science education, public policy, and neural science (to name a few). It forms them into a unique, coherent, concise framework, and list of strategies to aid in decision making. It is suggested that all decision makers, whether ordinary citizens, academics, or political leaders, ought to cultivate their abilities to separate the wheat from the chaff in these types of decision making instances. The wheat includes proper data sources and helpful human decision making heuristics; these should be sought. The chaff includes ''unhelpful biases'' that hinder proper interpretation of available data and lead people unwittingly toward inappropriate decision making ''strategies''; obviously, these should be avoided. It is further proposed that successfully accomplishing the wheat vs. chaff separation is very difficult, yet tenable. This report hopes to expose and facilitate navigation away from decision-making traps which often ensnare the unwary. Furthermore, it is emphasized that one's personal decision making biases can be examined, and tools can be provided allowing better means to generate, evaluate, and select among decision options. Many examples in this report are tailored to the energy domain (esp. nuclear power for electricity generation). The decision making framework and approach presented here are applicable to any high-consequence, highly sophisticated technological system.

Initial plasma production by induction electric field on QUEST tokamak

International Nuclear Information System (INIS)

Hasegawa, Makoto; Nakamura, Kazuo; Sato, Kohnosuke

2007-01-01

Induction electric field by center solenoid coil plays a roll to produce initial plasma. According to Townsend avalanche theory, minimum electric field for plasma breakdown depends on neutral gas pressure and connection length. On QUEST spherical tokamak, a connection length is evaluated as 966m on null point neighborhood with coil current ratio I PF26 /I CS =0.1, and induction electric field considering eddy current of vacuum vessel is evaluated as about 0.1 V/m on null point neighborhood. With Townsend avalanche theory, these values manage to produce initial plasma on QUEST. (author)

Electrical signal transfer system for a rotary kiln

International Nuclear Information System (INIS)

Tyson, J.H.; Kennett, L.P.; Davidson, I.S.

1985-01-01

A rotary kiln has a number of thermocouples respectively sensing the kiln temperature at spaced locations and respectively connected to annular slip rings. Laterally facing peripheral surfaces of the rings are respectively cooperable with brush contacts connected to a bar and a fork which embraces a ring moveable axially with the rings. Thus on longitudinal expansion of the kiln the contacts are caused to move with the rings. The electric signals from the thermocouples are thus fed to stationary monitoring equipment. In a modification the ring sections are electrically isolated and each section is connected to a respective sensor. Position sensors may be used to detect the rotary position of the kiln. The invention can be applied to other sensors. (author)

Wireless Temperature Sensor Having No Electrical Connections and Sensing Method for Use Therewith

Science.gov (United States)

Woodard, Marie (Inventor)

2014-01-01

A wireless temperature sensor includes an electrical conductor and a dielectric material on the conductor. The conductor is electrically unconnected and is shaped for storage of an electric field and a magnetic field. In the presence of a time-varying magnetic field, the conductor resonates to generate harmonic electric and magnetic field responses, each of which has a frequency associated therewith. The material is selected such that it experiences changes in either dielectric or magnetic permeability attributes in the presence of a temperature change. Shifts from the sensor's baseline frequency response indicate that the material has experienced a temperature change.

Micro-generation network connection (renewables)

Energy Technology Data Exchange (ETDEWEB)

Thornycroft, J.; Russell, T.; Curran, J.

2003-07-01

The drive to reduce emissions of carbon dioxide will result in an increase in the number of small generation units seeking connection to the electric power distribution network. The objectives of this study were to consider connection issues relating to micro-generation from renewables and their integration into the UK distribution network. The document is divided into two sections. The first section describes the present system which includes input from micro-generation, the technical impacts and the financial considerations. The second part discusses technical, financial and governance options for the future. A summary of preferred options and recommendations is given. The study was carried out by the Halcrow Group Ltd under contract to the DTI.

Half a dollar per kWh and still cheap electricity

International Nuclear Information System (INIS)

Daey Ouwens, C.

1991-01-01

An analysis for the costs of electricity produced by an autonomous solar cell system in combination with efficient electric appliances, as they are used in houses and small offices, is presented. If efficient appliances are used, an average household will use about 700 kWh per year, compared to about 3000 kWh it is using on average at present. Efficient appliances, however, are more expensive. The extra cost per kWh saved is about the same as the cost of the fuel needed to produce a kWh in a power plant. The 700 kWh per year can be produced by an autonomous solar cell system with an area of 3 m 2 (efficiency 19%). The analysis is valid roughly for the area between 40 o northern and southern latitude. A comparison has been made between the total costs of a grid connection and the costs of an autonomous solar cell system. If all costs are capitalized and compiled, a grid connection will amount to about $6,000 (fuel costs are not included). The costs of a solar cell system producing 700 kWh per year are about the same or even lower. The modular nature of solar cell systems makes it possible to start with a certain number of appliances, depending on the amount of money one can spend. 6 tabs., 2 refs

Economic analysis of electric heating based on critical electricity price

Science.gov (United States)

Xie, Feng; Sun, Zhijie; Zhou, Xinnan; Fu, Chengran; Yang, Jie

2018-06-01

The State Grid Corporation of China proposes an alternative energy strategy, which will make electric heating an important task in the field of residential electricity consumption. This article takes this as the background, has made the detailed introduction to the inhabitant electric heating technology, and take the Zhangjiakou electric panels heating technology as an example, from the expense angle, has carried on the analysis to the electric panels heating economy. In the field of residential heating, electric panels operating costs less than gas boilers. After customers implying energy-saving behavior, electric panels operating cost is even lower than coal-fired boilers. The critical price is higher than the execution price, which indicates that the economic performance of the electric panels is significantly higher than that of the coal boiler.

Electrical swing adsorption gas storage and delivery system

Science.gov (United States)

Judkins, Roddie R.; Burchell, Timothy D.

1999-01-01

Systems and methods for electrical swing natural gas adsorption are described. An apparatus includes a pressure vessel; an electrically conductive gas adsorptive material located within the pressure vessel; and an electric power supply electrically connected to said adsorptive material. The adsorptive material can be a carbon fiber composite molecular sieve (CFCMS). The systems and methods provide advantages in that both a high energy density and a high ratio of delivered to stored gas are provided.

Relay protection features of frequency-adjustable electric drive

Science.gov (United States)

Kuprienko, V. V.

2018-03-01

The features of relay protection of high-voltage electric motors in composition of the frequency-adjustable electric drive are considered in the article. The influence of frequency converters on the stability of the operation of various types of relay protection used on electric motors is noted. Variants of circuits for connecting relay protection devices are suggested. The need to develop special relay protection devices for a frequency-adjustable electric drive is substantiated.

Making connections and thinking through emotions: between geography and psychotherapy

OpenAIRE

Bondi, Liz

2005-01-01

The current upsurge of interest in emotions within geography has the potential to contribute to critical perspectives that question conventional limits to scholarship. Three precursors of emotional geographies are discussed in this context (humanistic, feminist and non-representational geographies). Connections between emotional geographies and psychotherapy are explored with a view to resisting the equation of emotion with individualised subjective experience, and developing s...

Photovoltaic systems connected to electric power like distributed generators: the recent situation at the PVPS-IEA and at the Brazilian scenario; Sistemas fotovoltaicos conectados a rede eletrica como geradores distribuidos: a situacao recente no PVPS-IEA e no cenario brasileiro

Energy Technology Data Exchange (ETDEWEB)

Quaglia, Renato Brito; Oliveira, Sergio Henrique Ferreira de [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil). Centro de Engenharia, Modelagem e Ciencias Sociais Aplicadas. Programa de Pos-Graduacao em Energia], email: renato.quaglia@ufabc.edu.br

2008-07-01

In this paper it is considered the use of Distributed Generation (GD) as a further option to centralized generation of electricity and treats its photovoltaic systems connected to power network (SFCR's) technology as an option in this interesting 'new' model to plan the expansion of the brazilian electrical energy matrix, mainly in urban centres. For this reason, it was necessary to mention the main characteristics of this technology as distributed generators, and the profile of his generation when connected in homes and commercial buildings. Moreover, it presents the benefits that these systems can offer the electricity sector, society and the economy. In the study of Photovoltaic Power Systems Programme (PVPS), specifically the situation of this technology in Germany, realized that the creation of mechanisms of financial incentives provided to implement some of the main barriers associated with the integration of photovoltaic systems as distributed generators. In assessing the Brazilian context, there was the incipient photovoltaic market in the country, even taking some systems already installed, note that the vast majority are intended for studies of Research and Development. There is also the exploitation of photovoltaic systems connected to the network for use in homes, businesses or industries, probably because of the lack of incentive programs for SFCR's. Although there is a programme of incentives to Alternative Sources of Electricity - Proinfa, it does not consider the SFCR's in its guidelines for qualification, only the wind systems, small hydroelectric plants and systems powered by biomass. Point is, therefore, the need for the creation of an energy policy that encourages the Brazilian market photovoltaic, more precisely a policy of offering incentives conditions of maturity of this technology when connected to the network - technical standards, decrease costs, creation of hand of specialized work, installation of manufacturers

Facilitating efficient augmentation of transmission networks to connect renewable energy generation: the Australian experience

International Nuclear Information System (INIS)

Wright, Glen

2012-01-01

Australia is heavily dependent on coal for electricity generation. The Renewable Energy Target has spurred growth in the utilization of renewable energy sources, with further growth expected into the future. Australia's strongest renewable energy sources are generally distant from the transmission network in resource ‘basins’. Investment is needed to augment the transmission network to enable delivery of electricity from these sources to consumers. Considerable economies of scale flow from anticipating the connection of numerous generators in an area over time and sizing augmentations accordingly. Following a lengthy rulemaking process, the National Electricity Rules were recently amended by a new rule, designed to facilitate the construction of such efficiently sized augmentations. However, the new rule is more conservative than initially envisaged, making little substantive change to the current frameworks for augmentation and connection. This paper outlines these frameworks and the rulemaking process and identifies the key debates surrounding the rule change are identified. This paper then provides a detailed analysis of the new rule, concluding that it is defective in a number of respects and is unlikely to result in the efficient and timely augmentation of the network needed to unlock the potential of Australia's strongest renewable energy resources. - Highlights: ► Remoteness of renewable energy sources is a barrier to greater renewable energy utilization. ► Significant economies of scale flow from efficiently-sized transmission network augmentation. ► Current frameworks in Australia do not incentivise efficiently-sized network augmentations. ► The lack of property rights in an augmentation is particularly problematic. ► The new Scale Efficient Network Extensions rule is not apt to facilitate efficiently-sized network augmentations.

Simple clamped connection for bamboo truss systems

NARCIS (Netherlands)

Blok, R.

2016-01-01

“How to make fast and simple tension connections for truss systems?” The Solution: The innovation is a connection that uses only widely available base components (boltsand threaded steel bars) and simple hand tools to install it. With a handsaw and aspanner, the bamboo stems can be combined into to

Photovoltaic electricity production of a grid-connected urban house in Serbia

International Nuclear Information System (INIS)

Bojic, Milorad; Blagojevic, Mirko

2006-01-01

A technically attractive solution for sustainable present and future is to integrate photovoltaic (PV) panels into building fabric of urban houses as an alternative to grid electricity, however, in Serbia this technology is rarely applied. To contribute to sustainability and create success conditions for renewable energy sources (RES) applications due its wish to join EU, Serbian government currently integrated RES into its new energy policy framework. In the near future in the separate law, the government will identify financial conditions to apply this policy and start RES use. To adequately inform this law, we calculated the electricity revenue during entire life of a two-floor house in Belgrade, Serbia and investment in PV panels (currently available on Serbian market) integrated in its entire envelope. It was discussed what are the current degree of economic viability of this solution and suggested level of state subventions needed to support the solar electricity production either by feed-in tariffs or other financial instruments

Approach to Multi-Criteria Group Decision-Making Problems Based on the Best-Worst-Method and ELECTRE Method

Directory of Open Access Journals (Sweden)

Xinshang You

2016-09-01

Full Text Available This paper proposes a novel approach to cope with the multi-criteria group decision-making problems. We give the pairwise comparisons based on the best-worst-method (BWM, which can decrease comparison times. Additionally, our comparison results are determined with the positive and negative aspects. In order to deal with the decision matrices effectively, we consider the elimination and choice translation reality (ELECTRE III method under the intuitionistic multiplicative preference relations environment. The ELECTRE III method is designed for a double-automatic system. Under a certain limitation, without bothering the decision-makers to reevaluate the alternatives, this system can adjust some special elements that have the most influence on the group’s satisfaction degree. Moreover, the proposed method is suitable for both the intuitionistic multiplicative preference relation and the interval valued fuzzy preference relations through the transformation formula. An illustrative example is followed to demonstrate the rationality and availability of the novel method.

AutoCAD electrical 2013 for electrical control designers

CERN Document Server

Tickoo, Sham; CADCIM Technologies

2013-01-01

The AutoCAD Electrical 2013 for Electrical Control Designers textbook has been written to assist the engineering students and the practicing designers learn the application of various AutoCAD Electrical tools and options for creating electrical control designs. After reading this textbook, the users will be able to create professional electrical-control drawings easily and effectively. Moreover, the users will be able to automate various control engineering tasks such as building circuits, numbering wires, creating bills of materials, and many more. The textbook takes the users across a wide spectrum of electrical control drawings through progressive examples and numerous illustrations and exercises, thereby making it an ideal guide for both the novice and the advanced users. Salient Features of the Textbook Consists of 14 chapters that are organized in a pedagogical sequence covering various tools and features of AutoCAD Electrical such as schematic drawings, parametric and non-parametric PLC modules, Circu...

Renewable Electric Plant Information System user interface manual: Paradox 7 Runtime for Windows

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-11-01

The Renewable Electric Plant Information System (REPiS) is a comprehensive database with detailed information on grid-connected renewable electric plants in the US. The current version, REPiS3 beta, was developed in Paradox for Windows. The user interface (UI) was developed to facilitate easy access to information in the database, without the need to have, or know how to use, Paradox for Windows. The UI is designed to provide quick responses to commonly requested sorts of the database. A quick perusal of this manual will familiarize one with the functions of the UI and will make use of the system easier. There are six parts to this manual: (1) Quick Start: Instructions for Users Familiar with Database Applications; (2) Getting Started: The Installation Process; (3) Choosing the Appropriate Report; (4) Using the User Interface; (5) Troubleshooting; (6) Appendices A and B.

New Brunswick electricity market rules : summary

International Nuclear Information System (INIS)

2004-02-01

The electricity market rules for New Brunswick were reviewed with particular reference to two broad classifications. The first classification is based on the roles and responsibilities of the system operator (SO) in facilitating the Bilateral Contract market, as well as the role of market participants in participating in the Bilateral Contract market. The second classification is based on the roles and responsibilities of each of the SO, market participants and transmitters in maintaining the reliability of the integrated electricity system and ensuring a secure supply of electricity for consumers in New Brunswick. The market rules consist of 10 chapters entitled: (1) introduction to the market rules and administrative rules of general application, (2) market participation and the use of the SO-controlled grid, (3) market administration, (4) technical and connection requirements, testing and commissioning, (5) system reliability, (6) operational requirements, (7) settlement, (8) connection of new or modified facilities, (9) transmission system planning, investment and operation, and (10) definitions and interpretation

Electricity generating system. [Wind/diesel/flywheel system

Energy Technology Data Exchange (ETDEWEB)

Moody, R.L.

1992-02-05

An electricity generating system is described which includes a water tank with electric heating elements connected to the water cooling system of a diesel engine which is heated by excess output of the system. Power in excess of that required by a load which is generated by a wind turbine driven generator runs up a flywheel and further excess is absorbed in the tank. A fan associated with a radiator connected to the tank may be operated to dissipate further excess power. When the load requirements exceed the output of the generators linked to the wind turbine and the flywheel the engine operates a synchronous alternator. (author).

The decision making of an electric power producer

International Nuclear Information System (INIS)

Giger, F.

2002-01-01

How can choose an electric power producer when he has to decide an investment of a supplementary power plant? Which were the criteria to choose a small or a medium power reactor? In this framework, the economical profitability, the technical feasibility and the associated risks are discussed. (A.L.B.)

Mini-biomass electric generation

Energy Technology Data Exchange (ETDEWEB)

Elliot, G. [International Applied Engineering, Inc., Atlanta, GA (United States)

1997-12-01

Awareness of the living standards achieved by others has resulted in a Russian population which is yearning for a higher standard of living. Such a situation demands access to affordable electricity in remote areas. Remote energy requirements creates the need to transport power or fossil fuels over long distances. Application of local renewable energy resources could eliminate the need for and costs of long distance power supply. Vast forest resources spread over most of Russia make biomass an ideal renewable energy candidate for many off-grid villages. The primary objective for this preliminary evaluation is to examine the economic feasibility of replacing distillate and gasoline fuels with local waste biomass as the primary fuel for village energy in outlying regions of Russia. Approximately 20 million people live in regions where Russia`s Unified Electric System grid does not penetrate. Most of these people are connected to smaller independent power grids, but approximately 8 million Russians live in off-grid villages and small towns served by stand-alone generation systems using either diesel fuel or gasoline. The off-grid villages depend on expensive distillate fuels and gasoline for combustion in small boilers and engines. These fuels are used for both electricity generation and district heating. Typically, diesel generator systems with a capacity of up to 1 MW serve a collective farm, settlement and their rural enterprises (there are an estimated 10,000 such systems in Russia). Smaller gasoline-fueled generator systems with capacities in the range of 0.5 - 5 kW serve smaller farms or rural enterprises (there are about 60,000 such systems in Russia).

Designing a New Electricity Consumer

DEFF Research Database (Denmark)

Pallesen, Trine; Jenle, Rasmus Ploug

The paper reports on a smart grid experiment for the making of a new retail electricity market integrating fluctuating electricity generation into electricity systems. An outline of design challenges faced by the market engineers when dealing with different and lacking conceptions of consumers...

Electricity and the environment

International Nuclear Information System (INIS)

1991-09-01

The objective of the Symposium was to provide a comprehensive assessment of the environmental and health factors as well as the economic factors involved in supplying electricity services, and to suggest a framework within which these issues should be taken into account in making future plans and decisions on electricity production and use. The potential role of different ways of meeting electricity service requirements was also to be analysed, taking into consideration both demand side and supply side options in the light of their comparative economic, environmental and health related impacts. Four Expert Groups considered key issues: the environmental implications of energy and electricity supply and demand; energy sources and technologies for electricity generation; comparative environmental and health effects of different energy systems for electricity generation; and the incorporation of environmental and health impacts into policy, planning and decision making for the electricity sector. During the Symposium, keynote addresses and invited papers presented by leading experts and policy makers provided additional related information. In this volume the background papers are presented. The proceedings have been published separately, and the individual papers in both volumes have been indexed separately for INIS. Refs, figs and tabs

A Wind Farm Electrical Systems Evaluation with EeFarm-II

Directory of Open Access Journals (Sweden)

Jan Pierik

2010-03-01

Full Text Available EeFarm-II is used to evaluate 13 different electrical systems for a 200 MW wind farm with a 100 km connection to shore. The evaluation is based on component manufacturer data of 2009. AC systems are compared to systems with DC connections inside the wind farm and DC connection to shore. Two options have the best performance for this wind farm size and distance: the AC system and the system with a DC connection to shore. EeFarm-II is a user friendly computer program for wind farm electrical and economic evaluation. It has been built as a Simulink Library in the graphical interface of Matlab-Simulink. EeFarm-II contains models of wind turbines, generators, transformers, AC cables, inductors, nodes, splitters, PWM converters, thyristor converters, DC cables, choppers and statcoms.

The connection-set algebra--a novel formalism for the representation of connectivity structure in neuronal network models.

Science.gov (United States)

Djurfeldt, Mikael

2012-07-01

The connection-set algebra (CSA) is a novel and general formalism for the description of connectivity in neuronal network models, from small-scale to large-scale structure. The algebra provides operators to form more complex sets of connections from simpler ones and also provides parameterization of such sets. CSA is expressive enough to describe a wide range of connection patterns, including multiple types of random and/or geometrically dependent connectivity, and can serve as a concise notation for network structure in scientific writing. CSA implementations allow for scalable and efficient representation of connectivity in parallel neuronal network simulators and could even allow for avoiding explicit representation of connections in computer memory. The expressiveness of CSA makes prototyping of network structure easy. A C+ + version of the algebra has been implemented and used in a large-scale neuronal network simulation (Djurfeldt et al., IBM J Res Dev 52(1/2):31-42, 2008b) and an implementation in Python has been publicly released.

An encyclopedia on domestic electricity

International Nuclear Information System (INIS)

1982-12-01

This book describes the footprint of domestic electrification with domestic energy and the role of electrification, basic knowledge on domestic electrification, the basic things electric equipment in domestic, materials, part and making, demand of electricity, electrification and life, various electric equipment in the kitchen, rationalization of house chore, environment and hygiene like electric iron, electric stove, electric mat and dining wagon, beauty treatment and health, refinement and entertainment and lighting in houses.

Electricity theft: a comparative analysis

International Nuclear Information System (INIS)

Smith, T.B.

2004-01-01

Electricity theft can be in the form of fraud (meter tampering), stealing (illegal connections), billing irregularities, and unpaid bills. Estimates of the extent of electricity theft in a sample of 102 countries for 1980 and 2000 are undertaken. The evidence shows that theft is increasing in most regions of the world. The financial impacts of theft are reduced income from the sale of electricity and the necessity to charge more to consumers. Electricity theft is closely related to governance indicators, with higher levels of theft in countries without effective accountability, political instability, low government effectiveness and high levels of corruption. Electricity theft can be reduced by applying technical solutions such as tamper-proof meters, managerial methods such as inspection and monitoring, and in some cases restructuring power systems ownership and regulation

An open data repository for steady state analysis of a 100-node electricity distribution network with moderate connection of renewable energy sources.

Science.gov (United States)

Lazarou, Stavros; Vita, Vasiliki; Ekonomou, Lambros

2018-02-01

The data of this article represent a real electricity distribution network on twenty kilovolts (20 kV) at medium voltage level of the Hellenic electricity distribution system [1]. This network has been chosen as suitable for smart grid analysis. It demonstrates moderate penetration of renewable sources and it has capability in part of time for reverse power flows. It is suitable for studies of load aggregation, storage, demand response. It represents a rural line of fifty-five kilometres (55 km) total length, a typical length for this type. It serves forty-five (45) medium to low voltage transformers and twenty-four (24) connections to photovoltaic plants. The total installed load capacity is twelve mega-volt-ampere (12 MVA), however the maximum observed load is lower. The data are ready to perform load flow simulation on Matpower [2] for the maximum observed load power on the half production for renewables. The simulation results and processed data for creating the source code are also provided on the database available at http://dx.doi.org/10.7910/DVN/1I6MKU.

Dashboard: biogas for electricity production - Forth quarter 2015

International Nuclear Information System (INIS)

Cavaud, Denis; Reynaud, Didier

2016-02-01

This publication describes the situation of biogas-based electricity production in France and its evolution over the first quarters of 2015. A map indicates the level of connected power per district. Graphs illustrate the evolution of the number of new connections per quarter since 2009, the evolution of electricity quarterly production since 2011. Tables indicate the number of installations per power level (less than 0.5 MW, between 0.5 and 1.0 MW, more than 1 MW) and per installation type. Regional data are given in terms of number of installations, installed power in December 2015, regional share and evolution

Equivalence between classical and quantum dynamics. Neutral kaons and electric circuits

International Nuclear Information System (INIS)

Caruso, M.; Fanchiotti, H.; Canal, C.A. Garcia

2011-01-01

An equivalence between the Schroedinger dynamics of a quantum system with a finite number of basis states and a classical dynamics is presented. The equivalence is an isomorphism that connects in univocal way both dynamical systems. We treat the particular case of neutral kaons and found a class of electric networks uniquely related to the kaon system finding the complete map between the matrix elements of the effective Hamiltonian of kaons and those elements of the classical dynamics of the networks. As a consequence, the relevant ε parameter that measures CP violation in the kaon system is completely determined in terms of network parameters. - Highlights: → We provide a formal equivalence between classical and quantum dynamics. → We make use of the decomplexification concept. → Neutral kaon systems can be represented by electric circuits. → CP symmetry violation can be taken into account by non-reciprocity. → Non-reciprocity is represented by gyrators.

Aging evaluation of electrical circuits using the ECCAD [Electrical Circuit Characterization and Diagnostic] system

International Nuclear Information System (INIS)

Edson, J.L.

1988-01-01

As a part of the Nuclear Regulatory Commission Nuclear Plant Aging Research Program, an aging assessment of electrical circuits was conducted at the Shippingport Atomic Power Station Decommissioning Project. The objective of this work was to evaluate the effectiveness of the Electrical Circuit Characterization and Diagnostic (ECCAD) system in identifying circuit conditions, to determine the present condition of selected electrical circuits, and correlate the results with aging effects. To accomplish this task, a series of electrical tests was performed on each circuit using the ECCAD system, which is composed of commercially available electronic test equipment under computer control. Test results indicate that the ECCAD system is effective in detecting and identifying aging and service wear in selected electrical circuits. The major area of degradation in the circuits tested was at the termination/connection points, whereas the cables were in generally good condition

Hybrid system power generation'wind-photovoltaic' connected to the ...

African Journals Online (AJOL)

Hybrid system power generation'wind-photovoltaic' connected to the ... from Hybrid System, power delivered to or from grid and phase voltage of the inverter leg. ... Renewable Energy, Electrical Network 220 kV, Hybrid System, Solar, MPPT.

The investigation of a compact auto-connected wire-wrapped pulsed transformer.

Science.gov (United States)

Wang, Yuwei; Zhang, Jiande; Chen, Dongqun; Cao, Shengguang; Li, Da; Zhang, Tianyang

2012-05-01

For the power conditioning circuit used to deliver power efficiently from flux compression generator (FCG) to the load with high impedance, an air-cored and wire-wrapped transformer convenient in coaxial connection to the other parts is investigated. To reduce the size and enhance the performance, an auto-connection is adopted. A fast and simple model is used to calculate the electrical parameters of the transformer. To evaluate the high voltage capability, the voltages across turns and the electric field distribution in the transformer are investigated. The calculated and the measured electrical parameters of the transformer show good agreements. And the safe operating voltage is predicted to exceed 500 kV. In the preliminary experiments, the transformer is tested in a power conditioning circuit with a capacitive power supply. It is demonstrated that the output voltage of the transformer reaches -342 kV under the input voltage of -81 kV.

Connecting Worlds: Interculturality, Identity and Multilingual Digital Stories in the Making

Science.gov (United States)

Anderson, Jim; Macleroy, Vicky

2017-01-01

Based on findings from a 5-year research project called "Critical Connections", this article sets out an integrated framework for language learning in the context of multilingual digital storytelling. Following an explanation of the theoretical approach, four vignettes are presented which illustrate the principles in practice.…

Landfill Gas Electricity Project Interconnection Webinar

Science.gov (United States)

This page contains information about a webinar LMOP offered to LMOP Partners to address questions associated with connecting electricity generating systems to the grid during LFG energy project planning and implementation.

Electricity transmission pricing: Tracing based point-of-connection tariff

International Nuclear Information System (INIS)

Abhyankar, A.R.; Khaparde, S.A.

2009-01-01

Point-of-connection (POC) scheme of transmission pricing in decentralized markets charges the participants a single rate per MW depending on their point-of-connection. Use of grossly aggregated postage stamp rates as POC charges fails to provide appropriate price signals. The POC tariff based on distribution of network sunk costs by employing conventional tracing assures recovery of sunk costs based on extent of use of network by participants. However, the POC tariff by this method does not accommodate economically efficient price signals which correspond to marginal costs. On the other hand, the POC tariff, if made proportional to marginal costs alone, fails to account for sunk costs and extent of use of network. This paper overcomes these lacunae by combining the above stated desired objectives under the recently proposed optimal tracing framework. Since real power tracing problem is amenable to multiple solutions, it is formulated as linearly constrained optimization problem. By employing this methodology, consideration of extent of network use and sunk cost recovery are guaranteed, while objective function is designed such that the spatial pattern of price signals closely follows the pattern of scaled locational marginal prices. The methodology is tested on IEEE 30 bus system, wherein average power flow pattern is established by running various simulation states on congested and un-congested network conditions. (author)

Costs of the grid connection of wind turbines

Energy Technology Data Exchange (ETDEWEB)

Siden, G [Halmstad Univ. (Sweden)

1996-12-31

The costs of the grid connection of wind turbines in Sweden have until now been about 5 % of the total investments, provided that the distance of the connection cable is limited. Now the grid will soon be filled locally and it will be necessary to strengthen it. The costs for this can also be about 5 %, and the total cost about 10 %. Improvements in the electrical systems of the wind turbines and the connection technique can give less disturbance in the grid and diminish the costs. It is important to agree on how to share the costs for strengthening the grid. Otherwise, it can become an obstacle when building new wind turbines. (author)

Costs of the grid connection of wind turbines

International Nuclear Information System (INIS)

Siden, G.

1995-01-01

The costs of the grid connection of wind turbines in Sweden have until now been about 5 % of the total investments, provided that the distance of the connection cable is limited. Now the grid will soon be filled locally and it will be necessary to strengthen it. The costs for this can also be about 5 %, and the total cost about 10 %. Improvements in the electrical systems of the wind turbines and the connection technique can give less disturbance in the grid and diminish the costs. It is important to agree on how to share the costs for strengthening the grid. Otherwise, it can become an obstacle when building new wind turbines. (author)

Costs of the grid connection of wind turbines

Energy Technology Data Exchange (ETDEWEB)

Siden, G. [Halmstad Univ. (Sweden)

1995-12-31

The costs of the grid connection of wind turbines in Sweden have until now been about 5 % of the total investments, provided that the distance of the connection cable is limited. Now the grid will soon be filled locally and it will be necessary to strengthen it. The costs for this can also be about 5 %, and the total cost about 10 %. Improvements in the electrical systems of the wind turbines and the connection technique can give less disturbance in the grid and diminish the costs. It is important to agree on how to share the costs for strengthening the grid. Otherwise, it can become an obstacle when building new wind turbines. (author)

Aberrant orbitofrontal connectivity in marijuana smoking adolescents

Directory of Open Access Journals (Sweden)

Melissa Patricia Lopez-Larson

2015-12-01

Discussion: Findings indicate atypical OFC functional connectivity patterns in attentional/executive, motor and reward networks in adolescents with heavy MJ use. These anomalies may be related to suboptimal decision making capacities and increased impulsivity. Results also suggest different OFC connectivity patterns may be present in adolescents with early onset of MJ use and high lifetime exposure to MJ.

7 CFR 1700.28 - Electric Program.

Science.gov (United States)

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Electric Program. 1700.28 Section 1700.28 Agriculture... GENERAL INFORMATION Agency Organization and Functions § 1700.28 Electric Program. RUS, through the Electric Program, makes loans and loan guarantees for rural electrification and the furnishing of electric...

A Wind Farm Electrical Systems Evaluation with EeFarm-II

NARCIS (Netherlands)

Pierik, J.; Axelsson, U.; Eriksson, E.; Salomonsson, D.; Bauer, P.; Czech, B.

2010-01-01

EeFarm-II is used to evaluate 13 different electrical systems for a 200 MW wind farm with a 100 km connection to shore. The evaluation is based on component manufacturer data of 2009. AC systems are compared to systems with DC connections inside the wind farm and DC connection to shore. Two options

Risk perception and strategic decision making :general insights, a framework, and specific application to electricity generation using nuclear energy

International Nuclear Information System (INIS)

Brewer, Jeffrey D.

2005-01-01

The objective of this report is to promote increased understanding of decision making processes and hopefully to enable improved decision making regarding high-consequence, highly sophisticated technological systems. This report brings together insights regarding risk perception and decision making across domains ranging from nuclear power technology safety, cognitive psychology, economics, science education, public policy, and neural science (to name a few). It forms them into a unique, coherent, concise framework, and list of strategies to aid in decision making. It is suggested that all decision makers, whether ordinary citizens, academics, or political leaders, ought to cultivate their abilities to separate the wheat from the chaff in these types of decision making instances. The wheat includes proper data sources and helpful human decision making heuristics; these should be sought. The chaff includes ''unhelpful biases'' that hinder proper interpretation of available data and lead people unwittingly toward inappropriate decision making ''strategies''; obviously, these should be avoided. It is further proposed that successfully accomplishing the wheat vs. chaff separation is very difficult, yet tenable. This report hopes to expose and facilitate navigation away from decision-making traps which often ensnare the unwary. Furthermore, it is emphasized that one's personal decision making biases can be examined, and tools can be provided allowing better means to generate, evaluate, and select among decision options. Many examples in this report are tailored to the energy domain (esp. nuclear power for electricity generation). The decision making framework and approach presented here are applicable to any high-consequence, highly sophisticated technological system

Peripheral and subversive: Women making connections and challenging the boundaries of the science community

Science.gov (United States)

Davis, Kathleen S.

2001-07-01

Researchers continue to report the underrepresentation of females in the science professions (AAUW, 1992; NSF, 1999; Vetter, 1992). Investigators have illuminated many factors that contribute to the insider status in the science community of some groups and the peripheral/outsider status of women and girls (Brickhouse, 1994; Delamont, 1989; Harding, 1991; Schiebinger, 1989). Some research has shown that supportive science networks have had a positive influence on women's participation and retention in science practices (AAUW, 1992; Keith & Keith, 1989; Kreinberg & Lewis, 1996; Varanka-Martin, 1996). In order to provide a better understanding of the role social capital plays in women's legitimate participation in science, I draw upon the findings of a qualitative study that examines the valued capital, ways, and practices of a support group for women working in the sciences at an academic research institution. Findings from this study indicate how women 1) were given little access to powerful networks in science that would provide them with opportunities to acquire the knowledge, skills, and resources necessary to be legitimate in the traditional sense, and 2) encountered many obstacles in their attempts to develop networks and make such connections between themselves and other women. Findings also indicate that, despite these impediments, the support group provided a meaningful and resourceful network through which they developed a critical perspective of legitimacy as they sought to make explicit the culture of science. Participants not only employed the traditional methods of scientific inquiry, but also acknowledged and valued the voices and experiences of those from nondominant groups. They constructed a new discourse that was inclusive of diverse voices, created new career pathways, and developed a vision of mentoring that facilitated females' development of a critical view of the science community and their legitimate participation.

Development needs of the electricity market. Final report by the working group on the five-year revision of the electricity market act

International Nuclear Information System (INIS)

2001-01-01

The opening of the Finnish electricity market was started by the Electricity Market Act that entered into force in 1995. The Act abolished the obstructions to competition in electricity production, foreign trade and sales. To guarantee the functioning of the electricity market in practice, the electricity network operators were obliged to gradually open up their networks for the use of other parties operating on the market. Finland has liberated her electricity market in the forefront and ahead of the prescribed time in relation to the obligations laid down in the EC Directive concerning common rules for the internal market in electricity. The working group has studied the development needs of the electricity market in the light of experience gained during the validity of the Electricity Market Act. As a general conclusion, the working group states that the Finnish electricity market is functioning in an appropriate manner and that there is no reason to essentially change the model chosen for the opening of the electricity market. The working group makes several proposals for actions and recommendations for improving the efficiency of the electricity market. According to the view of the working group, electricity users, production plants and distribution network operators should be authorised to construct a 110-440 kV connection line of their own to a 110 kV network or grid. Following the working group's proposal, the regulation concerning electricity retailers would be extended over to electricity vendors operating as retailers in a real-estate network. To guarantee the functioning of competition on the small-scale consumers' electricity market, the working group suggests that the customers would be entitled during one year to one change of vendor for which no separate fee would be collected. The working group proposes that construction authorisation conditions pertaining to border lines should be specified so that one condition for granting an authorisation would

Brain Functional Connectivity in MS: An EEG-NIRS Study

Science.gov (United States)

2015-10-01

1 AWARD NUMBER: W81XWH-14-1-0582 TITLE: Brain Functional Connectivity in MS: An EEG -NIRS Study PRINCIPAL INVESTIGATOR: Heather Wishart...Functional Connectivity in MS: An EEG -NIRS Study 5b. GRANT NUMBER W81XWH-14-1-0582 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Heather...electrical ( EEG ) and blood volume and blood oxygen-based (NIRS and fMRI) signals, and to use the results to help optimize blood oxygen level

Experimental study on the connection property of full-scale composite member

Science.gov (United States)

Panpan, Cao; Qing, Sun

2018-01-01

The excellent properties of composite result in its increasingly application in electric power construction, however there are less experimental studies on full-scale composite member connection property. Full-scale experiments of the connection property between E-glass fiber/epoxy reinforced polymer member and steel casing in practical engineering have been conducted. Based on the axial compression test of the designed specimens, the failure process and failure characteristics were observed, the load-displacement curves and strain distribution of the specimens were obtained. The finite element analysis was used to get the tensile connection strength of the component. The connection property of the components was analyzed to provide basis of the casing connection of GFRP application in practical engineering.

The Impact of Transformer Winding Connections of A Grid-Connected PV on Voltage Quality Improvement

Energy Technology Data Exchange (ETDEWEB)

Muljadi, Eduard [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tumbelaka, Hanny H. [Petra Christian University; Gao, Wenzhong [University of Denver

2018-03-01

In this paper, the high-power PV plant is connected to the weak grid by means of a three-phase power transformer. The selection of transformer winding connection is critical especially when the PV inverter has a reactive power controller. In general, transformer winding connection can be arranged in star-star (with neutral earthed) or star-delta. The reactive power controller supports voltage regulation of the power system particularly under transient faults. Its control strategy is based on utilizing the grid currents to make a three-phase reactive unbalanced current with a small gain. The gain is determined by the system impedance. Simulation results exhibit that the control strategy works very well particularly under disturbance conditions when the transformer winding connection is star-star with both neutrals grounded. The power quality in terms of the voltage quality is improved.

Advanced simulation of windmills in electric power supply

DEFF Research Database (Denmark)

Akhmatov, Vladislav; Knudsen, Hans; Nielsen, Arne Hejde

2000-01-01

-connected windmills as a part of realistic electrical grid models. That means an arbitrary number of wind farms or single windmills within an arbitrary network configuration. The windmill model may be applied to study of electric power system stability and of power quality as well. It is found that a grid...

Impact of connection density on regional cost differences for network operators in the Netherlands

International Nuclear Information System (INIS)

2009-04-01

The Dutch Office of Energy Regulation ('Energiekamer') has an obligation to investigate the extent to which the electricity and gas distribution businesses (DNOs) in the Netherlands face different structural environments that result in regional cost differences which, in turn, could justify tariff differences. On the basis of previous studies, Energiekamer has identified 'water crossings' and 'local taxes' as allowable regional differences. To account for them, Energiekamer has introduced an adjustment to the regulated revenues formula in order to guarantee a level-playing field to the Dutch DNOs. In addition to these factors, it has been claimed that connection density may have an impact on distribution costs and that, therefore, regulated revenues should be adjusted to compensate for regional differences in connection density between DNOs. However, so far, the research in this field has been unable to identify a sufficiently robust relationship between cost and connection density to support this claim. In order to address this issue, Energiekamer has asked Frontier Economics and Consentec to further investigate the relationship between connection density and distribution costs in the Netherlands. Therefore, our analysis has aimed at determining whether, and to what extent, connection density in the Netherlands is a significant driver of the costs of electricity and gas distribution networks. The following three questions are answered: (1) Is connection density a significant cost driver in electricity and gas networks in the Netherlands?; (2) If so, which functional form (e.g. U-shaped) does this relationship have in the Netherlands?; (3) Finally, based on the evidence collected, is the influence of connection density sufficiently well-determined to be considered a regional difference in the Dutch regulatory framework?

Renewable Energy Jobs. Status, prospects and policies. Biofuels and grid-connected electricity generation

Energy Technology Data Exchange (ETDEWEB)

Lucas, H; Ferroukhi, R [et al.; IRENA Policy Advisory Services and Capacity Building Directorate, Abu Dhabi (United Arab Emirates)

2012-01-15

Over the past years, interest has grown in the potential for the renewable energy industry to create jobs. Governments are seeking win-win solutions to the dual challenge of high unemployment and climate change. By 2010, USD 51 billion had been pledged to renewables in stimulus packages, and by early 2011 there were 119 countries with some kind of policy target and/or support policy for renewable energy, such as feed-in tariffs, quota obligations, favourable tax treatment and public loans or grants, many of which explicitly target job creation as a policy goal. Policy-makers in many countries are now designing renewable energy policies that aim to create new jobs, build industries and benefit particular geographic areas. But how much do we know for certain about the job creation potential for renewable energy? This working paper aims to provide an overview of current knowledge on five questions: (1) How can jobs in renewable energy be characterised?; (2) How are they shared out across the technology value chain and what skill levels are required?; (3) How many jobs currently exist and where are they in the world?; (4) How many renewable energy jobs could there be in the future?; and (5) What policy frameworks can be used to promote employment benefits from renewable energy? This paper focuses on grid-connected electricity generation technologies and biofuels. Since the employment potential of off-grid applications is large, it will be covered by a forthcoming study by IRENA on job creation in the context of energy access, based on a number of case studies.

Electricity and the environment

International Nuclear Information System (INIS)

1991-01-01

The objective of the Symposium was to provide a comprehensive assessment of the environmental and health factors as well as the economic factors involved in supplying electricity services, and to suggest a framework within which these issues should be taken into account in making future plans and decisions on electricity production and use. The potential role of different ways of meeting electricity service requirements was also to be analysed, taking into consideration both demand side and supply side options in the light of their comparative economic, environmental and health related impacts. Four Expert Groups considered key issues: the environmental implications of energy and electricity supply and demand; energy sources and technologies for electricity generation; comparative environmental and health effects of different energy systems for electricity generation; and the incorporation of environmental and health impacts into policy, planning and decision making for the electricity sector. During the Symposium, keynote addresses and invited papers presented by leading experts and policy makers provided additional related information. The Proceedings contain all the addresses and papers presented (which are also indexed separately) together with summaries of the discussions that took place. The Key Issues Papers are presented in a separate publication. Refs, figs and tabs

PLL strategies of grid connected converters under distorted input voltages

Czech Academy of Sciences Publication Activity Database

Šimek, Petr; Škramlík, Jiří; Valouch, Viktor

2014-01-01

Roč. 59, č. 1 (2014), s. 1-12 ISSN 0001-7043 Institutional support: RVO:61388998 Keywords : voltage source converter * grid - connected applications * phase locked loop Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

On electric vehicle battery charger modeling

OpenAIRE

Sainz Sapera, Luis; Mesas García, Juan José; Balcells Sendra, Josep

2011-01-01

The increase of electric vehicle (EV) battery chargers connected to electric networks could lead to future harmonic problems in power systems. These loads are nonlinear devices that inject harmonic currents and pollute network voltages. Thus, battery charger modeling must be studied in detail to determine their harmonic emissions and prevent future problems. This paper investigates EV battery charger behavior, analyzes its equivalent circuit and reports a model for each ...

Hydrologic connectivity in the McMurdo Dry Valleys of Antarctica: System function and changes over two decades

Science.gov (United States)

Wlostowski, A. N.; Gooseff, M. N.; Bernzott, E. D.; McKnight, D. M.; Jaros, C.; Lyons, W.

2013-12-01

The McMurdo Dry Valleys of Antarctica is one of the coldest (average annual air temperature of -18°C) and driest (ecological connections in the McMurdo Dry Valleys. Intermittent glacial meltwater streams connect glaciers to closed basin lakes and compose the most prominent hydrologic nexus in the valleys. This study uses of 20+ years of stream temperature, electrical conductivity (EC), and discharge data to enhance our quantitative understanding of the temporal dynamics of hydrologic connections along the glacier-stream-lake continuum. Annually, streamflow occurs for a relatively brief 10-12 week period of the austral summer. Longer streams are more prone to intermittent dry periods during the flow season, making for a harsher ecological environment than shorter streams. Diurnal streamflow variation occurs primarily as a result of changing solar postion relative to the source-glacier surfaces. Therfore, different streams predictably experience high flows and low flows at different times of the day. Electrical conductivity also exhibits diel variations, but the nature of EC-discharge relationships differs among streams throughout the valley. Longer streams have higher EC values and lower discharges than shorter streams, suggesting that hyporheic zones act as a significant solute source and hydrologic reservoir along longer streams. Water temperatures are consistently warmer in longer streams, relative to shorter streams, likely due to prolonged exposure to incident radiation with longer surface water residence times. Inter-annually, several shorter streams in the region show significant increases in Q10, Q30, Q50, Q70, Q90, and/or Q100 flows across the 20+ year record, indicating a long-term non-stationarity in hydrologic system dynamics. The tight coupling between surface waters and the glacier surface energy balance bring forth remarkably consistent hydrologic patterns on the daily and annual timescales, providing a model system for understanding fundamental

Making connections: Case studies of interconnection barriers and their impact on distributed power projects

Energy Technology Data Exchange (ETDEWEB)

Alderfer, B.; Eldridge, M.; Starrs, T.

2000-07-25

Distributed power is modular electric generation or storage located close to the point of use. Based on interviews of distributed generation project proponents, this report reviews the barriers that distributed generators of electricity are encountering when attempting to interconnect to the electrical grid. Descriptions of 26 of 65 case studies are included in the report. The survey found and the report describes a wide range of technical, business-practice, and regulatory barriers to interconnection. An action plan for reducing the impact of these barriers is also included.

46 CFR 28.870 - Emergency source of electrical power.

Science.gov (United States)

2010-10-01

.... (a) The following electrical loads must be connected to an independent emergency source of power capable of supplying all connected loads continuously for at least three hours: (1) Navigation lights; (2... ventilated compartment. The batteries must be protected from falling objects; (4) Each battery tray must be...

Optimising the economic viability of grid-connected photovoltaic systems

International Nuclear Information System (INIS)

Mondol, Jayanta Deb; Yohanis, Yigzaw G; Norton, Brian

2009-01-01

The impact of photovoltaic (PV) array size, orientation, inclination, load profile, electricity buying price, feed-in tariffs, PV/inverter sizing ratio ('sizing ratio') and PV/inverter cost ratio ('cost ratio') on the economic viability of a grid-connected PV system was investigated using a validated TRNSYS simulation model. The results showed that the fractional load met directly by a PV system depends on matching between PV supply and building load profile, sizing ratio and PV inclination. The profitability of a grid-connected PV system increases if the PV system is sized to reduce excess PV electrical energy fed to the grid when the feed-in tariff is lower than electricity buying price. The effect of feed-in tariffs on PV saving for selected European countries has been shown. The cost of the PV electricity depends on sizing ratio, PV and inverter lifetimes, cost ratio, PV inclination and financial parameters. The effect of cost ratio on the optimum PV/inverter sizing ratio is less significant when the cost ratio lies within 7-11. The minimum PV electricity cost at low and high insolation conditions were obtained for sizing ratios of 1.6 and 1.2, respectively. The lowest PV electricity cost was found for surface slopes within 30-40 for the selected European locations. The PV electricity cost for cost ratio of 5 and 13 varied from 0.44-0.85 EURkWh -1 to 0.38-0.76 EURkWh -1 , respectively within high to low insolation conditions when the PV module unit cost, market discount rate, PV size, PV lifetime and inverter lifetime were assumed to be 6.5 EURW p -1 , 3%, 13 kW p , 20 years and 10 years, respectively. (author)

The Study on Hybrid Multi-Infeed HVDC System Connecting with Offshore Wind Farm

DEFF Research Database (Denmark)

Liu, Yan

furnish the VSC-HVDC connected wind farm with a fast and reliable LVRT ability. The voltage fluctuation caused by the intermittent wind power is another important challenge to the system stability. As in the case of the LCC-HVDC links, their stable operations are highly dependent on the AC side voltage...... with the short electrical distance. And consequently, a so-called Multi-Infeed Direct Current (MIDC) transmission system is formed. On the other hand, as the fast growing of wind power in electrical grids, the Voltage Source Converter based HVDC (VSC-HVDC) links have becoming a favorable choice for connecting...

Regulated Electric Drainage and its Interference with Track Circuits

Directory of Open Access Journals (Sweden)

Vaclav Kolar

2018-01-01

Full Text Available Electric drainage is a power electronic device used to protect underground metal devices (such as piping from the corrosive effects of stray currents. Stray currents are usually caused by DC electric traction, such as trams or railways. In places where stray currents leave the underground device and return into rails, they cause significant electrochemical corrosion of buried devices. The principle of electric drainage is based on electrical connection between the underground device and electric traction rails, which ensures that current flows through this connection, instead of flowing into the ground. Nowadays, the most widely used type is regulated electric drainage, where current is regulated by means of Pulse Width Modulation (PWM. Because of this modulation, current flowing through the drainage contains harmonic components with different frequencies. In modern railways, track circuits are often used as an important part of the track security system. For safe operation, it is necessary to ensure that frequencies generated by the drainage do not interfere with track circuits. This paper describes the design of a regulated drainage control system, with regard to its compatibility with track circuits and this paper contains related computer simulations and discussion of the results

Network connection of distributed electricity production - a preliminary study

International Nuclear Information System (INIS)

Pleym, Anngjerd; Mogstad, Olve

2002-01-01

It will be necessary to lower the barriers for utilisation of distributed energy sources in order to increase the use of such sources in Norway. A relatively extensive R and D activity would be required for reaching this goal. Available Norwegian and international guidelines and technical requirements with respect to network connection of the distributed energy sources are studied with the aim of exposing needs for further R and D initiatives. A limited monitor is also carried out among the Norwegian network businesses with distributed units in their networks. The results show that the main focus in the R and D activities has drifted away from establishing guidelines for technical requirements for network coupling. Some verification work remains in investigating the usefulness of the existing international and the specific commercial network guidelines. For the network industry the main focus must be on the two following areas: 1) How will large concentrations of distributed production units connected to the same network influence the voltage quality and the delivery reliability in the networks. 2) How can the network businesses employ the distributed production units in their networks. A Nordic project (Finland, Sweden, Norway) which will study these problems is being established. Large national scientific institutions will be involved. The executive committee will consist of representatives from Finenergy, Elforsk and EBL Kompetanse and other financing institutions and industries. A Finnish business Merinova, is to be appointed to the project leadership

Vehicle electrical system state controller

Science.gov (United States)

Bissontz, Jay E.

2017-10-17

A motor vehicle electrical power distribution system includes a plurality of distribution sub-systems, an electrical power storage sub-system and a plurality of switching devices for selective connection of elements of and loads on the power distribution system to the electrical power storage sub-system. A state transition initiator provides inputs to control system operation of switching devices to change the states of the power distribution system. The state transition initiator has a plurality of positions selection of which can initiate a state transition. The state transition initiator can emulate a four position rotary ignition switch. Fail safe power cutoff switches provide high voltage switching device protection.

Two devices for atmospheric electric field measurement

International Nuclear Information System (INIS)

Colombet, Andre; Hubert, Pierre.

1977-02-01

Two instruments installed at St Privat d'Allier for electric field measurement in connection with the rocket triggered lighting experiment program are described. The first one is a radioactive probe electrometer used as a warning device. The second is a field mill used for tape recording of electric field variation during the triggering events. Typical examples of such records are given [fr

Risk limitation, safety and environmental compatibility in electricity generation

International Nuclear Information System (INIS)

Angelini, A.M.

1981-01-01

The purpose of this paper is to present the problem of meeting future electricity needs while at the same time reducing to a minimum the risks, the pollution of air and water and the environmental effects of power stations. The first resource to exploit is the ''virtual source'' represented by energy saving pursued to the limit of the possible. The second, in order of priority, is that of renewable resources as yet unused and under development. Unfortunately, in most countries these latter resources are far from sufficient: it is then necessary to choose between the use of conventional fossil fuels and nuclear fuels. In this paper it is shown that, of all the possible fossil fuels, only coal can be considered for electricity production. As a result, in meeting new electricity needs, the choice will have to be made between coal and nuclear power. Attention is directed to factors having a significant influence on this choice, particularly the risks and safety problems in the widest sense, with a view to making a global evaluation comprising not just generating stations but the entire production cycle, from the search for the primary source to the supplying of electricity to the user. The most important problems that arise in this connection are briefly analysed in the paper, which concludes with an appeal for more objectivity in providing information on energy, such information being at present very ''polluted'' and exerting a major influence on the views of experts. (author)

Smart electric vehicle (EV) charging and grid integration apparatus and methods

Science.gov (United States)

Gadh, Rajit; Mal, Siddhartha; Prabhu, Shivanand; Chu, Chi-Cheng; Sheikh, Omar; Chung, Ching-Yen; He, Lei; Xiao, Bingjun; Shi, Yiyu

2015-05-05

An expert system manages a power grid wherein charging stations are connected to the power grid, with electric vehicles connected to the charging stations, whereby the expert system selectively backfills power from connected electric vehicles to the power grid through a grid tie inverter (if present) within the charging stations. In more traditional usage, the expert system allows for electric vehicle charging, coupled with user preferences as to charge time, charge cost, and charging station capabilities, without exceeding the power grid capacity at any point. A robust yet accurate state of charge (SOC) calculation method is also presented, whereby initially an open circuit voltage (OCV) based on sampled battery voltages and currents is calculated, and then the SOC is obtained based on a mapping between a previously measured reference OCV (ROCV) and SOC. The OCV-SOC calculation method accommodates likely any battery type with any current profile.

Dashboard: biogas for electricity production - Third quarter 2015

International Nuclear Information System (INIS)

Cavaud, Denis

2015-12-01

This publication describes the situation of biogas-based electricity production in France and its evolution over the first quarters of 2015. A map indicates the level of connected power per district. Graphs illustrate the evolution of the number of new connections per quarter since 2009, the evolution of electricity quarterly production since 2011. Tables indicate the number of installations per power level (less than 0.5 MW, between 0.5 and 1.0 MW, more than 1 MW) and per installation type. Regional data are given in terms of number of installations, installed power in September 2015 and in December 2015, regional share and evolution

Multiplex electric discharge gas laser system

Science.gov (United States)

Laudenslager, James B. (Inventor); Pacala, Thomas J. (Inventor)

1987-01-01

A multiple pulse electric discharge gas laser system is described in which a plurality of pulsed electric discharge gas lasers are supported in a common housing. Each laser is supplied with excitation pulses from a separate power supply. A controller, which may be a microprocessor, is connected to each power supply for controlling the application of excitation pulses to each laser so that the lasers can be fired simultaneously or in any desired sequence. The output light beams from the individual lasers may be combined or utilized independently, depending on the desired application. The individual lasers may include multiple pairs of discharge electrodes with a separate power supply connected across each electrode pair so that multiple light output beams can be generated from a single laser tube and combined or utilized separately.

Becoming Music-Making Music Teachers: Connecting Music Making, Identity, Wellbeing, and Teaching for Four Student Teachers

Science.gov (United States)

Pellegrino, Kristen

2015-01-01

The purpose of this descriptive case study was to examine the developing music teacher identity of four student music teachers by exploring the meanings of music making and the intersections of music making and teaching. Participants all had dual student teaching placements: elementary general music and secondary band. Data were generated through…

Future electrical distribution grids: Smart Grids

International Nuclear Information System (INIS)

Hadjsaid, N.; Sabonnadiere, J.C.; Angelier, J.P.

2010-01-01

The new energy paradigm faced by distribution network represents a real scientific challenge. Thus, national and EU objectives in terms of environment and energy efficiency with resulted regulatory incentives for renewable energies, the deployment of smart meters and the need to respond to changing needs including new uses related to electric and plug-in hybrid vehicles introduce more complexity and favour the evolution towards a smarter grid. The economic interest group in Grenoble IDEA in connection with the power laboratory G2ELab at Grenoble Institute of technology, EDF and Schneider Electric are conducting research on the electrical distribution of the future in presence of distributed generation for ten years.Thus, several innovations emerged in terms of flexibility and intelligence of the distribution network. One can notice the intelligence solutions for voltage control, the tools of network optimization, the self-healing techniques, the innovative strategies for connecting distributed and intermittent generation or load control possibilities for the distributor. All these innovations are firmly in the context of intelligent networks of tomorrow 'Smart Grids'. (authors)

Brain state-dependence of electrically evoked potentials monitored with head-mounted electronics.

Science.gov (United States)

Richardson, Andrew G; Fetz, Eberhard E

2012-11-01

Inferring changes in brain connectivity is critical to studies of learning-related plasticity and stimulus-induced conditioning of neural circuits. In addition, monitoring spontaneous fluctuations in connectivity can provide insight into information processing during different brain states. Here, we quantified state-dependent connectivity changes throughout the 24-h sleep-wake cycle in freely behaving monkeys. A novel, head-mounted electronic device was used to electrically stimulate at one site and record evoked potentials at other sites. Electrically evoked potentials (EEPs) revealed the connectivity pattern between several cortical sites and the basal forebrain. We quantified state-dependent changes in the EEPs. Cortico-cortical EEP amplitude increased during slow-wave sleep, compared to wakefulness, while basal-cortical EEP amplitude decreased. The results demonstrate the utility of using portable electronics to document state-dependent connectivity changes in freely behaving primates.

Making EDM Electrodes By Stereolithography

Science.gov (United States)

Barlas, Philip A.

1988-01-01

Stereolithography is computer-aided manufacturing technique. Used to make models and molds of electrodes for electrical-discharge machining (EDM). Eliminates intermediate steps in fabrication of plastic model of object used in making EDM electrode to manufacture object or mold for object.

Using fleets of electric-drive vehicles for grid support

International Nuclear Information System (INIS)

Tomic, Jasna; Kempton, Willett

2007-01-01

Electric-drive vehicles can provide power to the electric grid when they are parked (vehicle-to-grid power). We evaluated the economic potential of two utility-owned fleets of battery-electric vehicles to provide power for a specific electricity market, regulation, in four US regional regulation services markets. The two battery-electric fleet cases are: (a) 100 Th.nk City vehicle and (b) 252 Toyota RAV4. Important variables are: (a) the market value of regulation services, (b) the power capacity (kW) of the electrical connections and wiring, and (c) the energy capacity (kWh) of the vehicle's battery. With a few exceptions when the annual market value of regulation was low, we find that vehicle-to-grid power for regulation services is profitable across all four markets analyzed. Assuming now more than current Level 2 charging infrastructure (6.6 kW) the annual net profit for the Th.nk City fleet is from US$ 7000 to 70,000 providing regulation down only. For the RAV4 fleet the annual net profit ranges from US$ 24,000 to 260,000 providing regulation down and up. Vehicle-to-grid power could provide a significant revenue stream that would improve the economics of grid-connected electric-drive vehicles and further encourage their adoption. It would also improve the stability of the electrical grid. (author)

Connections in wood and foliage

Science.gov (United States)

Kevin T. Smith

2009-01-01

Trees are networked systems that capture energy, move massive amounts of water and material, and provide the setting for human society and for the lives of many associated organisms. Tree survival depends on making and breaking the right connections within these networks.

Voltage balancing strategies for serial connection of microbial fuel cells

Science.gov (United States)

Khaled, Firas; Ondel, Olivier; Allard, Bruno; Buret, François

2015-07-01

The microbial fuel cell (MFC) converts electrochemically organic matter into electricity by means of metabolisms of bacteria. The MFC power output is limited by low voltage and low current characteristics in the range of microwatts or milliwatts per litre. In order to produce a sufficient voltage level (>1.5 V) and sufficient power to supply real applications such as autonomous sensors, it is necessary to either scale-up one single unit or to connect multiple units together. Many topologies of connection are possible as the serial association to improve the output voltage, or the parallel connection to improve the output current or the series/parallel connection to step-up both voltage and current. The association of MFCs in series is a solution to increase the voltage to an acceptable value and to mutualize the unit's output power. The serial association of a large number of MFCs presents several issues. The first one is the hydraulic coupling among MFCs when they share the same substrate. The second one is the dispersion between generators that lead to a non-optimal stack efficiency because the maximum power point (MPP) operation of all MFCs is not permitted. Voltage balancing is a solution to compensate non-uniformities towards MPP. This paper presents solutions to improve the efficiency of a stack of serially connected MFCs through a voltage-balancing circuit. Contribution to the topical issue "Electrical Engineering Symposium (SGE 2014)", edited by Adel Razek

Analysis of electricity price in Danish competitive electricity market

DEFF Research Database (Denmark)

Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

2012-01-01

electricity markets in some ways, is chosen as the studied power system. 10 year actual data from the Danish competitive electricity market are collected and analyzed. The relationship among the electricity price (both the spot price and the regulation price), the consumption and the wind power generation...... in an electricity market is investigated in this paper. The spot price and the regulation price generally decrease when the wind power penetration in the power system increases or the consumption of the power system decreases. The statistical characteristics of the spot price and the regulation price for different...... consumption periods and wind power penetration are analyzed. Simulation results show that the findings of this paper are useful for wind power generation companies to make the optimal bidding strategy so that the imbalance cost of trading wind power on the electricity market could be reduced....

Concept of intellectual charging system for electrical and plug-in hybrid vehicles in Russian Federation

Science.gov (United States)

Kolbasov, A.; Karpukhin, K.; Terenchenko, A.; Kavalchuk, I.

2018-02-01

Electric vehicles have become the most common solution to improve sustainability of the transportation systems all around the world. Despite all benefits, wide adaptation of electric vehicles requires major changes in the infrastructure, including grid adaptation to the rapidly increased power demand and development of the Connected Car concept. This paper discusses the approaches to improve usability of electric vehicles, by creating suitable web-services, with possible connections vehicle-to-vehicle, vehicle-to-infrastructure, and vehicle-to-grid. Developed concept combines information about electrical loads on the grid in specific direction, navigation information from the on-board system, existing and empty charging slots and power availability. In addition, this paper presents the universal concept of the photovoltaic integrated charging stations, which are connected to the developed information systems. It helps to achieve rapid adaptation of the overall infrastructure to the needs of the electric vehicles users with minor changes in the existing grid and loads.

Thermoelectric System in Different Thermal and Electrical Configurations: Its Impact in the Figure of Merit

Directory of Open Access Journals (Sweden)

Alexander Vargas-Almeida

2013-05-01

Full Text Available In this work, we analyze different configurations of a thermoelectric system (TES composed of three thermoelectric generators (TEGs. We present the following considerations: (a TES thermally and electrically connected in series (SC; (b TES thermally and electrically connected in parallel (PSC; and (c parallel thermally and series electrical connection (SSC. We assume that the parameters of the TEGs are temperature-independent. The systems are characterized by three parameters, as it has been showed in recent investigations, namely, its internal electrical resistance, R, thermal conductance under open electrical circuit condition, K, and Seebeck coefficient α. We derive the equivalent parameters for each of the configurations considered here and calculate the Figure of Merit Z for the equivalent system. We show the impact of the configuration of the system on Z, and we suggest optimum configuration. In order to justify the effectiveness of the equivalent Figure of Merit, the corresponding efficiency has been calculated for each configuration.

Design and dimensioning of pressfit connections in control modules; Betriebsfeste Bemessung von Steckverbindern in Steuergeraeten

Energy Technology Data Exchange (ETDEWEB)

Kimpel, Thomas; Jauernig, Udo [Robert Bosch GmbH, Schwieberdingen (Germany). Geschaeftsbereich Automotive Electronics; Becker, Rolf [Robert Bosch GmbH, Reutlingen (Germany); Wagener, Rainer [Fraunhofer-Institut fuer Betriebsfestigkeit und Systemzuverlaessigkeit (LBF), Darmstadt (Germany). Gruppe Bauteilgebundenes Werkstoffverhalten; Kaufmann, Heinz; Sonsino, Cetin Morris [Fraunhofer-Institut fuer Betriebsfestigkeit und Systemzuverlaessigkeit (LBF), Darmstadt (Germany)

2013-07-01

Pressfit technology as a cold contacting technology connects the printed circuit board to the external connection of the control module. The main function of the pressfit connection is the transportation of electrical signals and power. Depending on the construction the fixation of the printed circuit board can occur as a further function. The reliability requirements indicate that these functions are preserved over life time. A design model of the pressfit connection was developed for measuring the functions during cyclic mechanical loads. Furthermore, a suitable test bench was designed for applying the mechanical loads from production and operation. The failure mechanisms and resulting failures which occur under cyclic mechanical loads were acquired with the design model. The focal point was the contact zone because it is as the joint between the pressfit and the plated through hole a possible weak spot. It was shown that the electrical resistance of the contact zone could lead to a functional failure of the pressfit connection because of fretting corrosion in the gross slip mode. A correlation between the mechanical load capacity of the contact zone and the electrical resistance was established. For this, the multi physical functions of the joint were used with the objective to avoid fretting corrosion in gross slip mode during lifetime. A suitable test method to detect the load capacity in three dimensions was developed. (orig.)

Feasibility study of Thermal Electric Generator Configurations as Renewable Energy Sources

Science.gov (United States)

Akmal Johar, Muhammad; Yahaya, Zulkarnain; Faizan Marwah, Omar Mohd; Jamaludin, Wan Akashah Wan; Najib Ribuan, Mohamed

2017-10-01

Thermoelectric Generator is a solid state device that able to convert thermal energy into electrical energy via temperature differences. The technology is based on Seebeck effect that was discovered in year 1821, however till now there is no real application to exploit this capability in mass scale. This research will report the performance analysis of TEG module in controlled environment of lab scale model. National Instrument equipment and Labview software has been choosen and developed to measure the TEG module in various configurations. Based on the experiment result, an additional passive cooling effort has produced a better ΔT by 7°C. The optimal electrical loading of single TEG is recorded at 200Ω. As for circuit connections, series connection has shown superior power output when compared to parallel connection or single TEG. A series connection of two TEGs has produced power output of 416.82μW when compared to other type connections that only produced around 100μW.

Plug-in hybrid electric vehicles in dynamical energy markets

NARCIS (Netherlands)

Kessels, J.T.B.A.; Bosch, P.P.J. van den

2008-01-01

The plug-in hybrid electric vehicle allows vehicle propulsion from multiple internal power sources. Electric energy from the grid can be utilized by means of the plug-in connection. An on-line energy management (EM) strategy is proposed to minimize the costs for taking energy from each power source.

Power Enhancement of Partial Shaded PV Array by Optimizing the Electrical Connection of Module

Directory of Open Access Journals (Sweden)

Wang Mengyao

2015-01-01

Full Text Available The maximum output power (Pmax generated from photovoltaic (PV array will be apparently reduced if the array is partially shaded. In order to enhance Pmax generated from partial shaded PV array, several interconnection schemes of array are proposed. Among these schemes, the totally cross tied (TCT scheme and the recently proposed static scheme are widely discussed. It was reported that Pmax produced with static scheme is equal to the TCT scheme even under worst conditions. However, in these simulations the illumination of every single module is assumed to be uniform, but in urban environments the illumination of modules on the edge of shadow is more likely to be non-uniform. In this paper, first, a comprehensive circuit-level simulation, which is implemented in PSpice, has been done to investigate performance of PV array with both TCT scheme and static scheme under different partial shading conditions. And the results show that Pmax generated from static scheme is higher than that form TCT scheme if the illumination of every single module is uniform, however if some modules are partially shaded, the Pmax with static scheme is more likely less than that with TCT scheme. Then, the electrical connection of a module is improved for the purpose of enhancing Pmax under partial shading conditions in which some modules in the array are partially shaded. And the simulation results show that Pmax is apparently increased by employing the improved modules.

Solar-coupled electric vehicles

International Nuclear Information System (INIS)

Willer, B.

1993-01-01

An electrical drive is an alternative to the present internal combustion engines. The electric car produces no exhaust gas where it is used and drives practically noiselessly. The energy required for driving is usually taken from an electro-chemical battery. The necessary electricity generation generates emission and CO 2 , depending on the primary energy used. An alternative is provided by electricity generation with the aid of regenerative energy. Apart from hydroelectric and wind energy, solar energy can make a considerable contribution in the future. (orig.) [de

Enhanced Efficiency of Thermoelectric Generator by Optimizing Mechanical and Electrical Structures

Directory of Open Access Journals (Sweden)

Jinlong Chen

2017-09-01

Full Text Available Much attention has been paid to the application of low temperature thermal resources, especially for power generation in recent years. Most of the current commercialized thermal (including geothermal power-generation technologies convert thermal energy to electric energy indirectly, that is, making mechanical work before producing electricity. Technology using a thermoelectric generator (TEG, however, can directly transform thermal energy into electricity through the Seebeck effect. TEG technology has many advantages such as compactness, quietness, and reliability because there are no moving parts. One of the biggest disadvantages of TEGs is the low efficiency from thermal to electric energy. For this reason, we redesigned and modified our previous 1 KW (at a temperature difference of around 120 °C TEG system. The output power of the system was improved significantly, about 34.6% greater; the instantaneous efficiency of the TEG system could reach about 6.5%. Laboratory experiments have been conducted to measure the output power at different conditions: different connection modes between TEG modules, different mechanical structures, and different temperature differences between hot and cold sides. The TEG apparatus has been tested and the data have been presented. This kind of TEG power system can be applied in many thermal and geothermal sites with low temperature resources, including oil fields where fossil and geothermal energies are coproduced.

Methods for the Optimal Design of Grid-Connected PV Inverters

DEFF Research Database (Denmark)

Koutroulis, Eftichios; Blaabjerg, Frede

2011-01-01

and the efficient processing of this power by the DC/AC inverter. In this paper two new methods are presented for the optimal design of a PV inverter power section, output filter and MPPT control strategy. The influences of the electric grid regulations and standards as well as the PV array operational......The DC/AC inverters are used in grid-connected PV energy production systems as the power processing interface between the PV energy source and the electric grid. The energy injected into the electric grid by the PV installation depends on the amount of power extracted from the PV power source...

Indicators of Malicious SSL Connections

NARCIS (Netherlands)

Bortolameotti, Riccardo; Peter, Andreas; Everts, Maarten Hinderik; Bolzoni, D.

2015-01-01

Internet applications use SSL to provide data confidential- ity to communicating entities. The use of encryption in SSL makes it impossible to distinguish between benign and malicious connections as the content cannot be inspected. Therefore, we propose and evaluate a set of indicators for malicious

Indicators of malicious SSL connections

NARCIS (Netherlands)

Bortolameotti, R.; Peter, A.; Everts, M.H.; Bolzoni, D.

2015-01-01

Internet applications use SSL to provide data confidentiality to communicating entities. The use of encryption in SSL makes it impossible to distinguish between benign and malicious connections as the content cannot be inspected. Therefore, we propose and evaluate a set of indicators for malicious

Emotional Intelligence and Decision Making

Directory of Open Access Journals (Sweden)

A M Kustubayeva

2011-12-01

Full Text Available The results of the experimental research of the connection between the efficiency of decision making and emotional intelligence are presented in the article. The empirical data indicate that the ability to regulate emotion is an important indicator of the efficiency of decision making in the conditions of psychological experiment.

Fundamentals of Grid Connected Photo-Voltaic Power Electronic Converter Design

OpenAIRE

Evju, Svein Erik

2007-01-01

In this master thesis the basic theory of grid connected photo-voltaic systems is explained, giving an introduction to the different aspects of system design. Starting with a look at the standards concerning grid connection of distributed resources, and working its way through how the photo-voltaic cells work, to how photo-voltaic modules with electrical converters can be arranged. Some different converter topologies suitable for use with photo-voltaics are found, and based on these topologie...

Make Sense?

DEFF Research Database (Denmark)

Gyrd-Jones, Richard; Törmälä, Minna

Purpose: An important part of how we sense a brand is how we make sense of a brand. Sense-making is naturally strongly connected to how we cognize about the brand. But sense-making is concerned with multiple forms of knowledge that arise from our interpretation of the brand-related stimuli......: Declarative, episodic, procedural and sensory. Knowledge is given meaning through mental association (Keller, 1993) and / or symbolic interaction (Blumer, 1969). These meanings are centrally related to individuals’ sense of identity or “identity needs” (Wallpach & Woodside, 2009). The way individuals make...... sense of brands is related to who people think they are in their context and this shapes what they enact and how they interpret the brand (Currie & Brown, 2003; Weick, Sutcliffe, & Obstfeld, 2005; Weick, 1993). Our subject of interest in this paper is how stakeholders interpret and ascribe meaning...

Croatia's rural areas - renewable energy based electricity generation for isolated grids

Directory of Open Access Journals (Sweden)

Protic Sonja Maria

2014-01-01

Full Text Available Several Western Balkan states face the consequences of the Yugoslavian war, which left hometowns with dilapidated electricity grid connections, a high average age of power plant capacities and low integration of renewable energy sources, grid bottlenecks and a lack of competition. In order to supply all households with electricity, UNDP Croatia did a research on decentralized supply systems based on renewable energy sources. Decentralized supply systems offer cheaper electricity connections and provide faster support to rural development. This paper proposes a developed methodology to financially compare isolated grid solutions that primarily use renewable energies to an extension of the public electricity network to small regions in Croatia. Isolated grid supply proves to be very often a preferable option. Furthermore, it points out the lack of a reliable evaluation of non-monetizable aspects and promotes a new interdisciplinary approach.

Study on Earthquake Response of High Voltage Electrical Equipment Coupling System with Flexible Busbar

Science.gov (United States)

Liu, Chuncheng; Qu, Da; Wang, Chongyang; Lv, Chunlei; Li, Guoqiang

2017-12-01

With the rapid development of technology and society, all walks of life in China are becoming more and more dependent on power systems. When earthquake occurs, the electrical equipment of substation is prone to damage because of its own structural features, top-heavy, and brittleness of main body. At the same time, due to the complex coupling of the soft electrical connection of substation electrical equipment, the negative impact can not be estimated. In this paper, the finite element model of the coupling system of the single unit of high voltage electrical equipment with the connecting soft bus is established and the seismic response is analysed. The results showed that there is a significant difference between the simple analysis for the seismic response of electrical equipment monomer and the analytical results of electrical equipment systems, and the impact on different electrical equipment is different. It lays a foundation for the future development of seismic performance analysis of extra high voltage electrical equipment.

Research on Relation between El Nino Climate and Summer Electricity Consumption

Science.gov (United States)

Miao, B.; Lin, J. Y.; Liu, C.

2018-01-01

El Nino is a typical climate phenomena. Such phenomena would have influence on climate in China and furthermore impact the electricity condition. This paper is purposed to explore how El Nino phenomena affecting electricity and make prediction on summer electricity consumption. Since meteorological characteristics are complex and multiplex, a variety of meteorological factors should be considered and the paper used Body Feeling Temperature to measure it. Furthermore, to make prediction on summer electricity, the paper used the Pearson Analysis to measure the correlation between weather and electricity and then extracted the weather-used electricity from the whole society electricity using least square method. Finally, the paper built the model on relation between weather-used electricity and body feeling temperature, and took Beijing as an example to make electricity prediction. The prediction idea and model the paper put forward is reliable and practicable.

Applicability of the lattice Boltzmann method to determine the ohmic resistance in equivalent resistor connections

Science.gov (United States)

Espinoza-Andaluz, Mayken; Barzola, Julio; Guarochico-Moreira, Víctor H.; Andersson, Martin

2017-12-01

Knowing the ohmic resistance in the materials allow to know in advance its electrical behavior when a potential difference is applied, and therefore the prediction of the electrical performance can be achieved in a most certain manner. Although the Lattice Boltzmann method (LBM) has been applied to solve several physical phenomena in complex geometries, it has only been used to describe the fluid phase, but applicability studies of LBM on the solid-electric-conducting material have not been carried out yet. The purpose of this paper is to demonstrate the accuracy of calculating the equivalent resistor connections using LBM. Several series and parallel resistor connections are effected. All the computations are carried out with 3D models, and the domain materials are designed by the authors.

Connections between radiation and positronium chemistry

International Nuclear Information System (INIS)

Hirade, Tetsuya

2007-01-01

Some of the important connections between radiation chemistry and positronium chemistry started from the establishment of the spur reaction model proposed by Mogensen. Now, the modified model, the blob model proposed by Stepanov and Byakov, is making it possible to have the quantitative or semi-quantitative view of the positronium formation by using the distributions of positrons and excess electrons. Some of the interesting topics will be picked up here to understand the connections between radiation chemistry and positronium chemistry

Wireless power transfer for electric vehicle

OpenAIRE

Mude, Kishore Naik

2015-01-01

Wireless Power Transfer (WPT) systems transfer electric energy from a source to a load without any wired connection. WPTs are attractive for many industrial applications because of their advantages compared to the wired counterpart, such as no exposed wires, ease of charging, and fearless transmission of power in adverse environmental conditions. Adoption of WPTs to charge the on-board batteries of an electric vehicle (EV) has got attention from some companies, and efforts are being made for ...

Study of time dependence and spectral composition of the signal in circuit of ac electric point motors

Directory of Open Access Journals (Sweden)

S. Yu. Buryak

2014-12-01

Full Text Available Purpose. The paper is aimed to establish the dependence of changes in the time domain and spectral components of the current in the circuit of the AC electric point motor on its technical condition, to identify the common features for the same type of damage. It is necessary using the analysis of the received signals to carry out the remote diagnosis and determination of faults and defects of electric point motors. In addition it suggested to accelerate the process of the failure, malfunction and damage search. Authors propose the automated approach to the service of remote floor automation equipment, which is located in the envelope of trains. Reduction of the threat to life and health of staff by reducing the residence time in the zone of train movement. Reduce the impact of human factors on the result of service. Methodology. The paper studies the structure, parameters and characteristics, the operation and maintenance characteristics of the AC electric point motors. Determination of the main types of possible faults in the process depending on the operating conditions. Presentation of the electric motor as an object of diagnosis. Findings. The time dependences of the current in the circuit of electric point motor for its various states was obtained. The connection between the technical condition of electric point motor and the performance of current curve in time and spectral domains was established. The revealed deviations from the reference signal were justified. According to the obtained results it was made the conclusion. Originality. A method for diagnosing the state of the AC electric point motor by the time dependence and the spectral composition of the current in its circuit was proposed. The connection diagram to the motor windings based on non-infringement of electric parameters of connection circuit in the actual operating conditions was applied. Practical value. The obtained results suggest the possibility and feasibility of

Operation of high-current connections for the electric supply of conurbations

Energy Technology Data Exchange (ETDEWEB)

Ambrosch, H; Krause, D

1975-01-01

The suitability of superconducting cables for the electric power supply of a large town is investigated on the basis of technical and economic parameters and from the point of view of the power supply.

Integrated Electricity Planning Comprise Renewable Energy and Feed-In Tariff

OpenAIRE

Ho Wai Shin; Haslenda Hashim

2012-01-01

Problem statement: Mitigation of global warming and energy crisis has called upon the need of an efficient tool for electricity planning. This study thus presents an electricity planning tool that incorporates RE with Feed in-Tariff (FiT) for various sources of Renewable Energy (RE) to minimize grid-connected electricity generation cost as well as to satisfy nominal electricity demand and CO2 emission reduction target. Approach: In order to perform these tasks, a general Mixed Integer Linear ...

Analysis of the influences of grid-connected PV power system on distribution grids

Directory of Open Access Journals (Sweden)

Dumitru Popandron

2013-12-01

Full Text Available This paper presents the analysis of producing an electric power of 2.8 MW using a solar photovoltaic plant. The PV will be grid connected to the distribution network. The study is focused on the influences of connecting to the grid of a photovoltaic system, using modern software for analysis, modeling and simulation in power systems.

A Model of Trusted Connection Architecture

Directory of Open Access Journals (Sweden)

Zhang Xun

2017-01-01

Full Text Available According to that traditional trusted network connection architecture (TNC has limitations on dynamic network environment and the user behavior support, we develop TCA to propose a trusted connection architecture supporting behavior measurement (TCA-SBM, besides, the structure diagram of network architecture is given. Through introducing user behavior measure elements, TCA-SBM can conduct measurement on the whole network in time dimension periodically, and refine the measurement on network behavior in measure dimension to conduct fine-grained dynamic trusted measurement. As a result, TCA-SBM enhances the TCA’s ability to adapt to the dynamic change of network and makes up the deficiency of trusted computing framework in the network connection.

1-MWp electrical photovoltaic plant (EPHOP - project)

International Nuclear Information System (INIS)

Vitanov, P.; Toneva, A.; Petkanchin, L.; Ivancheva, J.; Neshev, S.

2000-01-01

The presented project concerns the realization of a grid connected 1-MW p pilot photovoltaic plant on the territory of Bulgaria.The purpose of the project is to demonstrate and prove solar energy advantages. A special attention will be paid to the possibility the generated electricity to join the national electric network. The site selection according to the meteorological conditions as well as general aspects of the project are discussed

The EU Electricity Policy. Outlook for the Smart Grid Roll-Out

International Nuclear Information System (INIS)

Faure-Schuyer, Aurelie

2014-01-01

The energy transition from a socio-economic system based on fossil fuels to a sustainable low-carbon system is a multi-faceted process. This 'transformation' of the energy system, more specifically of the power system, creates several challenges. These concern in particular the connections with the existing electricity infrastructure of new renewable power sources and the distribution of generating systems, together with automated grid assets and smart meters. The European energy transition is based on two different revolutions: i) the 'post-World War II' industrial investment recovery, when electricity systems were built; and ii) the 'Information Technology' revolution that is bringing new communication and connection modes to the grid. There is no unique path towards a de-carbonised electricity system. The implementation of this development depends on the current local configuration of electricity grids, the interaction between grid operators, the generation mix, the availability of backup generation capacities and the level of cross-border interconnections. Moreover, this evolution impacts the roles of all actors of the energy system, in particular those of Transmission System Operators (TSOs), of Distribution System operators (DSOs) and of National Regulatory Authorities (NRAs). Besides the technical challenge, the Energy transition requires the transformation of business models designed as platforms, which are able to integrate different levels of stakeholders, whereas in the past, utilities were based on vertical, public monopoly structures that were often paid based on cost-of-service rules. The traditional utility models were characterised by centralised governance but as a result of technological changes, this system is making way for a more horizontal and multilateral governance. The role of consumers is also changing, with new attributes in particular with regards to demand-response measures. The purpose of this paper is to analyse the key structural

46 CFR 113.35-7 - Electric engine order telegraph systems; operations.

Science.gov (United States)

2010-10-01

... transmitter handle automatically connects that transmitter electrically to the engineroom indicator and simultaneously disconnects electrically all other transmitters. The reply pointers of all transmitters must... manually operated transfer switch which will disconnect the system in the unattended navigating bridge must...

Making Connections to Students' Lives and Careers Throughout a General Education Science Course

Science.gov (United States)

LaDue, D. S.

2014-12-01

The University of Oklahoma's general education lecture course Severe & Unusual Weather, taught in two sections each fall and spring, covers about nine topics. The sections are taught by different instructors, each of whom has flexibility to employ a variety of instructional strategies and choose specific topics to cover while meeting the requirement that general education courses in the natural sciences help students understand the importance of the science for appreciating the world around them. Students enrolled have been approximately 6-10% returning adult students, some of whom were veterans or active duty military, and about 10% members of racial or ethnic groups. Their majors are mostly in the humanities (theater, photography) and social sciences (education, English, journalism, sociology), with some natural science majors (psychology, aviation). For the past two years, Section 001 has been designed with adult and active learning concepts in mind, using deliberate connections between course content and students' lives and careers to motivate meaningful learning. Students were grouped in teams according to similar majors and assigned group presentations connecting course content to topics that should interest them, such as economic impacts of weather, societal and personal impacts of severe weather, risks to aviation, media coverage of weather, and psychological and sociological responses to weather risks. Students learn about the peer review process for scientific papers while also exploring a connection of course content to their future career or life interests through papers that are run through a mock peer review process. Public policy is discussed in several sections of the course, such as hurricane building codes, wind-resistant construction in tornado alley, and the disproportionate impacts of weather and climate on certain socioeconomic groups. Most students deeply appreciate the opportunity to explore how course content intersects with their lives

Electrode Cooling Effect on Out-Of-Phase Electrothermal Streaming in Rotating Electric Fields

Directory of Open Access Journals (Sweden)

Weiyu Liu

2017-11-01

Full Text Available In this work, we focus on investigating electrothermal flow in rotating electric fields (ROT-ETF, with primary attention paid to the horizontal traveling-wave electrothermal (TWET vortex induced at the center of the electric field. The frequency-dependent flow profiles in the microdevice are analyzed using different heat transfer models. Accordingly, we address in particular the importance of electrode cooling in ROT-ETF as metal electrodes of high thermal conductivity, while substrate material of low heat dissipation capability is employed to develop such microfluidic chips. Under this circumstance, cooling of electrode array due to external natural convection on millimeter-scale electrode pads for external wire connection occurs and makes the internal temperature maxima shift from the electrode plane to a bit of distance right above the cross-shaped interelectrode gaps, giving rise to reversal of flow rotation from a typical repulsion-type to attraction-type induction vortex, which is in good accordance with our experimental observations of co-field TWET streaming at frequencies in the order of reciprocal charge relaxation time of the bulk fluid. These results point out a way to make a correct interpretation of out-of-phase electrothermal streaming behavior, which holds great potential for handing high-conductivity analytes in modern microfluidic systems.

Continuously Connected With Mobile IP

Science.gov (United States)

2002-01-01

Cisco Systems developed Cisco Mobile Networks, making IP devices mobile. With this innovation, a Cisco router and its connected IP devices can roam across network boundaries and connection types. Because a mobile user is able to keep the same IP address while roaming, a live IP connection can be maintained without interruption. Glenn Research Center jointly tested the technology with Cisco, and is working to use it on low-earth-orbiting research craft. With Cisco's Mobile Networks functionality now available in Cisco IOS Software release 12.2(4)T, the commercial advantages and benefits are numerous. The technology can be applied to public safety, military/homeland security, emergency management services, railroad and shipping systems, and the automotive industry. It will allow ambulances, police, firemen, and the U.S. Coast Guard to stay connected to their networks while on the move. In the wireless battlefield, the technology will provide rapid infrastructure deployment for U.S. national defense. Airline, train, and cruise passengers utilizing Cisco Mobile Networks can fly all around the world with a continuous Internet connection. Cisco IOS(R) Software is a registered trademark of Cisco Systems.

Structural and effective connectivity in focal epilepsy

Directory of Open Access Journals (Sweden)

Christopher S. Parker

2018-01-01

Full Text Available Patients with medically-refractory focal epilepsy may be candidates for neurosurgery and some may require placement of intracranial EEG electrodes to localise seizure onset. Assessing cerebral responses to single pulse electrical stimulation (SPES may give diagnostically useful data. SPES produces cortico-cortical evoked potentials (CCEPs, which infer effective brain connectivity. Diffusion-weighted images and tractography may be used to estimate structural brain connectivity. This combination provides the opportunity to observe seizure onset and its propagation throughout the brain, spreading contiguously along the cortex explored with electrodes, or non-contiguously. We analysed CCEPs and diffusion tractography in seven focal epilepsy patients and reconstructed the effective and structural brain networks. We aimed to assess the inter-modal similarity of the networks at a large scale across the cortex, the effective and structural connectivity of the ictal-onset zone, and investigate potential mechanisms of non-contiguous seizure spread. We found a significant overlap between structural and effective networks. Effective network CCEP amplitude, baseline variation, and outward connectivity was higher at ictal-onset zones, while structural connection strength within the ictal-onset zone tended to be higher. These findings support the concept of hyperexcitable cortex being associated with seizure generation. The high prevalence of structural and effective connections from the ictal-onset zone to sites of non-contiguous spread suggests that macroscopic structural and effective connections are plausible routes for non-contiguous seizure spread.

Design and simulation of a novel E-mode GaN MIS-HEMT based on a cascode connection for suppression of electric field under gate and improvement of reliability

Science.gov (United States)

Li, Weiyi; Zhang, Zhili; Fu, Kai; Yu, Guohao; Zhang, Xiaodong; Sun, Shichuang; Song, Liang; Hao, Ronghui; Fan, Yaming; Cai, Yong; Zhang, Baoshun

2017-07-01

We proposed a novel AlGaN/GaN enhancement-mode (E-mode) high electron mobility transistor (HEMT) with a dual-gate structure and carried out the detailed numerical simulation of device operation using Silvaco Atlas. The dual-gate device is based on a cascode connection of an E-mode and a D-mode gate. The simulation results show that electric field under the gate is decreased by more than 70% compared to that of the conventional E-mode MIS-HEMTs (from 2.83 MV/cm decreased to 0.83 MV/cm). Thus, with the discussion of ionized trap density, the proposed dual-gate structure can highly improve electric field-related reliability, such as, threshold voltage stability. In addition, compared with HEMT with field plate structure, the proposed structure exhibits a simplified fabrication process and a more effective suppression of high electric field. Project supported by the Key Technologies Support Program of Jiangsu Province (No. BE2013002-2) and the National Key Scientific Instrument and Equipment Development Projects of China (No. 2013YQ470767).

Perceptual decision-making difficulty modulates feedforward effective connectivity to the dorsolateral prefrontal cortex

Directory of Open Access Journals (Sweden)

Bidhan eLamichhane

2015-09-01

Full Text Available Diverse cortical structures are known to coordinate activity as a network in relaying and processing of visual information to discriminate visual objects. However, how this discrimination is achieved is still largely unknown. To contribute to answering this question, we used face-house categorization tasks with three levels of noise in face and house images in functional magnetic resonance imaging (fMRI experiments involving thirty-three participants. The behavioral performance error and response time (RT were correlated with noise in face-house images. We then built dynamical causal models (DCM of fMRI blood-oxygenation level dependent (BOLD signals from the face and house category-specific regions in ventral temporal cortex, the fusiform face area (FFA and parahippocampal place area (PPA, and the dorsolateral prefrontal cortex (dlPFC. We found a strong feed-forward intrinsic connectivity pattern from FFA and PPA to dlPFC. Importantly, the feed-forward connectivity to dlPFC was significantly modulated by the perception of both faces and houses. The dlPFC-BOLD activity, the connectivity from FFA and PPA to the dlPFC all increased with noise level. These results suggest that the FFA-PPA-dlPFC network plays an important role for relaying and integrating competing sensory information to arrive at perceptual decisions.

The electrical system of nuclear power plant

International Nuclear Information System (INIS)

Firman Silitonga; Gunarwan Prayitno

2009-01-01

In these system, electrical power system is supplied from two-offsite transmission system respective main transformer and house service transformer; and reserve transformer. The electrical load in these system consist of safety electrical system and non-safety electrical system, The safety electrical and non safety electrical systems consist of four 6,9 kV AC medium voltage bus and 480 V AC low voltage bus system. The DC power system consist of four safety 125 V DC power system and the two non-safety 125 DC power systems. The equipment in these electrical system is main turbine-generator; GTG safety; GTG alternate; uninterrupted power supply (UPS) and battery system. To protect electrical equipment and building to direct stroke and non direct stroke disturbances is installed netral grounding system and lightning protection and protection the personnel to touch-voltage is installed equipment grounding system and station grounding. The lightning arrester system is connected to station station grounding system. (author)

Low-CO(2) electricity and hydrogen: a help or hindrance for electric and hydrogen vehicles?

Science.gov (United States)

Wallington, T J; Grahn, M; Anderson, J E; Mueller, S A; Williander, M I; Lindgren, K

2010-04-01

The title question was addressed using an energy model that accounts for projected global energy use in all sectors (transportation, heat, and power) of the global economy. Global CO(2) emissions were constrained to achieve stabilization at 400-550 ppm by 2100 at the lowest total system cost (equivalent to perfect CO(2) cap-and-trade regime). For future scenarios where vehicle technology costs were sufficiently competitive to advantage either hydrogen or electric vehicles, increased availability of low-cost, low-CO(2) electricity/hydrogen delayed (but did not prevent) the use of electric/hydrogen-powered vehicles in the model. This occurs when low-CO(2) electricity/hydrogen provides more cost-effective CO(2) mitigation opportunities in the heat and power energy sectors than in transportation. Connections between the sectors leading to this counterintuitive result need consideration in policy and technology planning.

Estimator's electrical man-hour manual

CERN Document Server

Page, John S

1999-01-01

This manual's latest edition continues to be the best source available for making accurate, reliable man-hour estimates for electrical installation. This new edition is revised and expanded to include installation of electrical instrumentation, which is used in monitoring various process systems.

Saving electricity in a hurry. Dealing with temporary shortfalls in electricity supplies

Energy Technology Data Exchange (ETDEWEB)

none

2005-07-01

Blackouts are normally the result of imbalances in electricity supply and demand. A brief blackout is mostly an inconvenience. But persistent shortfalls ? those lasting days, weeks, or months ? can cause economic disruption and danger to human life in our technology-rich societies. Saving Electricity in a Hurry describes some of the recent power shortfalls, from Norway to New Zealand, from Tokyo to Arizona and the policies these regions used to quickly reduce their power consumption. How did the whole country of Sweden cut its power consumption by 4% in only three days? How did California save 14% in only a few months? While the temporary shortfalls in electricity supplies described in this book are relatively rare events, they disproportionately shape future energy policies. Saving Electricity in a Hurry shows that countries can quickly reduce electricity consumption without harming the economy as much as blackouts or unplanned curtailments. The strategies are diverse, unique and often surprisingly cheap. They include mass media campaigns ? where a good joke can save a Megawatt ? improvements in equipment efficiency and quickly adjusting electricity prices. This book explains how California replaced a million traffic signals with energy-saving models, how millions of Tokyo residents raised their thermostat settings, and how New Zealanders took shorter showers, all quickly enough to help avoid imminent blackouts. Finally, it connects these policies to the traditional goal of ?saving electricity slowly?.

Impact of plug-in electric vehicles on voltage unbalance in ...

African Journals Online (AJOL)

Plug-in electric vehicle (PEV) will soon be connected to residential distribution networks. ... generation units which transfer the energy stored in their battery into grid. ... electric vehicles on voltage imbalance in distribution system is presented. ... and other types of distribution generator such as solar photovoltaic and wind ...

The impact of high PV penetration levels on electrical distribution networks

Energy Technology Data Exchange (ETDEWEB)

Collinson, A; Beddoes, A; Thornycroft, J [Halcrow (United Kingdom); Strbac, G; Jenkins, N [UMIST, Manchester (United Kingdom); Verhoeven, B [KEMA (Netherlands)

2002-07-01

This report describes the results of a collaborative study by EA Technology, UMIST and Halcrow into the effects of large-scale connection of dispersed photovoltaic (PV) power systems on the national electricity supply network. The report is intended to help manufacturers and installers of PV systems and electricity companies to understand the issues associated with grid connection of PV power systems. The increased use of PV systems is expected to have a significant impact on the design, operation and management of electricity supply networks. The study examined three main areas: probability and risk analysis of islanding; PV and network voltage control (including analysis of voltage control in a commercial, domestic retrofit and domestic new build scenarios); and future low voltage network design and operational policies.

Regional Analysis of Aids and Prices for Small-scale Grid-connected Solar Photovoltaic Systems in Spain

International Nuclear Information System (INIS)

Varela, M.; Ramirez, L.; Mora, L.; Sidrach de Cardona, M.

2002-01-01

Electricity production from small solar photovoltaic systems in Spain obtains a premium pnce of 0,36 ε/kWh over the electricity market price or a fix price of 0,40 ε/kWh. The development of these small systems in Spain clearly demonstrates that the established prime is not sufficient in the majority of locations. On the other hand, the prime revision set up by the RD 2818/98, considering the profitability of the renewable installations, demand a regional analysis of small PV systems profitability necessary in Spain. The accomplished results permit to conclude that the amount of the current prime is by itself insufficient to make profitable the small grid-connected PV systems in anywhere of the national geography. To guarantee the profitability of these systems it should be necessary to place the fix price at around 0,93 ε/kWh. However, if the duplication of the current price obtained by these installations was considered, this could ensure the profitability of these small systems in at least the 77% of the land. (Author) 12 refs

Making connections

DEFF Research Database (Denmark)

Hilton, Annette

will be in the form of a presentation to outline for teachers the different applications of proportional reasoning across science subjects in upper primary and lower secondary schools. It will use examples from the Danish science curriculum to show teachers where and how proportional reasoning applies...

Development of an Android OS Based Controller of a Double Motor Propulsion System for Connected Electric Vehicles and Communication Delays Analysis

Directory of Open Access Journals (Sweden)

Pedro Daniel Urbina Coronado

2015-01-01

Full Text Available Developments of technologies that facilitate vehicle connectivity represent a market demand. In particular, mobile device (MD technology provides advanced user interface, customization, and upgradability characteristics that can facilitate connectivity and possibly aid in the goal of autonomous driving. This work explores the use of a MD in the control system of a conceptual electric vehicle (EV. While the use of MD for real-time control and monitoring has been reported, proper consideration has not been given to delays in data flow and their effects on system performance. The motor of a novel propulsion system for an EV was conditioned to be controlled in a wireless local area network by an ecosystem that includes a MD and an electronic board. An intended accelerator signal is predefined and sent to the motor and rotational speed values produced in the motor are sent back to the MD. Sample periods in which the communication really occurs are registered. Delays in the sample periods and produced errors in the accelerator and rotational speed signals are presented and analyzed. Maximum delays found in communications were of 0.2 s, while the maximum error produced in the accelerator signal was of 3.54%. Delays are also simulated, with a response that is similar to the behavior observed in the experiments.

Electric vehicles, magnetic levitation and superconductive levitation in Japan

International Nuclear Information System (INIS)

Wyczalek, F.A.

1988-01-01

This is a technological assessment of electric automotive vehicles, high speed magnetic levitation trains and hyperspeed superconductive magnetic levitation trains in Japan. It includes conventional battery electric vehicles for the automotive application, conventional magnetic levitation trains with peak speeds of 300 km/h and superconductive levitation trains capable of speeds over 500 km/h in transcontinental service. These electric vehicles have been under development since 1971 and are now considered ready for introduction into intercity commercial service. Conventional magnetic levitation trains are targeted to connect New Chitose International Airport with Sapporo and shorter connections in LasVegas, Philadelphia and Miami. The first superconductive train is planned for the Osaka to Tokyo link by the year 2000, a distance of 515 km. The initial step has been taken with approval of funding for the first five year phase of construction beginning with the Kansai project near Osaka

A multi-agent system for distribution grid congestion management with electric vehicles

DEFF Research Database (Denmark)

Hu, Junjie; Saleem, Arshad; You, Shi

2015-01-01

Electric vehicles (EVs) are widely regarded as valuable assets in the smart grid as distributed energy resources in addition to their primary transportation function. However, connecting EVs to the distribution network and recharging the EV batteries without any control may overload the transform......Electric vehicles (EVs) are widely regarded as valuable assets in the smart grid as distributed energy resources in addition to their primary transportation function. However, connecting EVs to the distribution network and recharging the EV batteries without any control may overload...

Electrical energy in France in 2009

International Nuclear Information System (INIS)

2009-12-01

The figures presented on this document account for the electricity flows recorded in Metropolitan France, including Corsica. Contents: national consumption; physical exchanges with foreign countries; electrical energy balance in France in 2009; net generation; noteworthy data for the year 2009 (daily maximum values of national consumption, thermal generation, hydro-electric generation, wind generation and balance of physical exchanges); electricity market: cross-borders contractual exchanges, balance responsible entities (Energy amount exchanged between balance responsible entities through the block exchange notifications), balancing mechanism (global amount of energy activated upwards and downwards), daily market coupling; power facilities: generating facilities in France (Nuclear, Fossil fuel thermal, Hydro-electric, Wind and Other renewable energy sources), transmission lines owned by RTE (circuit length in operation), transmission - transformers owned by RTE (installed capacity in operation); main transmission facilities commissioned during the year 2009 (substations connected to the RTE network and new or refurbished circuits)

Connectivity-based parcellation of the human orbitofrontal cortex.

Science.gov (United States)

Kahnt, Thorsten; Chang, Luke J; Park, Soyoung Q; Heinzle, Jakob; Haynes, John-Dylan

2012-05-02

The primate orbitofrontal cortex (OFC) is involved in reward processing, learning, and decision making. Research in monkeys has shown that this region is densely connected with higher sensory, limbic, and subcortical regions. Moreover, a parcellation of the monkey OFC into two subdivisions has been suggested based on its intrinsic anatomical connections. However, in humans, little is known about any functional subdivisions of the OFC except for a rather coarse medial/lateral distinction. Here, we used resting-state fMRI in combination with unsupervised clustering techniques to investigate whether OFC subdivisions can be revealed based on their functional connectivity profiles with other brain regions. Examination of different cluster solutions provided support for a parcellation into two parts as observed in monkeys, but it also highlighted a much finer hierarchical clustering of the orbital surface. Specifically, we identified (1) a medial, (2) a posterior-central, (3) a central, and (4-6) three lateral clusters spanning the anterior-posterior gradient. Consistent with animal tracing studies, these OFC clusters were connected to other cortical regions such as prefrontal, temporal, and parietal cortices but also subcortical areas in the striatum and the midbrain. These connectivity patterns provide important implications for identifying specific functional roles of OFC subdivisions for reward processing, learning, and decision making. Moreover, this parcellation schema can provide guidance to report results in future studies.

Economic and Environmental Study of Wineries Powered by Grid-Connected Photovoltaic Systems in Spain

Directory of Open Access Journals (Sweden)

Daniel Gómez-Lorente

2017-02-01

Full Text Available This research developed a system that can make factories more independent from the grid. The system enhances efficiency since factory operation is powered by the renewable energy generated during the production process. Winemaking is a key sector that can profit from such a system because wineries can recycle much of the waste from the raw materials employed in wine production. Moreover, the solar energy collected at winemaking facilities can also be used to reduce electricity consumption and thus increase energy efficiency. This study investigated the feasibility of using renewable energy sources, such as solar energy, in wineries in Spain, given the quantity of renewable energy produced in the country. For this purpose, cost-effectiveness, power generation, CO2 emissions and the renewable energy fraction were taken into account. The assumption was that the photovoltaic system was grid-connected. Research results showed a reduction in electrical power costs ranging from 4% to 36%. This reduction was accompanied by an increase in the use of renewable energy of up to 57%. The results obtained are based on self-consumption or net metering policy as well as the production capacity of the winery.

Steel making

CERN Document Server

Chakrabarti, A K

2014-01-01

"Steel Making" is designed to give students a strong grounding in the theory and state-of-the-art practice of production of steels. This book is primarily focused to meet the needs of undergraduate metallurgical students and candidates for associate membership examinations of professional bodies (AMIIM, AMIE). Besides, for all engineering professionals working in steel plants who need to understand the basic principles of steel making, the text provides a sound introduction to the subject.Beginning with a brief introduction to the historical perspective and current status of steel making together with the reasons for obsolescence of Bessemer converter and open hearth processes, the book moves on to: elaborate the physiochemical principles involved in steel making; explain the operational principles and practices of the modern processes of primary steel making (LD converter, Q-BOP process, and electric furnace process); provide a summary of the developments in secondary refining of steels; discuss principles a...

National electricity planning in settings with low pre-existing grid coverage: Development of a spatial model and case study of Kenya

International Nuclear Information System (INIS)

Parshall, Lily; Pillai, Dana; Mohan, Shashank; Sanoh, Aly; Modi, Vijay

2009-01-01

We develop a spatial electricity planning model to guide grid expansion in countries with low pre-existing electricity coverage. The model can be used to rapidly estimate connection costs and compare different regions and communities. Inputs that are modeled include electricity demand, costs, and geographic characteristics. The spatial nature of the model permits accurate representation of the existing electricity network and population distribution, which form the basis for future expansion decisions. The methodology and model assumptions are illustrated using country-specific data from Kenya. Results show that under most geographic conditions, extension of the national grid is less costly than off-grid options. Based on realistic penetration rates for Kenya, we estimate an average connection cost of $1900 per household, with lower-cost connection opportunities around major cities and in denser rural regions. In areas with an adequate pre-existing medium-voltage backbone, we estimate that over 30% of households could be connected for less than $1000 per connection through infilling. The penetration rate, an exogenous factor chosen by electricity planners, is found to have a large effect on household connection costs, often outweighing socio-economic and spatial factors such as inter-household distance, per-household demand, and proximity to the national grid.

Place, Matters of Concern, and Pedagogy: Making Impactful Connections with Our Planet

Science.gov (United States)

Iorio, Jeanne Marie; Hamm, Catherine; Parnell, Will; Quintero, Elizabeth

2017-01-01

Neoliberalism, capitalist ideas, and the disastrous human-induced state of the environment are evidence of the lack of connection between humans and the earth, calling for a rethinking of the relationships between humans and the planet. As early childhood educators, we wonder about our role in rethinking these relationships and in particular, the…

Nuclear Power Plants in a Competitive Electricity Market

International Nuclear Information System (INIS)

Jankauskas, V.

2002-01-01

Electricity demand is growing in the world by an average rate of 3% and, according to the International Energy Agency, is going to keep this pace of growth for the 1st quarter of the 21st century. At the same time, the role of the nuclear in the world energy mix is diminishing, and in 2020 only 9% of the world electricity will be produced at the nuclear plants versus 17% in 2000. The main reasons for the nuclear power diminishing share in the world market are not environmental or safety problems, as one may assume, but technical and economical. Long construction time, high capital cost, huge liabilities connected with the spent nuclear fuel and radioactive waste treatment, storage and final disposal are the main factors restricting the further growth of the nuclear power. Nevertheless, in the liberalized markets (U.K., Germany, Scandinavian countries) nuclear power plants are operating rather successfully. In a short run nuclear plants may become very competitive as they have very low short-run marginal costs, but in the long run they may become very in competitive. The Ignalina NPP plays the dominant ro]e in the Lithuanian electricity market, producing more than 75% of the total domestic electricity. It produces the cheapest electricity in Lithuania, mostly due to its higher availability, than the thermal power plants. The price of electricity sold by Ignalina is also lower as it does not cover all costs connected with the future decommissioning of the plant, spent fuel storage and final disposal. If at least part of this cost were included into the selling price, Ignalina might become highly competitive in a liberalised electricity market. As the Lithuanian Electricity law requires to deregulate electricity. generation prices, these prices should be set by the market. (author)

Mechanical to electrical energy conversion by shock wave effect in a ferro-electric material

International Nuclear Information System (INIS)

David, Jean

1977-01-01

The shock wave propagation through a polarized ferroelectric ceramic changes or destroys remanent polarization and this way allows to get, in adequate electrical circuit, a volume energy of about 2 J/ cm 3 , during a time of the order of 0,4 μs; which corresponds to a peak - power of 5 MW/cm 3 . The present report has for objective to specify the optimum working conditions of this mechanical to electrical conversion from ceramic characteristics, load circuit connected to its electrodes and from the characteristics of the pressure wave which travels through the materials which constitute the converter. After a few lines about the ferroelectric materials and about the shock waves, the shock generator, the used setting and measures are described. A mathematical model which exhibits the transducer operation and a computation of the allowable electrical energy are given. For ending, the released electrical energies by industrial and laboratory ceramics are compared to the estimated computations and a thermodynamical balance is carried out. (author) [fr

Removal of Heavy Metals from Steel Making Waste Water by Using Electric Arc Furnace Slag

Directory of Open Access Journals (Sweden)

C. L. Beh

2012-01-01

Full Text Available This work investigated the reduction of chemical oxygen demand (COD, biological oxygen demand (BOD, total suspended solids (TSS and the concentration of heavy metals of wastewater from a steel making plant. Adsorption experiments were carried out by electric arc furnace slag (EAFS in a fixed-bed column mode. The raw wastewater did not meet the standard B limitations, having high values of BOD, COD, TSS, Iron, Zinc, Manganese and Copper. After passing through the fixed bed column, BOD, COD and TSS values decreased to 1.6, 6.3 and <2 mgL-1, respectively while the concentration of Iron, Zinc, Manganese and Copper were 0.08, 0.01, 0.03 and 0.07 mgL-1, respectively. The results confirmed that EAFS can be used as an efficient adsorbent for producing treated water that comply with the Standard B limitations for an industrial effluent.

Why have connection costs soared so dramatically?

International Nuclear Information System (INIS)

Bahjejian, L.

2012-01-01

Thousands of small photovoltaic power stations are demanding their connection to the national power grid. ERDF, the manager of the grid, has to adapt and reinforce some lines. The connection costs that were previously supported by the consumers has to be paid by the demander as the law NOME stipulates it. For installations below 18 kVA the cost ranges from 800 to 1600 euros and for more powerful installations an estimate has to be drawn by ERDF and the cost will depends on the presence or not of an adequate transformer in the vicinity, on the possible upgrading of the transformer, on the length of the cables necessary to make the connection and on whether the installation is in an urban area or not. A table gives the ERDF tariffs for the connection and the case of the connection of a 35 kVA station built on the roof of a shed in a rural zone is dealt with. The procedure to follow for demanding the connection to ERDF is detailed. (A.C.)

Surveying Parental Mediation: Connections, Challenges and Questions for Media Literacy

Science.gov (United States)

Mendoza, Kelly

2009-01-01

This paper examines three strategies of parental mediation--coviewing, restrictive mediation, and active mediation--in order to make connections, challenge, and raise questions for media literacy. Coviewing, whether it is intentional practice, or whether it functions to promote media literacy, is explored. Restrictive mediation, how it connects to…

An estimate of the cost of electricity production from hot-dry rock

International Nuclear Information System (INIS)

Pierce, K.G.; Livesay, B.J.

1993-01-01

This paper gives an estimate of the cost to produce electricity from hot-dry rock (HDR). Employment of the energy in HDR for the production of electricity requires drilling multiple wells from the surface to the hot rock, connecting the wells through hydraulic fracturing, and then circulating water through the fracture system to extract heat from the rock. The basic HDR system modeled in this paper consists of an injection well, two production wells, the fracture system (or HDR reservoir), and a binary power plant. Water is pumped into the reservoir through the injection well where it is heated and then recovered through the production wells. Upon recovery, the hot water is pumped through a heat exchanger transferring heat to the binary, or working, fluid in the power plant. The power plant is a net 5.1-MW e binary plant employing dry cooling. Make-up water is supplied by a local well. In this paper, the cost of producing electricity with the basic system is estimated as the sum of the costs of the individual parts. The effects on cost of variations to certain assumptions, as well as the sensitivity of costs to different aspects of the basic system, are also investigated

Neural network based photovoltaic electrical forecasting in south Algeria

International Nuclear Information System (INIS)

Hamid Oudjana, S.; Hellal, A.; Hadj Mahammed, I

2014-01-01

Photovoltaic electrical forecasting is significance for the optimal operation and power predication of grid-connected photovoltaic (PV) plants, and it is important task in renewable energy electrical system planning and operating. This paper explores the application of neural networks (NN) to study the design of photovoltaic electrical forecasting systems for one week ahead using weather databases include the global irradiance, and temperature of Ghardaia city (south of Algeria) for one year of 2013 using a data acquisition system. Simulations were run and the results are discussed showing that neural networks Technique is capable to decrease the photovoltaic electrical forecasting error. (author)

Wideband energy harvesting based on mixed connection of piezoelectric oscillators

Science.gov (United States)

Wu, P. H.; Chen, Y. J.; Li, B. Y.; Shu, Y. C.

2017-09-01

An approach for wideband energy harvesting together with power enhancement is proposed by integrating multiple piezoelectric oscillators with mixed parallel-series connection. This gives rise to the feasibility of shifting the operation frequency band to the dominant frequency domain of ambient excitations. There are two types of connection patterns discussed here: the p-type (s-type) is the parallel (series) connection of all sets of oscillators where some of them may be connected in series (parallel). In addition, the standard interface circuit used for electric rectification is adopted here. The analytic estimates of output power are derived and explicitly expressed in terms of different matrix formulations for these two connection patterns. They are subsequently validated and are found in good agreement with numerical simulations and experimental observations. Finally, the experimental results from the mixed connection of 4 piezoelectric oscillators show that the peak power of each array is about 3.4 times higher than that generated by a single piezoelectric oscillator. In addition, the bandwidth of the array capable of switching connection patterns is around 2.8 times wider than that based on a single array configuration. Hence, the effective bandwidth is enlarged without the loss of peak power.

Chaotic synchronization of three coupled oscillators with ring connection

International Nuclear Information System (INIS)

Kyprianidis, I.M.; Stouboulos, I.N.

2003-01-01

We study the evolution of three identical, resistively coupled with ring connection, nonlinear and nonautonomous electric circuits from nonsynchronized oscillations to synchronized ones, when they exhibit chaotic behavior. Phase-locked states are also observed, as the coupling parameter is varied. The system's dynamics depends on the way of coupling (unidirectional or bidirectional)

Chaotic synchronization of three coupled oscillators with ring connection

CERN Document Server

Kyprianidis, I M

2003-01-01

We study the evolution of three identical, resistively coupled with ring connection, nonlinear and nonautonomous electric circuits from nonsynchronized oscillations to synchronized ones, when they exhibit chaotic behavior. Phase-locked states are also observed, as the coupling parameter is varied. The system's dynamics depends on the way of coupling (unidirectional or bidirectional).

Decentralized electricity production. v. 1 and 2

International Nuclear Information System (INIS)

1991-01-01

The first part of the symposium is concerned with market analysis, case studies and prospectives for the decentralized production of electricity in France: cogeneration, heat networks, municipal waste incineration, etc. Financing systems and microeconomical analysis are presented. The second part is devoted to macroeconomical outlooks (France and Europe mainly) on decentralized electricity production (cogeneration, small-scale hydroelectric power plants), to other countries experience (PV systems connected to the grid, cogeneration, etc.) and to price contracts and regulations

Characteristics of magnetospheric convective electric fields as mapped onto the polar caps

International Nuclear Information System (INIS)

Saunders, R.S.

1976-01-01

A study is made of the open connected magnetosphere using two numerical computer models: the Hones-Taylor (1965), with image and internal dipoles being the only sources, and the Mead-Williams (1965) with a current sheet added. The objectives of the study are to demonstrate that steady state field line connection across the magnetopause is a possible mechanism for producing the polar cap electric fields detected there, and to show the interesting characteristics of such fields. A review of the literature pertinent to the polar cap electric fields is included

The thermo-electric nature of the Debye temperature

Directory of Open Access Journals (Sweden)

Mithun Bhowmick

2018-05-01

Full Text Available The Debye temperature is typically associated with the heat capacity of a solid and the cut-off of the possible lattice vibrations, but not necessarily to the electric conductivity of the material. By investigating III-V and II-VI compound semiconductors, we reveal that the Debye temperature represents a thermo-electric material parameter, connecting the thermal and electronic properties of a solid via a distinct power law.

Optimal sizing of a hybrid grid-connected photovoltaic and wind power system

International Nuclear Information System (INIS)

González, Arnau; Riba, Jordi-Roger; Rius, Antoni; Puig, Rita

2015-01-01

Highlights: • Hybrid renewable energy systems are efficient mechanisms to generate electrical power. • This work optimally sizes hybrid grid-connected photovoltaic–wind power systems. • It deals with hourly wind, solar irradiation and electricity demand data. • The system cost is minimized while matching the electricity supply with the demand. • A sensitivity analysis to detect the most critical design variables has been done. - Abstract: Hybrid renewable energy systems (HRES) have been widely identified as an efficient mechanism to generate electrical power based on renewable energy sources (RES). This kind of energy generation systems are based on the combination of one or more RES allowing to complement the weaknesses of one with strengths of another and, therefore, reducing installation costs with an optimized installation. To do so, optimization methodologies are a trendy mechanism because they allow attaining optimal solutions given a certain set of input parameters and variables. This work is focused on the optimal sizing of hybrid grid-connected photovoltaic–wind power systems from real hourly wind and solar irradiation data and electricity demand from a certain location. The proposed methodology is capable of finding the sizing that leads to a minimum life cycle cost of the system while matching the electricity supply with the local demand. In the present article, the methodology is tested by means of a case study in which the actual hourly electricity retail and market prices have been implemented to obtain realistic estimations of life cycle costs and benefits. A sensitivity analysis that allows detecting to which variables the system is more sensitive has also been performed. Results presented show that the model responds well to changes in the input parameters and variables while providing trustworthy sizing solutions. According to these results, a grid-connected HRES consisting of photovoltaic (PV) and wind power technologies would be

Cross-border effects of capacity mechanisms in electricity markets

International Nuclear Information System (INIS)

Elberg, Christina

2014-01-01

To ensure security of supply in liberalized electricity markets, different types of capacity mechanisms are currently being debated or have recently been implemented in many European countries. The purpose of this study is to analyze the cross-border effects resulting from different choices on capacity mechanisms in neighboring countries. We consider a model with two connected countries that differ in the regulator's choice on capacity mechanism, namely strategic reserves or capacity payments. In both countries, competitive fi rms invest in generation capacity before selling electricity on the spot market. We characterize market equilibria and find the following main result: While consumers' costs may be the same under both capacity mechanisms in non-connected countries, we show that the different capacity mechanisms in interconnected countries induce redistribution effects. More precisely, we nd that consumers' costs are higher in countries in which reserve capacities are procured than in countries in which capacity payments are used to ensure the targeted reliable level of electricity.

Cross-border effects of capacity mechanisms in electricity markets

Energy Technology Data Exchange (ETDEWEB)

Elberg, Christina

2014-07-15

To ensure security of supply in liberalized electricity markets, different types of capacity mechanisms are currently being debated or have recently been implemented in many European countries. The purpose of this study is to analyze the cross-border effects resulting from different choices on capacity mechanisms in neighboring countries. We consider a model with two connected countries that differ in the regulator's choice on capacity mechanism, namely strategic reserves or capacity payments. In both countries, competitive fi rms invest in generation capacity before selling electricity on the spot market. We characterize market equilibria and find the following main result: While consumers' costs may be the same under both capacity mechanisms in non-connected countries, we show that the different capacity mechanisms in interconnected countries induce redistribution effects. More precisely, we nd that consumers' costs are higher in countries in which reserve capacities are procured than in countries in which capacity payments are used to ensure the targeted reliable level of electricity.

Make2Learn with IoT: Engaging children into joyful design and making of interactive connected objects

DEFF Research Database (Denmark)

Divitini, Monica; Giannakos, Michail; Mora, Simone

2017-01-01

of the art aspects of learning technologies, Make2learn aims to develop a critical discussion about the well-established practices and technologies and how different tool and methods can be put into practice under different spaces such as the classroom, makerspaces, fablabs, etc. During the workshop a set...... and improve the value of Maker philosophy and the role of design and making IoT technologies to support teaching and learning....

The physical foundation of the reconnection electric field

Science.gov (United States)

Hesse, M.; Liu, Y.-H.; Chen, L.-J.; Bessho, N.; Wang, S.; Burch, J. L.; Moretto, T.; Norgren, C.; Genestreti, K. J.; Phan, T. D.; Tenfjord, P.

2018-03-01

Magnetic reconnection is a key charged particle transport and energy conversion process in environments ranging from astrophysical systems to laboratory plasmas [Yamada et al., Rev. Mod. Phys. 82, 603-664 (2010)]. Magnetic reconnection facilitates plasma transport by establishing new connections of magnetic flux tubes, and it converts, often explosively, energy stored in the magnetic field to kinetic energy of charged particles [J. L. Burch and J. F. Drake, Am. Sci. 97, 392-299 (2009)]. The intensity of the magnetic reconnection process is measured by the reconnection electric field, which regulates the rate of flux tube connectivity changes. The change of magnetic connectivity occurs in the current layer of the diffusion zone, where the plasma transport is decoupled from the transport of magnetic flux. Here we report on computer simulations and analytic theory to provide a self-consistent understanding of the role of the reconnection electric field, which extends substantially beyond the simple change of magnetic connections. Rather, we find that the reconnection electric field is essential to maintain the current density in the diffusion region, which would otherwise be dissipated by a set of processes. Natural candidates for current dissipation are the average convection of current carriers away from the reconnection region by the outflow of accelerated particles, or the average rotation of the current density by the magnetic field reversal in the vicinity. Instead, we show here that the current dissipation is the result of thermal effects, underlying the statistical interaction of current-carrying particles with the adjacent magnetic field. We find that this interaction serves to redirect the directed acceleration of the reconnection electric field to thermal motion. This thermalization manifests itself in form of quasi-viscous terms in the thermal energy balance of the current layer. This collisionless viscosity, found in the pressure evolution equation

Tariffs on power supply and prices of electricity per 1st January 1994

International Nuclear Information System (INIS)

1994-04-01

The document gives a survey of the most usual types of tariffs connected with the Danish electric-power distribution companies and the prices, valid per January 1st, 1994, set by individual companies and also the cost to consumers of connection to the supply network. A survey of prices set by power plant administrators with regard to the distribution companies is also included in addition to a summary of the modes of calculation in connection with wind turbines not owned by the electricity companies and descriptions of models for calculations related to decentral and industrial plants. Local conditions such as structure, economy etc. must be taken into consideration when comparing prices set by companies in several different areas. (AB)

Interconnection of industrial centers with the electric network of the public service; Interconexion de centros industriales con la red electrica del servicio publico

Energy Technology Data Exchange (ETDEWEB)

Rosales Sedano, Inocente; Lopez Velazquez, Juan Jose; Garcia Paredes, Job; Robles Pimentel, Edgar [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico); Garcia Alvarez, David; Guzman Camacho, Benigno [Petroleos Mexicanos (Mexico)

2000-07-01

The large industrial centers that have continuous production processes and consume high amounts of electrical energy, generally have their own power generation. The petrochemical complexes, the paper and steel factories and the sugar mills are examples of this type of centers. On the other hand, the new regulation for the generation of electrical energy that allows to the electrical energy interchange between private companies and the public network, has originated the necessity of connecting systems that formerly operated isolated. Since the original design of the isolated electrical systems was to operate in an independent form, making the interconnection can generate technical problems that must be analyzed and solved. In this paper, some experiences related with the behavior of electrical equipment when connected to operate with the public network, are presented. [Spanish] Los grandes centros industriales que tienen procesos de produccion continua y consumen altas cantidades de energia electrica, generalmente cuentan con generacion propia. Los complejos petroquimicos, las fabricas de papel y acero y los ingenios azucareros son ejemplos de este tipo de centros. Por otro lado, la nueva reglamentacion de generacion de energia electrica que permite el intercambio de energia electrica entre las companias privadas y la red publica, ha originado la necesidad de conectar sistemas que antes operaban aislados. Debido a que el diseno original de los sistemas electricos aislados fue trabajar en forma independiente, el realizar la interconexion puede generar problemas tecnicos que tienen que analizarse y resolverse. En este articulo, se presentan algunas experiencias relacionadas con el comportamiento del equipo electrico al operar conectado con la red publica.

Performance of Grid-Connected Photovoltaic System in Two Sites in Kuwait

Directory of Open Access Journals (Sweden)

Ali Hajiah

2012-01-01

Full Text Available This paper presents an assessment of the electricity generated by photovoltaic (PV grid-connected systems in Kuwait. Three years of meteorological data are provided for two main sites in Kuwait, namely, Al-Wafra and Mutla. These data and a PV grid-connected system mathematical model are used to assist a 100 kWp grid-connected PV system proposed for both sites. The proposed systems show high energy productivity whereas the annual capacity factors for Mutla and Al-Wafra are 22.25% and 21.6%, respectively. Meanwhile the annual yield factors for Mutla and Al-Wafra are 1861 kWh/kWp/year and 1922.7 kWh/kWp/year, respectively. On the other hand the cost of the energy generated by both systems is about 0.1 USD/kWh which is very close to the price of the energy sold by the Ministry of Electricity and Water (MEW. Furthermore the invested money is recovered during the assumed life cycle time whereas the payback period for both sites is about 15 years. This work contains worthwhile technical information for those who are interested in PV technology investment in Kuwait.

Evaluation and comparison of electric propulsion motors for submarines

OpenAIRE

Harbour, Joel P.

2001-01-01

CIVINS (Civilian Institutions) Thesis document The Navy has announced its conviction to make its warships run on electric power through the decision to make its newest line of destroyers propelled with an electric propulsion system. Several ship construction firms and electric motor manufacturers are thus striving to develop enabling technology, including high power density motors. The purpose of this thesis is to evaluate some of the proposed motor designs for use in a submarine. Permanen...

PV solar electricity: status and future

Science.gov (United States)

Hoffmann, Winfried

2006-04-01

Within the four main market segments of PV solar electricity there are already three areas competitive today. These are off-grid industrial and rural as well as consumer applications. The overall growth within the past 8 years was almost 40 % p.a. with a "normal" growth of about 18 % p.a. for the first three market segments whereas the grid connected market increased with an astonishing 63 % p.a. The different growth rates catapulted the contribution of grid connected systems in relation to the total market from about one quarter 6 years ago towards more than three quarters today. The reason for this development is basically due to industry-politically induced market support programs in the aforementioned countries. It is quite important to outline under which boundary conditions grid connected systems will be competitive without support programs like the feed in tariff system in Germany, Spain and some more to come in Europe as well as investment subsidies in Japan, US and some other countries. It will be shown that in a more and more liberalized utility market worldwide electricity produced by PV solar electricity systems will be able to compete with their generating cost against peak power prices from utilities. The point of time for this competitiveness is mainly determined by the following facts: 1. Price decrease for PV solar electricity systems leading to an equivalent decrease in the generated cost for PV produced kWh. 2. Development of a truly liberalized electricity market. 3. Degree of irradiation between times of peak power demand and delivery of PV electricity. The first topic is discussed using price experience curves. Some explanations will be given to correlate the qualitative number of 20 % price decrease for doubling cumulative worldwide sales derived from the historic price experience curve with a more quantitative analysis based on our EPIA-Roadmap (productivity increase and ongoing improvements for existing technologies as well as development

Energy management for vehicle power net with flexible electric load demand

NARCIS (Netherlands)

Kessels, J.T.B.A.; Bosch, van den P.P.J.; Koot, M.W.T.; Jager, de A.G.

2005-01-01

The electric power demand in road vehicles increases rapidly and to supply all electric loads efficiently, energy management (EM) turns out to be a necessity. In general, EM exploits the storage capacity of a buffer connected to the vehicle's power net, such that energy is stored or retrieved at

Connecting and disconnecting nematic disclination lines in microfluidic channels.

Science.gov (United States)

Agha, Hakam; Bahr, Christian

2016-05-14

Disclination lines in nematic liquid crystals can be used as "soft rails" for the transport of colloids or droplets through microfluidic channels [A. Sengupta, C. Bahr and S. Herminghaus, Soft Matter, 2013, 9, 7251]. In the present study we report on a method to connect and disconnect disclination lines in microfluidic channels using the interplay between anchoring, flow, and electric field. We show that the application of an electric field establishes a continuous disclination that spans across a channel region in which a disclination usually would not exist (because of different anchoring conditions), demonstrating an interruptible and reconnectable soft rail for colloidal transport.

In Situ TEM Electrical Measurements

DEFF Research Database (Denmark)

Canepa, Silvia; Alam, Sardar Bilal; Ngo, Duc-The

2016-01-01

understanding of complex physical and chemical interactions in the pursuit to optimize nanostructure function and device performance. Recent developments of sample holder technology for TEM have enabled a new field of research in the study of functional nanomaterials and devices via electrical stimulation...... influence the sample by external stimuli, e.g. through electrical connections, the TEM becomes a powerful laboratory for performing quantitative real time in situ experiments. Such TEM setups enable the characterization of nanostructures and nanodevices under working conditions, thereby providing a deeper...... and measurement of the specimen. Recognizing the benefits of electrical measurements for in situ TEM, many research groups have focused their effort in this field and some of these methods have transferred to ETEM. This chapter will describe recent advances in the in situ TEM investigation of nanostructured...