Cleaning oil refining drainage waters out of emulsified oil products with thermic treated cedar nut shell

Science.gov (United States)

Pyatanova, P. A.; Adeeva, L. N.

2017-08-01

It was elaborated the ability of the sorbent produced by thermic treatment of cedar nut shell to destruct model and real first kind (direct) emulsions in static and dynamic conditions. In static conditions optimal ratio sorbent-emulsion with the original concentration of oil products 800 mg/l was in the range of 2.0 g per 100 ml of emulsion which corresponds to the level of treatment 94.9%. The time of emulsion destruction was 40 minutes. This sorbent is highly active in dynamic processes of oil-contaminated water treatment, the level of treatment 96.0% is being achieved. Full dynamic sorptive capacity of the sorbent is 0.85 g/g. Sorbent based on the thermic treated cedar nut shell can be elaborated as sorptive filter element of local treatment facilities of oil refining and petrochemical processes. After the treatment with this sorbent of drainage waters of oil refinery in dynamic conditions the concentration of oil products became less than mpc on oil products for waste waters coming to biological treatment.

Thermic Attenuation on Concrete Sidewalk under Urban Trees. Case Study: Santa Marta – Colombia

OpenAIRE

Carlos Devia; Andrés Torres

2012-01-01

Background and Purpose: Urban trees provide a number of services including shade and thermal attenuation. This is related to morphological and physiological characteristics of trees and may vary between species and even between individuals of the same species. The aim of this work was to identify thermic attenuations on concrete sidewalks under six tropical urban trees with six different types of shadows. Material and Methods: In Santa Marta City, Colombia (10º12´20” N, 74º13´33” W, 10 met...

Planning model for hydraulic and thermic generation systems expansion under uncertainly conditions and financial restrictions; Modelo de planejamento da expansao de sistemas hidrotermicos sob incertezas e restricoes financeiras

Energy Technology Data Exchange (ETDEWEB)

Gorenstin, B.G.; Costa, J.P. da [CEPEL, Rio de Janeiro, RJ (Brazil); Pereira, M.V.F.; Campodonico, N.M.

1993-12-31

This issue presents a methodology for planning the systems expansion of hydraulic and thermic power generation associated considering several uncertainly factors, such as: demand growing, fuel costs, delays on the work construction, financial restrictions, etc. The solution focus is based on stock optimize techniques, decision analysis. This work is being developed by the Brazilian Electrical Centre (ELETROBRAS) and rely on the Energy Latin-American Organization (OLADE), Development Inter-American Bank (BID), World Bank (BIRD) and International Energy Agency (IAEA) support. An example case with Costa Rica system is also discussed 19 refs., 4 figs., 2 tabs.

Report on thermic effects in the study of the control and propagation of nuclear reactions

International Nuclear Information System (INIS)

Naudet, R.

It is very likely that nuclear reactions in natural reactors are governed by temperature, chiefly as a result of the moderation rate when the water density is altered. Since reactors operate under high pressure, with supercritical water, high temperatures (at least 350 to 400 0 C in some instances) are required in order to stabilize the reactors. Some typical calculations are shown in order to illustrate the changes in the control temperature during irradiation. The speed and, therefore, the duration of reactions is determined by the need to maintain the necessary temperature required for criticality, with heat dissipation conditions taken into account. Apparent measured durations are compatible with heat dissipation by simple conduction. However, it is likely that convection currents exist, and that their effects are superimposed on those of simple conduction. Reaction propagation must also be taken into consideration since criticality cannot be realized simultaneously at every point. The presence of impurities such as gadolinium or samarium in the mineral ore allows reactions to propagate in initially subcritical increments, through progressive breakdown of the impurities by means of neutronic diffusion. However, it has been shown that this phenomenon is seriously affected by thermic effects. Typical calculations are presented. Results clearly depend on temperature distribution hypotheses; sufficient thermic coupling can totally inhibit reaction propagation. It is concluded that, if convection currents are present, propagation is favored inversely with respect to the currents, and therefore a priori downstream of the reactors. 6 figures

Aspects of Energy Metabolism in Mangalitsa Pigs Exposed at Thermic Neutral Temperature

Directory of Open Access Journals (Sweden)

Monica Pârvu

2011-10-01

Full Text Available The studies aimed the energy metabolism determination in Mangalitsa pigs exposed at thermic neutral temperature, compared to Large White pigs. The experimental period was between 80 and 100 kg liveweight. The animals had free access to standard, isoprotein and isocalory diets, with 13.5% crude protein (CP and 3100 kcal/kg metabolizable energy. Feed intake was measured on a daily basis. The energy-protein balance was calculated on the basis of comparative slaughter made at the beginning and end of the experiment. The metabolizable energy (MEc was estimated by chemical analysis (feed and excreta using mathematical modelling and the Whittemore’s formula. The metabolizable energy utilization efficiency was 0.61 at Large White and 0.53 at Mangalitsa.

Antifoaming materials studies in G.S. (Girlder sulfide) heavy water plants. Chemical and thermical stability. Pt. 3

International Nuclear Information System (INIS)

Delfino, C.A.; Rojo, E.A.

1988-01-01

In Girlder sulfide (G.S.) heavy water plants hydrogen sulfide-water systems are inherentely foaming, so the adding of antifoaming materials is of great importance. These may be of high volatility, pyrolizable or chemically unstable in plant operation conditions (water and hydrogen sulfide at 2 MPa, up to 230 deg C). Five commercial surfactants were studied from the point of view of their chemical and thermical stability in order to select the most suitable. (Author) [es

Magnesio-thermic reduction of UF4 to uranium metal : plant operating experience

International Nuclear Information System (INIS)

Mayekar, S.V.; Singh, H.; Meghal, A.M.; Koppiker, K.S.

1991-01-01

Uranium Metal Plant has switched over from calcio-thermy to magnesio-thermy for production of uranium ingots. In this paper, the plant operating experience for magnesio-thermic reduction is described. Based on trials, the production has been stepped up from 40 kg ingots to 200 kg ingots. The operating parameters optimised include : heating schedule, UF 4 quality, magnesium quantity and quality, and particle size. The effect of quality of refractory lining has been discussed. Conditions for lining are optimised with regard to type of material used and size. Developmental work has also been carried out on use of pelletised charge and on use of graphite sleeves. Some experience in the machining of ingots for removal of surface slag is also discussed. Impurity problems, occasionally encountered, have been investigated and results are discussed. Based on the experience gained, specifications for operation have been laid down, and areas for further improvement are identified. (author). 5 refs., 1 fig., 1 tab

Modern biofuel-fired power plants in power and heat production

International Nuclear Information System (INIS)

Tuominen, J.

1993-01-01

This article gives a survey of the gasification techniques, power plant technology and boiler solutions for small power plants using biofuels. Also some experiences from commercial projects and targets of development work are presented. At present, fluidized bed combustion is by far the most important combustion technique for biomass fuels in small power plants. Compared with grate combustion, fluidized bed combustion is a distinctly more economical combustion method, and so the thermic dimensioning of a steam boiler is easier. Besides, a wider range of fuels can be used in fluidized bed combustion. Fluidized bed combustion is an excellent combustion technique for biofuels. Plenty of experience has been gained in the combustion of peat and industrial waste wood, as far as both bubbling fluidized bed combustion (BFBC) and circulating fluidized bed combustion (CFBC) are concerned. Both of the fluidized bed techniques are suitable for the combustion of biomasses

Theoretical experimental study of the factors that govern the molybdenum absorption signal by means of electro thermic atomic absorption spectroscopy

International Nuclear Information System (INIS)

Garaboto Farfan, M. A.

1996-01-01

The formation of molybdenum carbides in the atomizer, used in the electro thermic atomic absorption spectroscopy, is responsible for incomplete analyte removal in its analysis. This generates the apparition of the memory effect and little precision in the results. In this work, different variables that could affect the molybdenum absorption sign were investigated, as well as the influence of hydrochloric acid on the memory effect, by means of studies in the different stages: drying, calcination and atomization, and the samples deposition order in molybdenum solutions, either acidified or not acidified [es

The effect of fast eating on the thermic effect of food in young Japanese women.

Science.gov (United States)

Toyama, Kenji; Zhao, Xifan; Kuranuki, Sachi; Oguri, Yasuo; Kashiwa Kato, Eriko; Yoshitake, Yutaka; Nakamura, Teiji

2015-03-01

The relationship between eating speed and the thermic effect of food (TEF) remains unclear. We investigated the difference in the TEF when meals containing the same amount of energy were eaten in 5 min (fast eating) or 15 min (regular eating). Subjects were nine non-obese young women. Following a 350 kcal (1464 kJ) meal, energy expenditure and autonomic nervous system activity were measured. The frequency of mastication was also calculated. The TEF for the 15-min period after the start of eating with fast eating was significantly lower than with regular eating (p frequency/high-frequency ratio and TEF at 5-min intervals up to 20 min after the start of eating and between total mastication frequency and TEF during ingestion. Fast eating may reduce the TEF, potentially because a decrease in mastication frequency decreases sympathetic nervous system activity.

Thermical Load Calculation and Capacity of Cooling and Venting Equipment of a Diesel Engine Emissions Study Bench; Calculo de Cargas Termicas y Capacidad de los Equipos de Refrigeracion y Ventilacion de un Banco de Estudio de Emisiones de Motores Diesel

Energy Technology Data Exchange (ETDEWEB)

Rojas Garcia, E.; Fonseca Gonzalez, N. A.

2005-07-01

The present report tries to develop the calculation of thermical loads and to define the capacity of the equipments of cooling and ventilation that should have the engines test bench that is being ensemble in the installation of the CIEMAT named {sup D}iesel engine emissions study bench (E65-P0). The test bench is formed essentially by a dynamometrical brake and an engine connected at previous one, both of them inside a cabin of isolation acoustic. The thermical loads to be dissipated will be calculated for all the elements that compose the bench and considering his maximum values, to determine the suitable system of cooling air - water of the devices and ventilation in the cabin. (Author) 2 refs.

Monitoring and assessment of thermical comfort in hygrothermically moderate offices and laboratories; Monitoraggio e valutazione del comfort termico negli ambienti di lavoro termoigrometricamente moderati

Energy Technology Data Exchange (ETDEWEB)

Speranza, A. [ENEA, Centro Ricerche `Ezio Clementel`, Bologna (Italy). Dip. Ambiente

1998-12-31

This study reports the results of the micro climatic measurements carried out in some ENEA work environments. The work conditions in the surveyed areas, have been evaluated following welfare indexes or thermical comfort: PMV= Predicted Mean Vote (ISO recommendation 7730); PPD= Predicted Percentage of Dissatisfied (ISO recommendation 7730). [Italiano] In questo studio sono riportati i risultati delle misure microclimatiche eseguite in alcuni ambienti di lavoro dei centri ENEA di Bologna. Le condizioni di lavoro (delle zone che sono state sottoposte ad indagine) sono state valutate mediante i seguenti indici di benessere o `comfort` termico: Voto Medio Previsto (PMV= Predicted Mean Vote) - raccomandazione ISO 7730; Percentuale Prevista di Insoddisfatti (PPD= Predicted Percentage of Dissatisfied) - raccomandazione ISO 7730.

Monitoring and assessment of thermical comfort in hygrothermically moderate offices and laboratories; Monitoraggio e valutazione del comfort termico negli ambienti di lavoro termoigrometricamente moderati

Energy Technology Data Exchange (ETDEWEB)

Speranza, A [ENEA, Centro Ricerche ` Ezio Clementel` , Bologna (Italy). Dip. Ambiente

1999-12-31

This study reports the results of the micro climatic measurements carried out in some ENEA work environments. The work conditions in the surveyed areas, have been evaluated following welfare indexes or thermical comfort: PMV= Predicted Mean Vote (ISO recommendation 7730); PPD= Predicted Percentage of Dissatisfied (ISO recommendation 7730). [Italiano] In questo studio sono riportati i risultati delle misure microclimatiche eseguite in alcuni ambienti di lavoro dei centri ENEA di Bologna. Le condizioni di lavoro (delle zone che sono state sottoposte ad indagine) sono state valutate mediante i seguenti indici di benessere o `comfort` termico: Voto Medio Previsto (PMV= Predicted Mean Vote) - raccomandazione ISO 7730; Percentuale Prevista di Insoddisfatti (PPD= Predicted Percentage of Dissatisfied) - raccomandazione ISO 7730.

Reinforcement of the radiative and thermic stresses of the grapevine. Repercussions on yeast surface microflora

International Nuclear Information System (INIS)

Salmon, J.M.; Mailhac, N.; Sauvage, F.X.; Biron, M.J.; Robin, J.P.

1997-01-01

All along the ripening period, the radiative and thermic stresses of the grapevine may be reinforced by the use of a reflective soil cover (aluminized film). Such a treatment leads to repercussions on the berries, on the must composition and finally on the wine quality. During such a preliminary experiment, we demonstrated that the temperature increase and/or the reinforcement of the reflected ultraviolet radiations (measured at 254 nm) at the level of grape berries severely impaired the development of yeast cells at their surfaces. By means of an artificial inoculation of grapes at the beginning of the ripening period with a mixture of four different yeast genera (Saccharomyces cerevisiae, Hanseniaspora uvarum, Pichia fermentans and Schizosaccharomyces pombe), we demonstrated that the repartition of yeast genera amongst this population was affected by the treatment of stocks with the aluminized film: during the experiment presented in this paper, the Saccharomyces genus was favoured. One may consider by extension similar effects resulting from the reflective properties of some natural soils. Such effects may considerably influence the distribution of wild yeast flora during the spontaneous fermentation of musts. If such an hypothesis is confirmed at a local or regional level, it will represent a first significant piece of the definition of one of the aspects of the ''terroir'' effect on the characteristics of wines [fr

Effect of meal frequency on the thermic effect of food in women.

Science.gov (United States)

Kinabo, J L; Durnin, J V

1990-05-01

The effect of meal frequency on the thermic effect of food (TEF), also referred to as dietary induced thermogenesis (DIT), was investigated in eighteen non-obese female subjects. Their metabolic rate before and after consuming the test meal was measured by open circuit indirect calorimetry using the Douglas bag technique, while the subjects were in the resting state (lying down). Eight subjects consumed a high carbohydrate-low fat (HCLF) meal providing 70, 19 and 11 per cent of the energy content from carbohydrate, fat and protein, respectively, and ten other subjects consumed a low carbohydrate-high fat (LCHF) meal providing 24, 65 and 11 per cent of the energy from carbohydrate, fat and protein, respectively. On two separate occasions, each subject consumed the appropriate diet either as one large meal containing 5040 kJ (1200 kcal) or as two smaller meals each containing 2520 kJ (600 kcal). TEF values were calculated for 6 h after the test meal and the mean values after consuming the HCLF meal were 377.0 +/- 30.0 kJ (90 +/- 7.2 kcal) and 381.0 +/- 26.5 kJ (91.0 +/- 6.3 kcal) for the one meal and the two meals, respectively. The mean TEF values for the subjects who consumed the LCHF meal wre 356.0 +/- 23.0 kJ (85.0 +/- 5.5 kcal) and 340 +/- 15.9 kJ (81.0 +/- 3.8 kcal) for the one meal and the two meals, respectively. No significant differences were found between the two feeding regimens (HCLF, P = 0.94; LCHF, P = 0.64) as well as between the compositions (P = 0.57). Thus, meal frequency and meal composition did not seem to influence the TEF.

Reinforcement of the radiative and thermic stresses of the grape vine. Repercussions on yeast surface microflora

Directory of Open Access Journals (Sweden)

Jean-Michel Salmon

1997-12-01

Full Text Available All along the ripening period, the radiative and thermic stresses of the grapevine may be reinforced by the use of a reflective soil cover (aluminized film. Such a treatment leads to repercussions on the berries, on the must composition and finally on the wine quality. During such a preliminary experiment, we demonstrated that the temperature increase and/or the reinforcement of the reflected ultraviolet radiations (measured at 254 nm at the level of grape berries severely impaired the development of yeast cells at their surfaces. By means of an artificial inoculation of grapes at the beginning of the ripening period with a mixture of four different yeast genera (Saccharomyces cerevisiae, Hanseniaspora uvarum, Pichiafermentans and Schizosaccharomyces pombe, we demonstrated that the repartition of yeast genera amongst this population was affected by the treatment of stocks with the aluminized film: during the experiment presented in this paper, the Saccharomyces genus was favoured. One may consider by extension similar effects resulting from the reflective properties of some natural soils. Such effects may considerably influence the distribution of wild yeast flora during the spontaneous fermentation of musts. If such an hypothesis is confirmed at a local or regional level, it will represent a first significant piece of the definition of one of the aspects of the" terroir" effect on the characteristics of wines.

Contribution of data processing to technical management of PWR power plants

International Nuclear Information System (INIS)

Damestoy, J.P.

1982-01-01

In this article are reviewed the equipment used for data processing by local computer and main applications in documentation management, maintenance, daily dosimetry, monitoring, neutronic and thermics computation, material, effluents etc.. [fr

Thorough Mastication Prior to Swallowing Increases Postprandial Satiety and the Thermic Effect of a Meal in Young Women.

Science.gov (United States)

Komai, Naho; Motokubota, Naoko; Suzuki, Maki; Hayashi, Ikuyo; Moritani, Toshio; Nagai, Narumi

2016-01-01

There is evidence to support that mastication may contribute to the prevention of weight gain via reduction of appetite sensations and subsequent energy intake. However, the metabolic effect of mastication after consumption of a daily meal, composed of the staple food (rice), soup, main and side dishes, is limited. Therefore, the effect of thorough mastication on greater satiety and the thermic effect of a meal (TEM) was investigated in young women. In study 1, energy expenditure (EE) derived from masticatory muscle activity for 20 min was measured while chewing hard, tasteless, non-caloric gum in seven subjects. In study 2, ten subjects consumed a solid meal performing 30 chews per mouthful (30 CPM), or swallowed the same, pureed meal without chewing (0 CPM) on two separate days, and postprandial EE, substrate oxidation, subjective appetite ratings and autonomic nervous system (ANS) activity for 3 h were examined. Both test meals were iso-caloric (2,510 kJ) and -weighted (884 g), and consumed in 20 min. From study 1, the EE of mastication itself for the 20 min was estimated to be 3.7±0.8 kJ. From study 2, significantly higher TEM (134.2±15.5 vs. 67.8±13.8 kJ/3 h, pmastication before swallowing increased postprandial satiety and the TEM in young women, suggesting such eating behavior may be useful for preventing obesity.

Electrochemical investigation of thermically treated graphene oxides as electrode materials for vanadium redox flow battery

International Nuclear Information System (INIS)

Di Blasi, O.; Briguglio, N.; Busacca, C.; Ferraro, M.; Antonucci, V.; Di Blasi, A.

2015-01-01

Highlights: • Graphene oxide is synthesized at high temperatures in a reducing environment. • Treated graphene oxide-based electrodes are prepared by the wet impregnation method. • Electrochemical performance is evaluated as a function of the physico-chemical properties. - Abstract: Thermically treated graphene oxides (TT-GOs) are synthesized at different temperatures, 100 °C, 150 °C, 200 °C and 300 °C in a reducing environment (20% H 2 /He) and investigated as electrode materials for vanadium redox flow battery (VRFB) applications. The treated graphene oxide-based electrodes are prepared by the wet impregnation method using carbon felt (CF) as support. The main aim is to achieve a suitable distribution of the dispersed graphene oxides on the CF surface in order to investigate the electrocatalytic activity for the VO 2+ /VO 2 + and V 2+ /V 3+ redox reactions in the perspective of a feasible large area electrodes scale-up for battery configuration of practical interest. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) are carried out in a three electrode half-cell to characterize the electrochemical properties of the TT-GO-based electrodes. Physico-chemical characterizations are carried out to corroborate the electrochemical results. The TT-GO sample treated at 100 °C (TT-GO-100) shows the highest electrocatalytic activity in terms of peak to peak separation (ΔE = 0.03 V) and current density intensity (∼0.24 A cm −2 at 30 mV/s) both toward the VO 2+ /VO 2 + and V 2+ /V 3+ redox reactions. This result is correlated to the presence of hydroxyl (−OH) and carboxyl (−COOH) species that act as active sites. A valid candidate is individuated as effective anode and cathode electrode in the perspective of electrodes scale-up for battery configuration of practical interest

Impact of phenylketonuria type meal on appetite, thermic effect of feeding and postprandial fat oxidation.

Science.gov (United States)

Alfheeaid, Hani; Gerasimidis, Konstantinos; Năstase, Ana-Maria; Elhauge, Mie; Cochrane, Barbara; Malkova, Dalia

2017-03-08

Dietary management of phenylketonuria (PKU) requires the replacement of natural protein-containing foods with special low protein foods. The effect of a PKU type diet on factors contributing to energy balance requires investigation. To investigate the impact of a PKU type meal on appetite ratings, gut appetite hormones, thermic effect of feeding (TEF) and fat oxidation. Twenty-three healthy adults (mean ± SD age: 24.3 ± 5.1 years; BMI: 22.4 ± 2.5 kg/m 2 ) participated in a randomized, crossover design study. Each participant conducted two (PKU and Control) experimental trials which involved consumption of a PKU type meal and protein substitute drink or an isocaloric and weight matched ordinary meal and protein-enriched milk. Appetite, metabolic rate, fat oxidation measurements and blood collections were conducted for the duration of 300 min. On the completion of the measurements ad libitum buffet dinner was served. Responses of appetite ratings, plasma concentrations of GLP-1 and PYY (P > 0.05, trial effect, two-way ANOVA) and energy intake during ad libitum buffet dinner (P > 0.05, paired t-test) were not significantly different between the two trials. The TEF (PKU, 10.2 ± 1.5%; Control, 13.2 ± 1.0%) and the total amount of fat oxidized (PKU, 18.90 ± 1.10 g; Control, 22.10 ± 1.10 g) were significantly (P meal period. Consumption of a meal composed of special low protein foods has no detrimental impact on appetite and appetite hormones but produces a lower TEF and postprandial fat oxidation than an ordinary meal. These metabolic alterations may contribute to the increased prevalence of obesity reported in patients with PKU on contemporary dietary management. The trial has been registered in ClinicalTrials as NCT02440932. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Earth thermics

Energy Technology Data Exchange (ETDEWEB)

Ueda, M

1960-01-01

The thermodynamics of the Earth are described, including terrestrial heat flow, internal temperatures and thermal history. The value of the geothermal gradient has been considered to be 3/sup 0/C/100 m but measured values are slightly different. The values of terrestrial heat flow are relatively constant and are calculated be about 2.3 x 10 to the minus 6 cal/cm/sup 2/ sec (2.3 HFU). The Earth's internal temperature can be calculated from the adiabatic temperature gradient of adiabatic expansion. Using Simon's equation No. 9, a value of 2100-2500/sup 0/C is obtained, this is much lower than it was previously thought to be. The value of 2.3 HFU can easily be obtained from this internal temperature figure.

Control of Self Burning in Coal, Piles by Detection of the generated gases; Control de autoencendidos en Parvas de Carbon por Deteccion de los Gases Producidos

Energy Technology Data Exchange (ETDEWEB)

1999-09-01

The purpose of this Research Project is to find the most appropriate method for immediate and remote detection of the phenomena that take place in Thermic Power Plant coal piles, due to the piling up of great quantities of this fuel and its large surface area. These phenomena are: Slow self-oxidation of the coal, producing loss of its calorific power, with its consequent financial loss. Self-combustion of the coal caused when the gases produced by self-oxidation and temperature conditions combine, and they reach a critical point (that of ignition). One of the most recent and novel methods for detection is the Formation of images of Gases, based on the use of laser turned into the vibration wavelengths of the molecules in the gases. This technique, coupled with Thermography, would give as a spatial map of thus distribution and temperatures of gave. It is necessary, in order to extend the use of this equipment to Thermic Power Plant coal piles, to accurately determine which different gases are emanated as well as the minimum concentration of each one of these and the temperature distribution in space. (Author)

A GIS TOOL TO EVALUATE THE SPATIAL EVOLUTION OF HYDRO-THERMIC FEATURES DURING GROWING SEASON OF VEGETABLE CROPS IN ELBE RIVER LOWLAND (POLABI

Directory of Open Access Journals (Sweden)

VERA POTOP

2012-11-01

Full Text Available A GIS tool to evaluate the spatial evolution of hydro-thermic features during growing season of vegetable crops in Elbe River lowland (Polabi. This article presents the results of the first study on combined mezoclimatological, microclimatological and topographical tools for evaluating precision farming in the growth of vegetable crops in the Elbe River lowland (Polabi region from the Czech Republic. We assess the variability of basically climatological characteristics in relation to topographic characteristics at the regional (Polabi and local (agricultural farm scales. At regional scale, interpolation approach is based on local linear regression and universal kriging interpolation. At local scale, two conventional interpolation methods, spline and local ordinary kriging with a Gaussian model variance across the fields, were applied. The local spline interpolators have been used in developing digital elevation models (DEMs and to determine the slope angle inclination of vegetable fields. The DEMs of the vegetable crops fields was developed at a 10 m x 10 m resolution based on elevation data collected in the field by a hand-held RTK- Global Positioning System receiver. This tool allowed the distinction of microclimatic conditions that produce altitude-slope-related patterns of the spatial-temporal distribution of the basic meteorological elements during growing season of vegetable crops. The effect of slope on diurnal extreme temperatures in the vegetable cropped field conditions was more pronounced than that of elevation. Accordingly to developed maps, the warmest and longest duration of sunshine, and the least precipitation totals during growing season occurred in the middle part of Polabi.

Ginger consumption enhances the thermic effect of food and promotes feelings of satiety without affecting metabolic and hormonal parameters in overweight men: A pilot study

Science.gov (United States)

Mansour, Muhammad S.; Ni, Yu-Ming; Roberts, Amy L.; Kelleman, Michael; RoyChoudhury, Arindam; St-Onge, Marie-Pierre

2012-01-01

Objective Evidence suggests that ginger consumption has anti-inflammatory, anti-hypertensive, glucose-sensitizing, and stimulatory effects on the gastrointestinal tract. This study assessed the effects of a hot ginger beverage on energy expenditure, feelings of appetite and satiety and metabolic risk factors in overweight men. Methods Ten men, age 39.1 ± 3.3 y and body mass index (BMI) 27.2 ± 0.3 kg/m2, participated in this randomized crossover study. Resting state energy expenditure was measured using indirect calorimetry and for 6 h after consumption of a breakfast meal with or without 2 g ginger powder dissolved in a hot water beverage. Subjective feelings of satiety were assessed hourly using visual analog scales (VAS) and blood samples were taken fasted and for 3 h after breakfast consumption. Results There was no significant effect of ginger on total resting energy expenditure (P = 0.43) or respiratory quotient (P = 0.41). There was a significant effect of ginger on thermic effect of food (ginger vs control = 42.7 ± 21.4 kcal/d, P = 0.049) but the area under the curve was not different (P = 0.43). VAS ratings showed lower hunger (P = 0.002), lower prospective food intake (P = 0.004) and greater fullness (P = 0.064) with ginger consumption versus control. There were no effects of ginger on glucose, insulin, lipids, or inflammatory markers. Conclusions The results, showing enhanced thermogenesis and reduced feelings of hunger with ginger consumption, suggest a potential role of ginger in weight management. Additional studies are necessary to confirm these findings. PMID:22538118

SILOETTE, a training centre for reactor physics at the Nuclear Research Centre of Grenoble

International Nuclear Information System (INIS)

Destot, M.

1983-10-01

The Reactor Department of Grenoble has created, based on Siloette, an activity of training in reactor physics, wich is running since 1975 to meet the important needs generated by the development of electronuclear power stations. Its essential goal is to provide an initiation to the basic physical phenomena which determine the operation of the reactors. For that purpose, a rather comprehensive program of practical works on reactor (SILOETTE) and on nuclear power station simulators (PWR, UNGG) is proposed besides lectures and conferences, general and specialized teaching on the reactor operation principle, kinetics, dynamics and thermics

[Physiotherapy strategies in osteoporosis--recommendations for daily practice].

Science.gov (United States)

Uhlemann, C; Lange, U

2006-09-01

Physiotherapy in osteoporosis essentially takes the form of stimulatory therapy tailored to the findings and the pathomechanism. The choice of therapy and its dosage depend on the desired result (prevention, cure, rehabilitation). Physical therapy applied in osteoporosis includes electrical, thermic (hydrothermic, high frequency thermic, light thermic) and mechanical (massage, physiotherapy) stimuli, which can be applied regionally, locally or hoistically. To be efficient, a pain therapy requires that the various painful states be differentiated between: whereas, for example, in the case of acute pain physiotherapy fulfils the function of immediate therapy (normally rest and "mild" cold applications), in chronic pain it has to fulfil the function of an adaptive performance therapy of neuronal structures (formative-adaptive physiotherapy, thermic therapy improving trophism, direct current, transcutaneous electric nerve stimulation/TENS). It is necessary and extremely important forday-to-day clinical practice that physiotherapy strategies that are tailored to each patient's needs and also economically justifiable be implemented. The article isintended to contribute to this.

Radio-exposure tied to human activities other than medical uses of ionizing radiation, the functioning or nuclear power plants, or experimental atomic explosions

International Nuclear Information System (INIS)

Anon.

1990-01-01

The chapter deals only with the radio-exposure of the general public. Here the authors shall deal with the radio-exposure connected with the activities of two kinds of establishment: factories which prepare, manufacture, or transform radioactive substances, with the exception of nuclear power plants and their associated installations; and establishments which make use of techniques. The ever-expanding employment of radio-isotopes and radiation in industry is explained by the development of new applications and the increasing reliability of these materials. This technology presents many advantages. It allows one to economize on raw material as well as energy, to improve the quality of products while making these installations safer when functioning, and to protect the environment. The applications of radio-isotopes and radiation are varied, contributing to the efficiency of many industrial operations. The fundamental properties of the radio-elements are employed: the detectability over some distance of the radiations emitted by their chemical biological and thermic effects; and the identical behavior of different isotopes of the same element

Normothermic versus hypothermic cardiopulmonary bypass in children undergoing open heart surgery (thermic-2): study protocol for a randomized controlled trial.

Science.gov (United States)

Baos, Sarah; Sheehan, Karen; Culliford, Lucy; Pike, Katie; Ellis, Lucy; Parry, Andrew J; Stoica, Serban; Ghorbel, Mohamed T; Caputo, Massimo; Rogers, Chris A

2015-05-25

During open heart surgery, patients are connected to a heart-lung bypass machine that pumps blood around the body ("perfusion") while the heart is stopped. Typically the blood is cooled during this procedure ("hypothermia") and warmed to normal body temperature once the operation has been completed. The main rationale for "whole body cooling" is to protect organs such as the brain, kidneys, lungs, and heart from injury during bypass by reducing the body's metabolic rate and decreasing oxygen consumption. However, hypothermic perfusion also has disadvantages that can contribute toward an extended postoperative hospital stay. Research in adults and small randomized controlled trials in children suggest some benefits to keeping the blood at normal body temperature throughout surgery ("normothermia"). However, the two techniques have not been extensively compared in children. The Thermic-2 study will test the hypothesis that the whole body inflammatory response to the nonphysiological bypass and its detrimental effects on different organ functions may be attenuated by maintaining the body at 35°C-37°C (normothermic) rather than 28°C (hypothermic) during pediatric complex open heart surgery. This is a single-center, randomized controlled trial comparing the effectiveness and acceptability of normothermic versus hypothermic bypass in 141 children with congenital heart disease undergoing open heart surgery. Children having scheduled surgery to repair a heart defect not requiring deep hypothermic circulatory arrest represent the target study population. The co-primary clinical outcomes are duration of inotropic support, intubation time, and postoperative hospital stay. Secondary outcomes are in-hospital mortality and morbidity, blood loss and transfusion requirements, pre- and post-operative echocardiographic findings, routine blood gas and blood test results, renal function, cerebral function, regional oxygen saturation of blood in the cerebral cortex, assessment of

Contributions to the determination of the thermal core reliability of pressurized water reactors

International Nuclear Information System (INIS)

Ackermann, G.; Horche, W.; Melchior, H.; Prasser, H.M.

1982-09-01

The investigations in the field of thermohydraulics of PW reactors are aimed at a possible increase of economy and reliability of WWER-type-reactors. In detail the flow distribution at the core entrance, the modification of the power distribution as a result of an irregular temperature distribution at the core entrance, and based on the theory of hot spots the thermic core reliability are studied. In this connection qualitatively new methods are applied characterized by low expenditure. (author)

Thermically tuned nematic guide

Science.gov (United States)

Corella-Madueño, Adalberto; Reyes, Juan Adrián

2006-06-01

We consider a cylindrical fiber with a liquid crystal core satisfying homeotropic weak anchoring boundary conditions. We find the different textures of the nematic inside the cylinder obtained by changing the temperature. We calculate exactly the spatial distribution of the transverse magnetic modes in the guide as a function of temperature of the system by using a numerical scheme.

Investigation of solar parabolic trough power plants with and without integrated TES (thermal energy storage) and FBS (fuel backup system) using thermic oil and solar salt

International Nuclear Information System (INIS)

Boukelia, T.E.; Mecibah, M.S.; Kumar, B.N.; Reddy, K.S.

2015-01-01

Thermodynamic, economic and environmental analyses of concentrating solar power plants assist in identifying an effective and viable configuration. In this paper, a 4E (energy-exergy-environmental-economic) comparative study of 8 different configurations of parabolic trough solar thermal power plants with two different working fluids (Therminol VP-1 -oil and molten solar salt), with and without integrated thermal energy storage or/and backup fuel system is presented. The results of the comparative study indicate relevant differences among the 8 configurations. The molten solar salt configuration with integrated thermal energy storage and fossil fuel backup system exhibits the highest overall energy efficiency (18.48%) compared to other configurations. Whereas, the highest overall exergy efficiency (21.77%), capacity factor (38.20%) and annual energy generation (114 GWh) are found for the oil based configuration with integrated thermal energy storage and fossil fuel backup system. The results indicate that the configurations based on molten salt are better in terms of environmental and economical parameters. The configurations with integrated thermal energy storage and fossil fuel backup system are found to be techno-economical, but on the other hand are less environment friendly. A detailed comparison of these plants after optimization must be performed before drawing a final conclusion about the best configuration to be adopted in parabolic trough solar thermal power plant. - Highlights: • 4E comparative study of 8 configurations of PTSTPP with two different fluids. • Comparison of the configurations with and without integrated TES (thermal energy storage) and FBS (fuel backup system). • The overall energy efficiency of the salt plant with TES and FBS is the highest. • The overall exergy efficiency of the oil plant with TES and FBS is the highest. • The salt plants are the best configurations in terms of environ–eco parameters

Reference Book for the Nitrogen Industry Worker. Volume II,

Science.gov (United States)

1982-03-19

510 NO-- ......... p ., Figure 111-27. Nomogram to 8__ ao,( ’S O ’ Determine Coefficient C (for . ,ma )l isooc Calculation of Power of Iso -. . T2...CALCULATION OF ISO - THERMIC POWER IN COMPRESSION OF CERTAIN GASES 10 1 20 1 H30 1b4 0 1 20 30 4030- 0ol i ’ 10 ’ ’ 1 Bozopo4 (6)A oT 50 +0k13 +0.013...2230 1950 2187 597 1745 A02-92-2 2960 too Not designed for 2120 160 1330 597 90 working in air A-40-2 2955 160 12000- 27001 120 12996 1685 4 18 980

Effects of exposure to electromagnetic fields (microwaves) on mammalian pregnancy

International Nuclear Information System (INIS)

Dugauquier, C.

2006-01-01

Women soldiers account now for nearly 10 % of the NATO forces. Some studies have alleged that exposure to microwaves may result in pregnancy mishaps. We have tried to assess what was the risk. A lot of studies were conducted on non mammalian species: birds, sea urchins, worms and insects. Extrapolation to the mammals is subject to caution due to the protective effect of intrauterine development. We reviewed the literature dealing only with mammals. Even if some discrepancy persists, it seems that the presence or the absence of thermic effect is essential in order to estimate the risk. Reduced birth weight and increased rate of miscarriage were the most common findings when the exposure reached a thermic effect. In the majority of the studies, non thermic exposure had no impact on pregnancy outcome. (authors)

Effects of exposure to electromagnetic fields (microwaves) on mammalian pregnancy; Effets sur la gestation des mammiferes de l'exposition aux champs electromagnetiques (micro-ondes)

Energy Technology Data Exchange (ETDEWEB)

Dugauquier, C. [Hopital Central de la Base Reine Astrid, Div. Epidemiologie et Biostatistiques, Bruxelles (Belgium)

2006-06-15

Women soldiers account now for nearly 10 % of the NATO forces. Some studies have alleged that exposure to microwaves may result in pregnancy mishaps. We have tried to assess what was the risk. A lot of studies were conducted on non mammalian species: birds, sea urchins, worms and insects. Extrapolation to the mammals is subject to caution due to the protective effect of intrauterine development. We reviewed the literature dealing only with mammals. Even if some discrepancy persists, it seems that the presence or the absence of thermic effect is essential in order to estimate the risk. Reduced birth weight and increased rate of miscarriage were the most common findings when the exposure reached a thermic effect. In the majority of the studies, non thermic exposure had no impact on pregnancy outcome. (authors)

Thermal calculations for water cooled research reactors

International Nuclear Information System (INIS)

Fabrega, S.

1979-01-01

The formulae and the more important numerical data necessary for thermic calculations on the core of a research reactor, cooled with low pressure water, are presented. Most of the problems met by the designer and the operator are dealt with (calculations margins, cooling after shut-down). Particular cases are considered (gas release, rough walls, asymmetric cooling slabs etc.), which are not generally envisaged in works on general thermics

Sensible biological models to be exposed to VDT (Video Display Terminal) radiations in human male reproduction

International Nuclear Information System (INIS)

Tritto, J.; North, M.-O.; Laverdure, A.M.; Surbeck, J.

1999-01-01

Temperature and environmental effects, particularly endocrine disrupters and EMF radiations, are actively investigated in human and non-human reproduction experimental models. Sensitivity and specificity of the different cell types of the testes seminiferous tubules in animals and in human are evaluated, showing a specific responsiveness of spermatogonia (SPG) and resting pachytene spermatocytes (SPC). At 32 o C the 24 h short-term cultures of biopsies of normal human testis show an expected low occurrence of apoptotic SPG (1 %) that increases to 3,4 % in peer samples exposed to VDT for the same period, with the appearance of apoptotic SPC (4,6 %). In samples from a thermically-impaired testis of the same subject the apoptotic occurrence of SPG is 2,6 % with 15,4 % for SPC after 24 h cultures. After 24 h exposure to VDT the apoptotic score is 7,6 % for SPG and 18,5 % for SPC in thermically impaired peer samples. With EMF-bioshields the apoptotic score for SPG is 0,8 % in normal 2,2 % for SPG and 13,8 % for SPC in T-impaired peer-samples. NMRS of the cultures fluids show a proportional production of lactate, corresponding to the different degrees of histopathological impairment of the samples. IVOS (Integrated Visual Optic System) analysis of sperm samples from thermically-impaired, not-repaired and repaired testes exposed to VDT shows sensible variations on straightness (STR), linearity (LIN) and lateral head displacement (LHD) parameters. To evaluate the thermic and non-thermic potential bioeffects of VDT on human spermatogenesis the specificity, the sensitivity and the reproducibility of the biological models on one side and the specificity of the methodologies on the other side must be provided. (author)

Weight Management, Energy Metabolism, and Endocrine Hor¬mones- Review Article

OpenAIRE

Seyed-Ali MOSTAFAVI; Saeed HOSSEINI

2015-01-01

Energy expenditure is determined by basal metabolic rate, physical activity, and Thermic Effect of Foods (TEF). Some endocrine hormones have role in basal metabolism and hence in human energy expenditure. And some foods pose more thermic effects on the total body energy expenditure and therefore can influence body weight. This review was performed to discuss factors which may affect body metabolism and body weight. Latest medical databases and nutrition and metabolism books were reviewed. We ...

The application of calorimetrical methods in nuclear technology and dosimetry

International Nuclear Information System (INIS)

Kott, J.; Krett, V.; Novotny, J.; Kovar, Z.; Jirousek, V.

1985-01-01

The report reviews theoretical as well as experimental research activities devoted to the possibilities of measuring reactor neutron and photon fields using thermic detectors based on calorimetric principle. There have been worked out theoretical principles of a reactor measuring probe intended in the first place to measuring neutron fluxes under operational temperatures inside power and research reactors, and a new philosophy of measurement has been elaborated. In addition, the report presents the experimental results as obtained on research reactors WWR-S, WWR-SM, RA, and Czechoslovak power reactor A-1 and GDR power reactor WWR-2. These results are given in connection with a newly proposed technique of reactor neutron field detection. The second part of the report presents results of works concerning beam dosimetry with the use of calorimeters

Impaired glucose-induced thermogenesis and arterial norepinephrine response persist after weight reduction in obese humans

DEFF Research Database (Denmark)

Astrup, A; Andersen, T; Christensen, N J

1990-01-01

A reduced thermic response and an impaired activation of the sympathetic nervous system (SNS) has been reported after oral glucose in human obesity. It is, however, not known whether the reduced SNS activity returns to normal along with weight reduction. The thermic effect of glucose was lower...... in eight obese patients than in matched control subjects (1.7% vs 9.2%, p less than 0.002). The increase in arterial norepinephrine after glucose was also blunted in the obese patients. After a 30-kg weight loss their glucose and lipid profiles were markedly improved but the thermic effect of glucose...... was still lower than that of the control subjects (4.2%, p less than 0.001). The glucose-induced arterial norepinephrine response remained diminished in the reduced obese patients whereas the changes in plasma epinephrine were similar in all three groups. The results suggest that a defective SNS may...

Long-distance heat transport by hot water

International Nuclear Information System (INIS)

Munser, H.; Reetz, B.

1990-01-01

From the analysis of the centralized heat supply in the GDR energy-economical and ecological indispensable developments of long-distance heat systems in conurbation are derived. The heat extraction from a nuclear power plant combined with long- distance hot-water transport over about 110 kilometres is investigated and presented as a possibility to perspective base load heat demands for the district around Dresden. By help of industrial-economic, hydraulic and thermic evaluations of first design variants of the transit system the acceptance of this ecologic and energetic preferred solution is proved and requirements for its realization are shown

Radiobiological assessment of usability of the fly ash from coal-fired power plants in building sector in Turkey

International Nuclear Information System (INIS)

2009-01-01

In this study, the specific activities of 2 26Ra, 2 32Th and 4 0K radionuclide in the samples of cement and concrete added fly ash (FA) used building sector were measured by using gamma spectrometer with HPGe detector. In order to assess the usability of the samples of the cement and concrete added FA in building sector and the FA samples obtained as a by-product from coal-burning thermic power plants in Turkey in geotechnical applications from radiological point of view, the radium equivalent activity (Ra e q), the activity concentration index (Iγ), the alpha index (Iα), the absorbed gamma dose rates (D I O, D D O) and the corresponding effective dose rates (H I O, H D O) caused from the external exposure in indoor and outdoor were calculated and compared with the limit value or the criterion. The results showed that the mean values of the Ra e q, Iγ (except the mean value calculated for the concrete added with 30% Kangal FA), Iα (except the mean values calculated for the cement added with 30-35%) and the indoor effective dose rate (except the mean values calculated for the cement added with 30-35% and the concrete added with 30% Kangal FA) were lower than or close to the limit value or the criterion recommended for the safe use of construction materials. (Includes 12 figures and 12 tables)

CARS measurement of vibrational and rotational temperature with high power laser and high speed visualization of total radiation behind hypervelocity shock waves of 5-7km/s

Science.gov (United States)

Sakurai, Kotaro; Bindu, Venigalla Hima; Niinomi, Shota; Ota, Masanori; Maeno, Kazuo

2010-09-01

Coherent Anti-Stokes Raman Spectroscopy (CARS) method is commonly used for measuring molecular structure or condition. In the aerospace technology, this method is applies to measure the temperature in thermic fluid with relatively long time duration of millisecond or sub millisecond. On the other hand, vibrational/rotational temperatures behind hypervelocity shock wave are important for heat-shield design in phase of reentry flight. The non-equilibrium flow with radiative heating from strongly shocked air ahead of the vehicles plays an important role on the heat flux to the wall surface structure as well as convective heating. In this paper CARS method is applied to measure the vibrational/rotational temperature of N2 behind hypervelocity shock wave. The strong shock wave in front of the reentering space vehicles can be experimentally realigned by free-piston, double-diaphragm shock tube with low density test gas. However CARS measurement is difficult for our experiment. Our measurement needs very short pulse which order of nanosecond and high power laser for CARS method. It is due to our measurement object is the momentary phenomena which velocity is 7km/s. In addition the observation section is low density test gas, and there is the strong background light behind the shock wave. So we employ the CARS method with high power, order of 1J/pulse, and very short pulse (10ns) laser. By using this laser the CARS signal can be acquired even in the strong radiation area. Also we simultaneously try to use the CCD camera to obtain total radiation with CARS method.

Análisis de la operación del horno alto mediante la exergía térmica

Directory of Open Access Journals (Sweden)

Babich, A.

1998-05-01

Full Text Available In order to know the blast furnace thermic state, the thermic exergy can be used, which considers the temperatures level of the process. The magnitude analysis of thermic exergy for blast furnace operation using pulverized coal, natural gas and oxigen injection by tuyeres, shows that natural gas injection is less effective than pulverized coal and enriched blast with oxygen simultaneous injection.

Para conocer el estado térmico del horno alto se puede utilizar la exergía térmica, que considera el nivel de temperaturas del proceso. El análisis de la magnitud de la exergía térmica, para la operación del horno alto, utilizando inyecciones por toberas de carbón pulverizado, de gas natural y viento enriquecido en oxígeno, en ambos casos muestra que la inyección de gas natural es menos efectiva que la inyección simultánea de carbón pulverizado y viento enriquecido con oxígeno.

ELECTRODE SELECTION FOR RECOVERY OF THE CYLINDER LIDS OF THE TGM8K LOCOMITIVE ENGINE

Directory of Open Access Journals (Sweden)

Pablo Oñoz Gutiérrez

2017-01-01

Full Text Available The objective of this work was to determine the best-suited electrode to carry out the recovery of cylinder lids (cylinders heads of the TGM8K locomotives, by applying manual welding for electric arc. The test specimens of nodular cast iron, obtained from a discarded head, which were welded with two types electrodes, ENi-CI (UTP8 and ENiFe-CI ( UTP86FN following a technology of appropriate welding were prepared. The specimens were subject of thermic fatigue tests in an experimental installation created with this purpose, in which a process of heating and more severe cooling than in the head working conditions was simulated. During the thermic fatigue tests, in the specimens welded with electrodes ENi-CI appeared cracks at the thermic influence zone after 145 cycles, while in the specimens welded with electrodes ENiFe-CI, appeared at the 585 cycles on average. Based on the study results, the authors conclude that ENiFe-CI electrodes are the best-suited for the recovery of the cylinder lids.

Process and installation for heat recovery. Verfahren und Anlage zur Waermerueckgewinnung

Energy Technology Data Exchange (ETDEWEB)

Zeller, M.

1990-01-10

The patent describes a method for heat recovery from the warmer of two separately conducted streams of a fluid, whereby heat is recovered through a first heat exchanger in the warmer stream of medium, a heat transfer medium in a transmitting circuit and a second heat exchanger in the cooler stream of fluid, whereby the transmitting circuit includes both heat exchangers, characterized in that the recovered thermic output ({Delta}t.Q) is continuously detected and a regulation of the quantity (Q) of heat transfer medium in this circuit to maximum thermic output is effected. (author) 4 figs., 2 refs.

Influence of temperature in TL signal induced by gamma radiation in zircon prepared by sol gel via

International Nuclear Information System (INIS)

Salas, P.; Castano, V.M.; Mendoza A, D.; Gonzalez M, P.R.; Rosa C, E. de la

2000-01-01

In this work, it was realized a study of the temperature effects in thermoluminescent signal (Tl) induced by gamma radiation in zircon, which was prepared by the sol gel method. According to the obtained results, the zircon thermically treated at 500 C or over is sensitive to radiation. This sensitivity is increased when the temperature in study is augmented, moreover, the Tl spectra form also is modified with the temperature increment. The samples thermically treated at 750 C or over present a linear response in the dose interval 27 to 165 Gy; therefore, such materials result promissories for dosimetric purposes. (Author)

Influence of temperature in TL signal induced by gamma radiation in zircon prepared by sol gel via; Influencia de la temperatura en la senal TL inducida por la radiacion gamma en zirconia preparada via solgel

Energy Technology Data Exchange (ETDEWEB)

Salas, P.; Castano, V.M. [Instituto de Fisica, UNAM, Laboratorio Juriquilla, A.P. 1-1010, 76001 Queretaro (Mexico); Mendoza A, D.; Gonzalez M, P.R. [ININ, Mexico, D.F. (Mexico); Rosa C, E. de la [Centro de Investigaciones en Optical, Leon, Gto. (Mexico)

2000-07-01

In this work, it was realized a study of the temperature effects in thermoluminescent signal (Tl) induced by gamma radiation in zircon, which was prepared by the sol gel method. According to the obtained results, the zircon thermically treated at 500 C or over is sensitive to radiation. This sensitivity is increased when the temperature in study is augmented, moreover, the Tl spectra form also is modified with the temperature increment. The samples thermically treated at 750 C or over present a linear response in the dose interval 27 to 165 Gy; therefore, such materials result promissories for dosimetric purposes. (Author)

Biogas recovery from tanning sludges. Anaerobic digestion of lime fleshings, tanning sludge, and unhairing baths, laboratory and pilot scale results

Energy Technology Data Exchange (ETDEWEB)

Fendrup, W.; Hansen, S.; Petersen, G.

1983-11-01

Mesophilic anaerobic digestion of various types of tannery and other wastes, separately or in mixtures, has been investigated. The following materials were used: Lime fleshings, Tannery sludge, Beamhouse sludge, Municipal sludge, Chrome leather shavings, Liquid manure. The investigations have shown anaerobic digestion to be possible with untanned tannery wastes as well as tannery effluent sludge as a substrate. Specially high gas yields were found by digestion of mixtures of tannery wastes and manure. This may be applicable to mixtures of tannery wastes and municipal sludge, too. The gas contains 0.5 - 1.0% H2S. About 25% of the gross energy (methane) output is used for sustaining the temperature necessary for the digestion together with the mixing and conveying of the material to be digested. If electricity is produced, 25% of the gross output is obtained as useful electric energy and 35% as useful thermic energy. If the gas is burned, 60% of the gross output is obtained as useful thermic energy. With the price relations found in most countries (e.g. Denmark, Finland and Sweden) it will be most profitable to produce electricity, whereas in some cases (e.g. Norway) the opposite may be true. The energy requirement of a typic Scandinavian tannery is 14.200 MJ/t rawhide as thermic energy and 2.300 MJ/t rawhide as electric energy, which means that maximum 14% of the thermic energy requirement or maximum 35% of the electricity requirement could be covered by the wastes digestion. Profitability calculations are made for each Scandinavian country. The calculations show that too small digestion plants are not profitable.

Study of wine-growing land ('terroirs') characteristics in the canton of Vaud (Switzerland): modelization of the climatical parameters

International Nuclear Information System (INIS)

Pythoud, K.

2004-01-01

As part of a study on the viticultural terroirs of 'canton de Vaud', a climatic model integrating temperature, relief, radiation and pluviometry was built. The climate is defined by pluviometry and the thermical gradient. For standard needs, climatic parameters are determined at small scale (b 1/300'000), which is not accurate for the study of the mesoclimate. The adopted approach uses a digital elevation model with a resolution of 25 meters, the DEM25 of the Swiss Federal Office of Topography, at 1/25'000 scale. The thermical gradient is deduced from solar radiation, wind effect estimations and an empirical model of thermical altitudinal distribution. The radiation is calculated with a model that integrates the effects of the surrounding relief (slope, exposition and casted shadow) and the sun height above the horizon during a specific period. The relief shape and the principal wind directions based on a regional cartography allowed to estimate wind effect. Then climatic parameters are calculated for critical periods in the vineyard's vegetative cycle. A comparison with the map of thermical levels of 'canton de Vaud', determined on the basis of a phenological survey, allows to adjust the microclimate model. The rainfall distribution is the result of a data regionalization coming from Meteoswiss stations network. The calculation was based on the monthly rainfall values collected in the stations near or inside the vineyard during the last 30 years. The final climatic zoning is a weighting of the previous mentioned variables. Its value is more qualitative than quantitative. It offers however a comparison basis between the different regions concerned by the study

Epinephrine mediates facultative carbohydrate-induced thermogenesis in human skeletal muscle

DEFF Research Database (Denmark)

Astrup, A; Simonsen, L; Bülow, J

1989-01-01

The thermic effect of carbohydrate has a component mediated by the sympathoadrenal system but of unknown anatomical localization. We have studied the contribution of skeletal muscle to the thermic effect of a carbohydrate-rich natural meal (115 g of carbohydrate, approximately 80% of energy...... postprandially and coinciding with the peak in arterial epinephrine. The present study provides evidence of a facultative thermogenic component in skeletal muscle, mediated by epinephrine via beta 2-adrenoreceptors. However, it also points to a nonmuscle component mediated through beta 1-adrenoceptors...... by norepinephrine released from the sympathetic nervous system. Consequently, the sympathoadrenal system seems to play a physiological role in the daily energy balance....

Scenarios for the hierarchical evaluation of the global sustainability of electric generator plants

International Nuclear Information System (INIS)

Roldan A, M.C.; Martinez F, M.

2007-01-01

The AHP multi criteria method was applied (Analytic Hierarchy Process-Analytic process of Hierarchization) to evaluate the sustainability in the whole life cycle of the electricity generation technologies (hydroelectric, carboelectric, thermoelectric natural fuel oil, natural gas thermoelectric, geothermal, nucleo electric, wind electric, photo thermic and photovoltaic) with the purpose of offering an useful method in the taking of decisions to impel the sustainable development. Eight scenarios are analyzed. The results in most of the scenarios reflect the benefit of the renewable energy: the hydroelectric energy, photo thermic and wind driven its are those more sustainable. To reach the sustainable development in Mexico, the energy politicians should be more near to the use of the renewable energy. (Author)

Scenarios for the hierarchical evaluation of the global sustainability of electric generator plants; Escenarios para la evaluacion jerarquica de la sustentabilidad global de plantas generadoras de electricidad

Energy Technology Data Exchange (ETDEWEB)

Roldan A, M.C.; Martinez F, M. [Centro de Investigacion en Energia, UNAM, A.P. 34, 62580 Temixco, Morelos (Mexico)]. e-mail: mcra@cie.unam.mx

2007-07-01

The AHP multi criteria method was applied (Analytic Hierarchy Process-Analytic process of Hierarchization) to evaluate the sustainability in the whole life cycle of the electricity generation technologies (hydroelectric, carboelectric, thermoelectric natural fuel oil, natural gas thermoelectric, geothermal, nucleo electric, wind electric, photo thermic and photovoltaic) with the purpose of offering an useful method in the taking of decisions to impel the sustainable development. Eight scenarios are analyzed. The results in most of the scenarios reflect the benefit of the renewable energy: the hydroelectric energy, photo thermic and wind driven its are those more sustainable. To reach the sustainable development in Mexico, the energy politicians should be more near to the use of the renewable energy. (Author)

Viability study for application of combined reheater cycle (CRC) to fluidized bed combustion plants; Estudio de Viabilidad para la Aplicacion del Ciclo de Recalentamiento Combinado (CRC) a Plantas de Combustion de Lecho Fuido Atmosferico

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-12-01

Basically, the project try to analyze the application viability of a first reheating in steam cycles of little power plants, useful mainly for biomass and wastes, in our case with coal blends; and a second reheating of the steam in conventional and fluidized bed combustion plants. Using in both cases the thermic energy of the exhaust gases from one gas turbine. The advantages of the CRC cycle are: (1) Reduction of the moisture in the turbine, increasing the energy efficiency and blade protection. (2) To take advantage of the waste gas energy from the gas turbine in optimum way. (3) Great operation flexibility under good efficiency results. In general, the system can use the synergy between gas, coal and waste energies with the highest global efficiency. (Author)

Study of the variation of the nuclear transcriptional map during de initial development of Drosophyla melanogaster embryos

International Nuclear Information System (INIS)

Alonso, C.E.V.

1987-01-01

The variation of nuclear transcriptional map during the initial development of Drosophyla melanogaster embryos were studied. Thermic treatment, chromatographic techniques and liquid scintilation in embryos inoculated with radioactive uridine were used. (L.J.C.)

Science and technology of the rare earth elements

International Nuclear Information System (INIS)

Azzouz, Abdelkrim; Chegrouche, Salah; Telmoune, Sid-Ali; Layachi, Lazhar

1992-07-01

The present work studies the chemical physics properties, the different methods of analysis (neutron activation, emission spectrometry, chromatography), and the techniques of separation of rare earth (electrodeposition, thermic decomposition, salts distillation and ions exchange)

Application of fluorides as reagents in exothermal reducing processes

International Nuclear Information System (INIS)

Solov'ev, A.I.; Maksimov, Yu.M.; Dedov, N.V.; Malyutina, V.M.; Avramchik, A.N.

2002-01-01

Thermodynamic calculations were made and the process of calcium-thermic reduction of titanium and zirconium tetrafluorides and their mixtures was experimentally studied. Compound TiF 4 and its mixture with ZrF 4 in amount no more than 34.3 % are reduced producing a well-formed ingot. When ZrF 4 content is exceeded in the mixture to be reduced as well as during reduction of pure ZrF 4 and the mixture of unseparated rare earth metal fluorides, metal and alloys are produced as embedded particles in solidified slag. Additional heat should be brought to produce qualitative ingot during the reducing process. Qualitative ingots of metal in weight up to 10 kg were produced during calcium-thermic reduction of zirconium and rare earth fluorides with application of high-frequency induction heating [ru

Determination of the minimum number of fuel elements of the RP-10 research reactor

International Nuclear Information System (INIS)

Languasco, J.

1989-01-01

The peruvian research reactor RP-10 is composed of a compound nucleus of boxes containing fuel plates which are cooled with light water in order to remove heat produced by fission of uranium atoms. However from a certainty viewpoint, it exists certain restrictions to design the cooling system. The most admissible caloric flux of 90.3 watts/cm 2 is deflux of 90.3 watts/cm 2 is determined on the basis of these thermic restrictions when cooling speed is 409 cm/sec permitting at least 24 fuel elements(boxes) within the nucleus. On the basis of restrictions of load loss in the nucleus, it would be permitted at least 18 fuel elements, but this quantity breaks thermic restrictions for this reason, 24 boxes in the nucleus will be the minimum number of elements

World energy 2007: an increase of consumptions in spite of the flight of prices

International Nuclear Information System (INIS)

Martin-Amouroux, J.M.

2008-01-01

At the end of the year 2007, the energy prices have continued to increase. Compared with 2006 (2.4%), the world primary consumption has increased (2.8%), as well as those of the electric power: (3.7%) to (4.5%), whereas the GDP (gross domestic product) has not changed. The emergent economies have still taken the greatest part of this growth, but for them, as for the OECD member countries, the year 2007 presents some particularities. The North America is hard at restraining the increase of its consumption. Asia, is always at the first place of the emergent economies but is not alone. The flame thermics is gaining ground in the world electric production. Between the fossil fuels, coal is gaining gas and still more petroleum. Concerning CO 2 , the increase is continuing. (O.M.)

Forecast situation of the blast furnace cohesive zone; Situacion estimada de la zona cohesiva en el horno alto

Energy Technology Data Exchange (ETDEWEB)

Cores, A.; Saiz de Ayala, J.; Mochon, J.; Ruiz-Bustinza, I.; Parra, R.

2010-07-01

A series of sinters are manufactured in the pilot plant, using a mineral mixture, like that blast furnace. The sinters are characterised, by chemical and granulometric analysis and by determining the softening and melting temperatures. In the blast furnace temperatures are determined by using a series of probes in the furnace which make it possible to locate the position of the isotherm of higher temperature of 950 degree centigrade, which correspond to the reserve thermic zone. A model has been developed, proposing and indirect estimation of the shape of the cohesive zone through the determination of the isotherm with the highest temperature in the thermic reserve zone. The values of the softening and melting temperatures of sinters can be used to estimate the isotherms limiting the cohesive zone in the 1300-1400 degree centigrade range. (Author)

The microstructure and coefficient transmission of think films Bi2Te3-xSex, alloyed by terbium

International Nuclear Information System (INIS)

Abdullaev, N.M.; Mekhtieva, S.I.; Jalilov, N.Z.; Memmedov, N.R.; Zeynalov, V.Z.

2007-01-01

The defects of films microstructures of the thermoelectric materials n- and p-type Bi 2 Te 3 -xSe x , alloyed by Tb and Cl, with think, obtained by thermic evaporation in vacuum have been investigated by microscopic methods

Complete automation of nuclear reactors control

International Nuclear Information System (INIS)

Weill, J.

1955-01-01

The use of nuclear reactor for energy production induces the installation of automatic control systems which need to be safe enough and can adapt to the industrial scale of energy production. These automatic control systems have to insure the constancy of power level and adjust the power produced to the energy demand. Two functioning modes are considered: nuclear plant connected up to other electric production systems as hydraulic or thermic plants or nuclear plants functioning on an independent network. For nuclear plants connected up with other production plants, xenon poisoning and operating cost lead to keep working at maximum power the nuclear reactors. Thus, the power modulation control system will not be considered and only start-up control, safety control, and control systems will be automated. For nuclear power plants working on an independent network, the power modulation control system is needed to economize fuel. It described the automated control system for reactors functioning with constant power: a power measurement system constituted of an ionization chamber and a direct-current amplifier will control the steadfastness of the power produced. For reactors functioning with variable power, the automated power control system will allow to change the power and maintain it steady with all the necessary safety and will control that working conditions under P max and R max (maximum power and maximum reactivity). The effects of temperature and xenon poisoning will also be discussed. Safety systems will be added to stop completely the functioning of the reactor if P max is reached. (M.P.)

Complete automation of nuclear reactors control; Automatisation complete de la conduite des reacteurs nucleaires

Energy Technology Data Exchange (ETDEWEB)

Weill, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

The use of nuclear reactor for energy production induces the installation of automatic control systems which need to be safe enough and can adapt to the industrial scale of energy production. These automatic control systems have to insure the constancy of power level and adjust the power produced to the energy demand. Two functioning modes are considered: nuclear plant connected up to other electric production systems as hydraulic or thermic plants or nuclear plants functioning on an independent network. For nuclear plants connected up with other production plants, xenon poisoning and operating cost lead to keep working at maximum power the nuclear reactors. Thus, the power modulation control system will not be considered and only start-up control, safety control, and control systems will be automated. For nuclear power plants working on an independent network, the power modulation control system is needed to economize fuel. It described the automated control system for reactors functioning with constant power: a power measurement system constituted of an ionization chamber and a direct-current amplifier will control the steadfastness of the power produced. For reactors functioning with variable power, the automated power control system will allow to change the power and maintain it steady with all the necessary safety and will control that working conditions under P{sub max} and R{sub max} (maximum power and maximum reactivity). The effects of temperature and xenon poisoning will also be discussed. Safety systems will be added to stop completely the functioning of the reactor if P{sub max} is reached. (M.P.)

Relationship between osmotic pressure of the blood and secretion of sweat

Science.gov (United States)

Montuori, A.

1978-01-01

Experiments with cats show that the thermic secretion of sweat represents a specific case of a general law: The central nervous apparatus that controls the secretion of sweat begins to function when the osmotic pressure of the blood drops below normal.

Study of the national electricity system equipment until the year 2000

International Nuclear Information System (INIS)

1980-01-01

This work is about a study by UTE and German consultants. It is to ensure the supply of electricity in times of unfavorable hydrogeological conditions. In this case is necessary to install new thermic units or import energy from neighboring countries

Detection of plastic explosives by thermic neutron radiography

International Nuclear Information System (INIS)

Hacidume, Leo R.; Crispim, Verginia R.; Silva, Ademir X. da

2000-01-01

This work aims to demonstrate the potentiality of the neutron radiography technique, allied to the computerized tomography by transmission, to both detect and visualize plastic explosive samples in several hidden conditions, using a simple scanner as a digitalisation instrument. Each tomographic essay was obtained in the J-9 channel of the Argonauta Research Reactor of IEN/CNEN, in groups of six neutron radiographic projections, performed with an angular increment of 30 in a period of time of 30 minutes for each projection. Two groups of tomographic reconstructions were generated, distinguished by the digitalisation process of the interested lines in the reconstruction plane coming from the projection groups, utilizing a scanner and a microdensitometer, respectively. The reconstruction of the bi-dimensional image of the transverse section, in relation to this plane, was processed making use of the Image reconstruction algorithmic of an image based on the maximum entropy principle (ARIEM). From the qualitative analysis of the images, we conclude that the neutron radiographic system was able to detect the explosive sample in a satisfactory way while the quantitative analysis confirmed the application effectiveness of a scanner to acquire the projection dates whose objective is only a reconnaissance. (author)

Thermic decomposition of biphenyl; Decomposition thermique du biphenyle

Energy Technology Data Exchange (ETDEWEB)

Lutz, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1966-03-01

Liquid and vapour phase pyrolysis of very pure biphenyl obtained by methods described in the text was carried out at 400 C in sealed ampoules, the fraction transformed being always less than 0.1 per cent. The main products were hydrogen, benzene, terphenyls, and a deposit of polyphenyls strongly adhering to the walls. Small quantities of the lower aliphatic hydrocarbons were also found. The variation of the yields of these products with a) the pyrolysis time, b) the state (gas or liquid) of the biphenyl, and c) the pressure of the vapour was measured. Varying the area and nature of the walls showed that in the absence of a liquid phase, the pyrolytic decomposition takes place in the adsorbed layer, and that metallic walls promote the reaction more actively than do those of glass (pyrex or silica). A mechanism is proposed to explain the results pertaining to this decomposition in the adsorbed phase. The adsorption seems to obey a Langmuir isotherm, and the chemical act which determines the overall rate of decomposition is unimolecular. (author) [French] Du biphenyle tres pur, dont la purification est decrite, est pyrolyse a 400 C en phase vapeur et en phase liquide dans des ampoules scellees sous vide, a des taux de decomposition n'ayant jamais depasse 0,1 pour cent. Les produits provenant de la pyrolyse sont essentiellement: l' hydrogene, le benzene, les therphenyles, et un depot de polyphenyles adherant fortement aux parois. En plus il se forme de faibles quantites d'hydrocarbures aliphatiques gazeux. On indique la variation des rendements des differents produits avec la duree de pyrolyse, l'etat gazeux ou liquide du biphenyle, et la pression de la vapeur. Variant la superficie et la nature des parois, on montre qu'en absence de liquide la pyrolyse se fait en phase adsorbee. La pyrolyse est plus active au contact de parois metalliques que de celles de verres (pyrex ou silice). A partir des resultats experimentaux un mecanisme de degradation du biphenyle en phase adsorbee est suggere, l'adsorption paraissant regie par l'isotherme de Langmuir, et l'acte chimique determinant la vitesse globale de la pyrolyse etant monomoleculaire en ce qui concerne le molecule de biphenyle adsorbee. (auteur)

[Effects of sterilization and disinfection on mechanical properties of Sentalloy springs].

Science.gov (United States)

Maddalone, M; Amalto, L; Cocconi, R; Ciafone, E

1991-01-01

The Authors evaluated mechanic characteristics of open and close titanium coils after two cycles of simulated usage. Coils undergone to thermic autoclaving didn't show any substantial variation in the forces offered compared to those only disinfected, authorizing reusage with igienic guarantees.

Study of viability on the destruction of weed seeds in the soil by microwave radiation

International Nuclear Information System (INIS)

Velazquez-Marti, B.; Osca, J.M.; Jorda, C.; Marzal, A.

2003-01-01

This work has been carried out to study the thermic effects over weed seeds in typical orchard soil irradiated by its surface with microwave. A previous treatment was carried out in a domestic microwave oven, using 660-watt power. With this laboratory oven, we have investigated three kind of weed seeds: Lolium perenne, Sinopsis alba and Setaria sativa. These previous experiments showed a important decrease of germination with short irradiating times. After previous treatment, a microwave applicator, designed to achieve wide distribution of superficial irradiation energy, was evaluated. This applicator is powered by a 4-kilowatt magnetron through a slotted waveguide. With this oven, we have investigated two kind of weed seeds at several depths: Lolium perenne and Brassica napus var. oleifera. For a soil column, temperature increments reduce seeds germination to a maximum of 5 centimetres. Deeper, the increments of temperature are very low for short irradiating times, so it will be negligible for our purpose. This applicator lets approach better to real treatments focused into the development of a continuous microwave oven for disinfecting seedbed and greenhouse crop substratum. (author) [es

ASPECTS REGARDING THE ELECTROTHERMAL HEATING THROUGH ELECTROMAGNETIC INDUCTION

Directory of Open Access Journals (Sweden)

Teodor LEUCA

2009-05-01

Full Text Available The paper present the numerical modeling of the electromagnetic phenomena coupled with the thermic ones when processing the semi-finished products made up of non-ferrous alloy, through electromagnetic induction with the purpose to obtain a homogenous heating of the pieces in the shortest time. Maxwell’s equations that describe the heating process through induction, show that the important quantity, basically important to determine the eddy currents induced in the piece, is the intensity of the magnetic field, resulting the electromagnetic losses, due to their transformation in thermic energy. So far the results of the experiments have show that the intensity of the magnetic field considering a long inductor is more intense in the center of the inductor and weaker at its extremes. The purpose of the numerical modeling is to render solution to homogenize the intensity of the magnetic field according to the geometry of the inductor.

Resting metabolic rate and postprandial thermogenesis in polycystic ovarian syndrome.

Science.gov (United States)

Segal, K R; Dunaif, A

1990-07-01

To determine whether the high frequency of obesity in women with polycystic ovary syndrome (PCO) is related to a defect in energy expenditure, resting metabolic rate (RMR) and the thermic response to a standard meal were compared in 10 obese PCO women, nine obese but otherwise normal women, and 11 lean women. All groups were matched with respect to age and fat-free mass and the two obese groups were matched for degree of obesity. RMR was measured by indirect calorimetry for 3 h on two days: (1) in the postabsorptive state; and (2) after a 720 kcal (3014 kJ) liquid mixed meal. The thermic effect of food, calculated as 3 h postprandial minus fasting RMR, was significantly greater for the lean [52.9 +/- 5.5 kcal/3 h (221 +/- 23 kJ/3 h)] than the obese [17.2 +/- 5.1 kcal/3 h (72 +/- 21 kJ/3 h)] and the PCO women [22.8 +/- 5.2 kcal/3 h (95 +/- 22 kJ/3)], P less than 0.001). The thermic effect of food was negatively related to percent body fat (r = -0.694, P less than 0.001). Resting metabolic rate did not differ significantly among the three groups, and was strongly related to fat-free mass (r = 0.687, P less than 0.001). These results confirm previous reports of blunted thermogenesis in obese individuals, but provide no evidence of altered resting metabolic rate or postprandial thermogenesis in women with PCO compared with normal women of similar degree of obesity.

The Numerical Simulation of Coupling Behavior of Soil with Chemical Pollutant Effects

Science.gov (United States)

Liu, Z. J.; Li, X. K.; Tang, L. Q.

2010-05-01

The coupling behavior of clay plays a role in the integrity of clay barriers used in landfills. The clay barriers are subjected to mechanical and thermal effects coupled with hydraulic behavior, also, if the leachates become in contact with the clay liner, chemical effects may lead to some drastic changes in the properties of the clay. A numerical method to simulate the coupling behavior of soil with chemical pollutant effects is presented. Within the framework of Gens-Alonso model describing the constitutive behavior of unsaturated clay presented in reference[1], basing on the work of Wu[2] and Hueckel[3], a constitutive model describing the chemo-thermo-hydro-mechanical(CTHM) coupling behavior of clays in contact with a single organic contaminant is presented. The thermical softening and chemical softening is considered in the presented model. The strain arising in the material due to chemical and thermical effects can be decomposed into two parts: elastic expansion and plastic compaction. The chemical effects are described in terms of the mass concentration of the contaminant. The increases in temperature and contaminant concentration cause decreases of the pre-consolidation pressure and the cohesion. The mechanisms are called thermical softening and chemical softening. The presented coupled CTHM constitutive model has been integrated into the coupled thermo-hydro-mechanical mathematical model including contaminant transport in porous media. To solve the equilibrium equations, the grogram of finite element methods is developed with a stagger algorithm. The mechanisms taking place due to the coupling behaviour of the clay with a single contaminant solute are analysed with the presented numerical method.

Annual report SNET 2003; Rapport annuel SNET 2003

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

This annual report of the SNET (National Society of Electricity and thermic) presents the society activities and the financial report for the year 2003. The society position in the market, the environmental policy, the performance, the workers and financial data are detailed. (A.L.B.)

Annual report SNET 2003

International Nuclear Information System (INIS)

2004-01-01

This annual report of the SNET (National Society of Electricity and thermic) presents the society activities and the financial report for the year 2003. The society position in the market, the environmental policy, the performance, the workers and financial data are detailed. (A.L.B.)

Solar energy in Uruguay. Increase the use of solar panels

International Nuclear Information System (INIS)

Matos, V.

2010-01-01

This article is about the future of the solar energy in Uruguay. The main aspects of this kind of energy are solar thermic which is used for cooking food and heating water through solar collectors as well as the photovoltaics which allows the generation of electricity

Processing method for radioactive sludge

International Nuclear Information System (INIS)

Shoji, Yuichi; Kaneko, Masaaki.

1993-01-01

The concentration of radioactive sludges contained in a storage tank is controlled, thereafter, a filter is charged into a processing vessel to continuously conduct dewatering. Then, the radioactive sludges and an oxidizer are mixed by stirring using a stirring impeller and by vibrations using a vibrator. At the same time, thermic rays are irradiated by using infrared ray lamps to heat and decompose them. Since thermic rays reach the center of the radioactive sludges by the infrared ray lamps, ion exchange resins are sufficiently decomposed and carbonized into inorganic material. Then, a filling hardener such as mortar cement having a good flowability is charged to solidify the wastes. With such procedures, radioactive sludges can be stored under a stable condition for a long period of time by decomposing organic materials into inorganic materials and solidifying them. Further, an operator's radiation exposure dose can remarkably be reduced by applying a predetermined and a stabilization treatment in an identical processing vessel. (N.H.)

Prediction and experimental verification of performance of box type solar cooker. Part II: Cooking vessel with depressed lid

International Nuclear Information System (INIS)

Reddy, Avala Raji; Rao, A.V. Narasimha

2008-01-01

Our previous article (Part I) discussed the theoretical and experimental study of the performance boost obtained by a cooking vessel with central cylindrical cavity on lugs when compared to that of a conventional cylindrical vessel on floor/lugs. This article compares the performance of the cooking vessel with depressed lid on lugs with that of the conventional vessel on lugs. A mathematical model is presented to understand the heat flow process to the cooking vessel and, thereby, to the food material. It is found from the experiments that the cooking vessel with depressed lid results in higher temperature of the thermic fluid loaded in the cooking vessel compared to that of the thermic fluid kept in the conventional vessel when both are placed on lugs. Similar results were obtained by modeling the process mathematically. The average improvement of performance of the vessel with depressed lid is found to be 8.4% better than the conventional cylindrical vessel

Beginning Power BI with Excel 2013 self-service business intelligence using Power Pivot, Power View, Power Query, and Power Map

CERN Document Server

Clark, Dan

2014-01-01

Understanding your company's data has never been easier than with Microsoft's new Power BI package for Excel 2013. Consisting of four powerful tools-Power Pivot, Power View, Power Query and Power Maps-Power BI makes self-service business intelligence a reality for a wide range of users, bridging the traditional gap between Excel users, business analysts and IT experts and making it easier for everyone to work together to build the data models that can give you game-changing insights into your business. Beginning Power BI with Excel 2013 guides you step by step through the process of analyzin

Supercritical fluids technology. Pt. 1 General topics

International Nuclear Information System (INIS)

Marongiu, B.; De Giorgi, M. R.; Porcedda, S.; Cadoni, E.

1998-01-01

Supercritical fluids technology is among the emerging 'clean' technologies, that allows the minimization in the use of chemical and thermic treatments and products irradiation, diminishing the quantity of liquid wastes to be treated. In this first article phase equilibria thermodynamics and fluid mechanics of transport phenomena are reviewed [it

Phytoremediation of high phosphorus soil by annual ryegrass and common bermudagrass harvest

Science.gov (United States)

Removal of soil phosphorus (P) in crop harvest is a remediation option for soils high in P. This four-year field-plot study determined P uptake by annual ryegrass (ARG, Lolium multiflorum Lam.) and common bermudagrass (CB, Cynodon dactylon (L.) Pers.) from Ruston soil (fine-loamy, siliceous, thermic...

Wind Power - A Power Source Enabled by Power Electronics

DEFF Research Database (Denmark)

Blaabjerg, Frede; Chen, Zhe

2004-01-01

. The deregulation of energy has lowered the investment in bigger power plants, which means the need for new electrical power sources may be very high in the near future. Two major technologies will play important roles to solve the future problems. One is to change the electrical power production sources from......The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity. The production, distribution and the use of the energy should be as technological efficient as possible and incentives to save energy at the end-user should be set up...... the conventional, fossil (and short term) based energy sources to renewable energy sources. The other is to use high efficient power electronics in power systems, power production and end-user application. This paper discuss the most emerging renewable energy source, wind energy, which by means of power...

Power program and nuclear power

International Nuclear Information System (INIS)

Chernilin, Yu.F.

1990-01-01

Main points of the USSR power program and the role of nuclear power in fuel and power complex of the country are considered. Data on dynamics of economic indices of electric power generation at nuclear power plants during 1980-1988 and forecasts till 2000 are presented. It is shown that real cost of 1 kW/h of electric power is equal to 1.3-1.8 cop., and total reduced cost is equal to 1.8-2.4 cop

Design and full scale test of a sand bed filter

International Nuclear Information System (INIS)

Kaercher, M.

1991-01-01

All French pressurized water reactor plants are equipped with a containment venting system. this system is designed and implemented by Electricite de France with the technical support of safety authorities (Institute of Protection and Nuclear Safety of Atomic Energy Commission). This paper covers the following items: main assumptions, sizing and design requirements; basic design of the filter resulting from PITEAS R and D program carried out between 1983 and 1989 at Cadarache nuclear center; full scale tests performed in 1990 on FUCHIA loop at Cadarache including description of the loop using plasma torches to generate CsOH aerosols in a steam - air flow, and preliminary results concerning thermohydraulic and thermic behavior under residual power simulated filtration efficiency with CsOH aerosols and iodine; complementary design, including hydrogen risk during condensation period, radiological shieldings of the filter, and heat removal after the filter closure; and conclusion on the validation of the filter

Heat and mass transfers in the jets; Transferts de chaleur et de masse dans les jets

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This day on the heat and mass transfers in the jets, was organized by the SFT (French Society of Thermic) to present the state of the art in the domain. Fifteen presentations allowed the participants to discuss about turbulent flows, simulation of fluid flow and jets impacts. (A.L.B.)

Introduction to electrical power and power electronics

CERN Document Server

Patel, Mukund R

2012-01-01

Power Generation, Distribution, and Utilization AC Power Fundamentals Common Aspects of Power Equipments AC Generator AC and DC Motors Transformer Power Cable Power Distribution Fault Current Analysis System ProtectionEconomic Use of PowerElectrochemical BatteryPower Electronics and Motor Drives Power Electronics Devices DC-DC Converters AC-DC-AC Converters Variable-Frequency Drives Quality of Power Power Converter CoolingAppendixIndex

Power theories for improved power quality

CERN Document Server

Pasko, Marian

2012-01-01

Power quality describes a set of parameters of electric power and the load’s ability to function properly under specific conditions. It is estimated that problems relating to power quality costs the European industry hundreds of billions of Euros annually. In contrast, financing for the prevention of these problems amount to fragments of these costs. Power Theories for Improved Power Quality addresses this imbalance by presenting and assessing a range of methods and problems related to improving the quality of electric power supply. Focusing particularly on active compensators and the DSP based control algorithms, Power Theories for Improved Power Quality introduces the fundamental problems of electrical power. This introduction is followed by chapters which discuss: •‘Power theories’ including their historical development and application to practical problems, •operational principles of active compensator’s DSP control based algorithms using examples and results from laboratory research, and •t...

Bibliographic Review about Solar Hydrogen Production Through Thermochemical Cycles; Revision Bibliografica sobre la Produccion de Hidrogeno Solar Mediante Ciclos Termoquimicos

Energy Technology Data Exchange (ETDEWEB)

Fernandez Saavedra, R.

2007-12-28

This report presents a summary of the different thermical processes used to obtain hydrogen through solar energy, paying more attention to the production of hydrogen from water through thermochemical cycles. In this aspect, it is briefly described the most interesting thermochemical cycles, focusing on thermochemical cycles based on oxides. (Author) 25 refs.

Bibliographic Review about Solar Hydrogen Production Through Thermochemical Cycles; Revision Bibliografica sobre la Produccion de Hidrogeno Solar Mediante Ciclos Termoquimicos

Energy Technology Data Exchange (ETDEWEB)

Fernandez Saavedra, R.

2008-08-06

This report presents a summary of the different thermical processes used to obtain hydrogen through solar energy, paying more attention to the production of hydrogen from water through thermochemical cycles. In this aspect, it is briefly y described the most interesting thermochemical cycles, focusing on thermochemical cycles based on oxides. (Author) 25 refs.

Bibliographic Review about Solar Hydrogen Production Through Thermochemical Cycles

International Nuclear Information System (INIS)

Fernandez Saavedra, R.

2007-01-01

This report presents a summary of the different thermical processes used to obtain hydrogen through solar energy, paying more attention to the production of hydrogen from water through thermochemical cycles. In this aspect, it is briefly described the most interesting thermochemical cycles, focusing on thermochemical cycles based on oxides. (Author) 25 refs

Wind power - a power source now enabled by power electronics

DEFF Research Database (Denmark)

Blaabjerg, Frede; Iov, Florin

2007-01-01

energy at the end-user should be set up. Deregulation of energy has lowered the investment in larger power plants, which means the need for new electrical power sources may be increased in the near future. Two major technologies will play important roles to solve the future problems. One is to change......The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity. It is expected that it has to be doubled within 20 years. The production, distribution and use of the energy should be as technological efficient as possible and incentives to save...... the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. Another is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most emerging...

Macroscopical morphology of deterioration of the stone in the cathedral of Guadíx/Spain

Directory of Open Access Journals (Sweden)

Alcalde, M.

1991-12-01

Full Text Available The main factors of deterioration that affect the Cathedral of Guadíx are of a natural origin, basically thermic and hydraulic, due to its great oscillations in temperature in Summer, the frequency of frosts in Winter and the rains. The lithotypes employed are mainly calcarenite of mean porosite and slightly more compact limestones from the quarries in the area, and marbles. The corresponding deterioration mechanisms are those of differential thermic dilatations caused by thermic jumps, especially in the more compact stones, those of increase in volume in capillaries and interstices, especially by freezing, and those of dissolution. The most serious deterioration indicators are fissures and spalling that affect the most carved elements and which have taken the greater part of the most aerated elements such as the pinnacles to a state to ruin.

Los principales factores de alteración que afectan a la catedral de Guadix son de origen natural, fundamentalmente térmico e hidráulico, por sus grandes oscilaciones de temperatura en verano y por la frecuencia de heladas en invierno, y por la lluvias. Los litotipos empleados son principalmente calcarenitas de porosidad media y calizas algo más compactas, procedentes de canteras de la zona, y mármoles. Los mecanismos de alteración correspondientes son los de dilatación térmica diferencial originados por los saltos térmicos, en especial en las piedras más compactas, los de incremento de volumen en capilares e intersticios, sobre todo por heladicidad, y los de disolución. Los indicadores de alteración más graves son las fisuras y fragmentaciones que afectan a los elementos más labrados y que han llevado al estado de ruina a la mayor parte de los elementos más aireados como los pináculos.

Comparison between Different Power Sources for Emergency Power Supply at Nuclear Power Plants

International Nuclear Information System (INIS)

Lenasson, Magnus

2015-01-01

Currently the Swedish nuclear power plants are using diesel generator sets and to some extent gas turbines as their emergency AC power sources and batteries as their emergency DC power sources. In the laws governing Swedish nuclear activity, no specific power sources are prescribed. On the other hand, diversification of safety functions should be considered, as well as simplicity and reliability in the safety systems. So far the choices of emergency power sources have been similar between different power plants, and therefore this project investigated a number of alternative power sources and if they are suitable for use as emergency power on nuclear power plants. The goals of the project were to: - Define the parameters that are essential for rending a power source suitable for use at a nuclear power plant. - Present the characteristics of a number of power sources regarding the defined parameters. - Compile the suitability of the different power sources. - Make implementation suggestions for the less conventional of the investigated power sources. (unconventional in the investigated application) 10 different power sources in total have been investigated and to various degrees deemed suitable Out of the 10 power sources, diesel generators, batteries and to some extent gas turbines are seen as conventional technology at the nuclear power plants. In relation to them the other power sources have been assessed regarding diversification gains, foremost with regards to external events. The power sources with the largest diversification gains are: Internal steam turbine, Hydro power, Thermoelectric generators. The work should first and foremost put focus on the fact that under the right circumstances there are power sources that can complement conventional power sources and yield substantial diversification gains. This paper is a shortened version of the report 'Comparison between different power sources for emergency power supply at nuclear power plants'. The

Study of the Changes in Composition of Ammonium Diuranate with Progress of Precipitation, and Study of the Properties of Ammonium Diuranate and its Subsequent Products Produced from both Uranyl Nitrate and Uranyl Fluoride Solutions

Directory of Open Access Journals (Sweden)

Subhankar Manna

2017-04-01

Full Text Available Uranium metal used for fabrication of fuel for research reactors in India is generally produced by magnesio-thermic reduction of UF4. Performance of magnesio-thermic reaction and recovery and quality of uranium largely depends on properties of UF4. As ammonium diuranate (ADU is first product in powder form in the process flow-sheet, properties of UF4 depend on properties of ADU. ADU is generally produced from uranyl nitrate solution (UNS for natural uranium metal production and from uranyl fluoride solution (UFS for low enriched uranium metal production. In present paper, ADU has been produced via both the routes. Variation of uranium recovery and crystal structure and composition of ADU with progress in precipitation reaction has been studied with special attention on first appearance of the precipitate Further, ADU produced by two routes have been calcined to UO3, then reduced to UO2 and hydroflorinated to UF4. Effect of two different process routes of ADU precipitation on the characteristics of ADU, UO3, UO2 and UF4 were studied here.

Microstructural characterization and finite element modeling of AZ31 magnesium alloys welded joints

Directory of Open Access Journals (Sweden)

José A. Segarra

2018-03-01

Full Text Available In this article, it has been studied how the microstructure of AZ31 magnesium alloy can be affected by the thermic cycles produced by welding processes, trying to modeling by element finite software the thermic cycles in this material. The AZ31 samples tested were welded using Gas Tugsten Arc Welding (GTAW and different filler materials. For this investigation, optic microscopy, scanning electronic microscopy, and finite elements method software has been used. This work indicates in one hand that in this type of alloys the microconstituyentes are Al-Mn o Al-Mn-Mg compounds, the presence of β-phase cannot be found at room temperature in this research at room, on the other hand the obtained simulation models indicate that the recrystallization takes place in the areas which reach maximum temperatures around 550 °C, this value is also the limit of the dissolution area for the Al-Mn o Al-Mn-Mg precipitated particles which are very likely to act as inhibitors of the corrosion in NaCl electrolytes.

The effects of a low-fat, plant-based dietary intervention on body weight, metabolism, and insulin sensitivity.

Science.gov (United States)

Barnard, Neal D; Scialli, Anthony R; Turner-McGrievy, Gabrielle; Lanou, Amy J; Glass, Jolie

2005-09-01

This study investigated the effect of a low-fat, plant-based diet on body weight, metabolism, and insulin sensitivity, while controlling for exercise in free-living individuals. In an outpatient setting, 64 overweight, postmenopausal women were randomly assigned to a low-fat, vegan diet or a control diet based on National Cholesterol Education Program guidelines, without energy intake limits, and were asked to maintain exercise unchanged. Dietary intake, body weight and composition, resting metabolic rate, thermic effect of food, and insulin sensitivity were measured at baseline and 14 weeks. Mean +/- standard deviation intervention-group body weight decreased 5.8 +/- 3.2 kg, compared with 3.8 +/- 2.8 kg in the control group (P = .012). In a regression model of predictors of weight change, including diet group and changes in energy intake, thermic effect of food, resting metabolic rate, and reported energy expenditure, significant effects were found for diet group (P effect of food (P vegan diet was associated with significant weight loss in overweight postmenopausal women, despite the absence of prescribed limits on portion size or energy intake.

Study of the changes in composition of ammonium diuranate with progress of precipitation, and study of the properties of ammonium diuranate and its subsequent products produced from both uranyl nitrate and uranyl fluoride solutions

International Nuclear Information System (INIS)

Manna, Subhankar; Kumar, Raj; Satpati, Santosh K.; Roy, Saswati B.; Joshi, Jyeshtharaj B.

2017-01-01

Uranium metal used for fabrication of fuel for research reactors in India is generally produced by magnesio-thermic reduction of UF 4 . Performance of magnesio-thermic reaction and recovery and quality of uranium largely depends on properties of UF 4 . As ammonium diuranate (ADU) is first product in powder form in the process flow-sheet, properties of UF 4 depend on properties of ADU. ADU is generally produced from uranyl nitrate solution (UNS) for natural uranium metal production and from uranyl fluoride solution (UFS) for low enriched uranium metal production. In present paper, ADU has been produced via both the routes. Variation of uranium recovery and crystal structure and composition of ADU with progress in precipitation reaction has been studied with special attention on first appearance of the precipitate Further, ADU produced by two routes have been calcined to UO 3 , then reduced to UO 2 and hydroflorinated to UF 4 . Effect of two different process routes of ADU precipitation on the characteristics of ADU, UO 3 , UO 2 and UF 4 were studied here

The power of PowerPoint.

Science.gov (United States)

Niamtu , J

2001-08-01

Carousel slide presentations have been used for academic and clinical presentations since the late 1950s. However, advances in computer technology have caused a paradigm shift, and digital presentations are quickly becoming standard for clinical presentations. The advantages of digital presentations include cost savings; portability; easy updating capability; Internet access; multimedia functions, such as animation, pictures, video, and sound; and customization to augment audience interest and attention. Microsoft PowerPoint has emerged as the most popular digital presentation software and is currently used by many practitioners with and without significant computer expertise. The user-friendly platform of PowerPoint enables even the novice presenter to incorporate digital presentations into his or her profession. PowerPoint offers many advanced options that, with a minimal investment of time, can be used to create more interactive and professional presentations for lectures, patient education, and marketing. Examples of advanced PowerPoint applications are presented in a stepwise manner to unveil the full power of PowerPoint. By incorporating these techniques, medical practitioners can easily personalize, customize, and enhance their PowerPoint presentations. Complications, pitfalls, and caveats are discussed to detour and prevent misadventures in digital presentations. Relevant Web sites are listed to further update, customize, and communicate PowerPoint techniques.

Water Power Research | Water Power | NREL

Science.gov (United States)

Water Power Research Water Power Research NREL conducts water power research; develops design tools ; and evaluates, validates, and supports the demonstration of innovative water power technologies. Photo of a buoy designed around the oscillating water column principle wherein the turbine captures the

Power control device of an atomic power plant

International Nuclear Information System (INIS)

Ootsuka, Shiro; Ito, Takero.

1980-01-01

Purpose: To improve the power controllability of an atomic power plant by improving the controllability, response and stability of the recirculation flow rate. Constitution: The power control device comprises a power detector of the reactor, which detects and operates the reactor power from the thermal power, neutron flux or the process quantity controlling the same, and a deviation detector which seeks deviation between the power signal of the power detector and the power set value of the reactor or power station. By use of the power control device constituted in this manner, the core flow rate is regulated by the power signal of the deviation detector thereby to control the power. (Aizawa, K.)

DC power supplies power management and surge protection for power electronic systems

CERN Document Server

Kularatna, Nihal

2011-01-01

Modern electronic systems, particularly portable consumer electronic systems and processor based systems, are power hungry, compact, and feature packed. This book presents the most essential summaries of the theory behind DC-DC converter topologies of both linear and switching types. The text discusses power supply characteristics and design specifications based on new developments in power management techniques and modern semiconductors entering into the portable electronics market. The author also addresses off-the-line power supplies, digital control of power supply, power supply protection

Power generation by nuclear power plants

International Nuclear Information System (INIS)

Bacher, P.

2004-01-01

Nuclear power plays an important role in the world, European (33%) and French (75%) power generation. This article aims at presenting in a synthetic way the main reactor types with their respective advantages with respect to the objectives foreseen (power generation, resources valorization, waste management). It makes a fast review of 50 years of nuclear development, thanks to which the nuclear industry has become one of the safest and less environmentally harmful industry which allows to produce low cost electricity: 1 - simplified description of a nuclear power generation plant: nuclear reactor, heat transfer system, power generation system, interface with the power distribution grid; 2 - first historical developments of nuclear power; 3 - industrial development and experience feedback (1965-1995): water reactors (PWR, BWR, Candu), RBMK, fast neutron reactors, high temperature demonstration reactors, costs of industrial reactors; 4 - service life of nuclear power plants and replacement: technical, regulatory and economical lifetime, problems linked with the replacement; 5 - conclusion. (J.S.)

Wanted: elbow grease

CERN Document Server

Anaïs Schaeffer

2013-01-01

In Divonne-les-Bains, an association founded by former CERN personnel is restoring the oldest hydroelectric plant in France. The adventure started more than ten years ago, and now you’re invited to take part…   View of the benzole-powered thermic engine from 1907. Georges Leskens, a spritely 85-year-old, is president of the Divonnelectro association. Georges, a former electrical engineer at CERN, now has a new goal: to bring the Moulin David hydroelectric plant in Divonne-les-Bains, which he found in a derelict state in 2001, back to life. “When I entered the plant for the first time, I found several remarkable period machines… and the extent of the damage,” recalls Georges. “Among other things, the town used the building for storing salt and grit for the roads... so I don’t need to tell you what state the mechanisms were in!” Aware of the historical value of the site (see box), Georges convinced the D...

Imperfections study of the smoky quartz from Bahia by X-ray diffraction

International Nuclear Information System (INIS)

D'Aguiar Neto, M.M.F.

1974-01-01

X-ray diffraction techniques were used to study the type of point defects in Smoky quartz from Itambe and Vitoria da Conquista in Bahia. The power method, using the Seemann Bohlin camara (back refletion), was utilized in the analysis of the policrystals, while the monocrystals were studied by means of the precession camara. The positions occupied by the defects in the crystal net were calculated. The results show that while the defects of substitutional impurities predominate in the quartz from Itambe, in the quartz from Vitoria da Conquista the substitutional defects exist in comparable proportions that the interstital ones. Isochronous annealing curves, for both type of smoky quartz indicate an increase in the net parameter to temperature values above the annealing temperatures. Was formulated the hypothesis that providing a thermal energy greater than that of annealing is used, new interstitial defects would be created as a result of a thermic diffusion mechanism. (C.D.G.) [pt

Autonomous power networks based power system

International Nuclear Information System (INIS)

Jokic, A.; Van den Bosch, P.P.J.

2006-01-01

This paper presented the concept of autonomous networks to cope with this increased complexity in power systems while enhancing market-based operation. The operation of future power systems will be more challenging and demanding than present systems because of increased uncertainties, less inertia in the system, replacement of centralized coordinating activities by decentralized parties and the reliance on dynamic markets for both power balancing and system reliability. An autonomous network includes the aggregation of networked producers and consumers in a relatively small area with respect to the overall system. The operation of an autonomous network is coordinated and controlled with one central unit acting as an interface between internal producers/consumers and the rest of the power system. In this study, the power balance problem and system reliability through provision of ancillary services was formulated as an optimization problem for the overall autonomous networks based power system. This paper described the simulation of an optimal autonomous network dispatching in day ahead markets, based on predicted spot prices for real power, and two ancillary services. It was concluded that large changes occur in a power systems structure and operation, most of them adding to the uncertainty and complexity of the system. The introduced concept of an autonomous power network-based power system was shown to be a realistic and consistent approach to formulate and operate a market-based dispatch of both power and ancillary services. 9 refs., 4 figs

Les sources du Moyen Atlas et de Rif (Maroc): Faunistique (description de deux espèces nouvelles de Trichoptères), écologie, intérêt biogéographique

NARCIS (Netherlands)

Giudicelli, Jean; Dakki, Mohamed

1984-01-01

Seven springs in the Middle Atlas and five in the Rif have been studied. These show a great diversity of crenal habitats: water temperature ranges from 8.7° to 21°C, and the flow from 1 l/s to 1,800 l/s. Based on hydrologic and thermic characteristics, a spring typology is provided. The invertebrate

Study of diffusion type cold traps in liquid sodium circuit

International Nuclear Information System (INIS)

Araujo, F.G.B. de.

1974-01-01

The purpose of this thesis is to attain conclusions related with the work of the diffusion type cold traps. Primarily a mathematic formulation is established for a purification process, including the determination of the cold trap thermic field. With parameters obtained from the temperature field, purification characteristics were calculated allowing conclusions concerning the system's performance. (author)

An Enhanced Islanding Microgrid Reactive Power, Imbalance Power, and Harmonic Power Sharing Scheme

DEFF Research Database (Denmark)

He, Jinwei; Lin, Yun Wei; Blaabjerg, Frede

2015-01-01

To address inaccurate power sharing problems in autonomous islanding microgrids, an enhanced droop control method through online virtual impedance adjustment is proposed. First, a term associated with DG reactive power, imbalance power, or harmonic power is added to the conventional real power...

Electric power system / emergency power supply

International Nuclear Information System (INIS)

Dorn, P.G.

1980-01-01

One factor of reliability of reactor safety systems is the integrity of the power supply. The purpose of this paper is a review and a discussion of the safety objectives required for the planning, licensing, manufacture and erection of electrical power systems and components. The safety aspects and the technical background of the systems for - the electric auxiliary power supply system and - the emergency power supply system are outlined. These requirements result specially from the safety standards which are the framework for the studies of safety analysis. The overall and specific requirements for the electrical power supply of the safety systems are demonstrated on a 1300 MW standard nuclear power station with a pressurized water reactor. (orig.)

Wind power in modern power systems

DEFF Research Database (Denmark)

Chen, Zhe

2013-01-01

In recent years, wind power is experiencing a rapid growth, and large-scale wind turbines/wind farms have been developed and connected to power systems. However, the traditional power system generation units are centralized located synchronous generators with different characteristics compared...... with wind turbines. This paper presents an overview of the issues about integrating large-scale wind power plants into modern power systems. Firstly, grid codes are introduced. Then, the main technical problems and challenges are presented. Finally, some possible technical solutions are discussed....

Stockholm Power Tech. Power systems

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-11-01

The proceedings from this symposium is presented in six volumes: Invited speakers` sessions; Power systems; Power electronics; High-voltage technology; Electrical machines and drives; and Information and control systems. This report covers the power systems volume. Separate abstracts have been prepared for 141 of the 145 papers in this volume

Stockholm Power Tech. Power systems

International Nuclear Information System (INIS)

1995-01-01

The proceedings from this symposium is presented in six volumes: Invited speakers' sessions; Power systems; Power electronics; High-voltage technology; Electrical machines and drives; and Information and control systems. This report covers the power systems volume. Separate abstracts have been prepared for 141 of the 145 papers in this volume

Thermoelectric power generator for variable thermal power source

Science.gov (United States)

Bell, Lon E; Crane, Douglas Todd

2015-04-14

Traditional power generation systems using thermoelectric power generators are designed to operate most efficiently for a single operating condition. The present invention provides a power generation system in which the characteristics of the thermoelectrics, the flow of the thermal power, and the operational characteristics of the power generator are monitored and controlled such that higher operation efficiencies and/or higher output powers can be maintained with variably thermal power input. Such a system is particularly beneficial in variable thermal power source systems, such as recovering power from the waste heat generated in the exhaust of combustion engines.

Emergency power systems at nuclear power plants

International Nuclear Information System (INIS)

1982-01-01

This Guide applies to nuclear power plants for which the total power supply comprises normal power supply (which is electric) and emergency power supply (which may be electric or a combination of electric and non-electric). In its present form the Guide provides general guidance for all types of emergency power systems (EPS) - electric and non-electric, and specific guidance (see Appendix A) on the design principles and the features of the emergency electric power system (EEPS). Future editions will include a second appendix giving specific guidance on non-electric power systems. Section 3 of this Safety Guide covers information on considerations that should be taken into account relative to the electric grid, the transmission lines, the on-site electrical supply system, and other alternative power sources, in order to provide high overall reliability of the power supply to the EPS. Since the nuclear power plant operator does not usually control off-site facilities, the discussion of methods of improving off-site reliability does not include requirements for facilities not under the operator's control. Sections 4 to 11 of this Guide provide information, recommendations and requirements that would apply to any emergency power system, be it electric or non-electric

Power Burst Facility: power oscillation problem

International Nuclear Information System (INIS)

Lussie, W.G.; Wadkins, R.P.; Wells, R.A.

1975-01-01

In late 1973 PBF achieved a power level of 15 MW. During this period of operation fluctuations in reactor power were observed. Many possible causes of these fluctuations were considered and a number of nuclear and non-nuclear tests were conducted. Initial instrumentation installed in the core showed coolant outlet temperature variations of 10 0 F for several fuel cannisters and approximately 10 percent power variations at 15 MW. Power spectral density analysis showed a predominant frequency of 0.05 to 0.06 HZ. The testing program to determine the cause of the power oscillations is described

PowerFactory applications for power system analysis

CERN Document Server

Gonzalez-Longatt, Francisco

2014-01-01

This book presents a comprehensive set of guidelines and applications of DIgSILENT PowerFactory, an advanced power system simulation software package, for different types of power systems studies. Written by specialists in the field, it combines expertise and years of experience in the use of DIgSILENT PowerFactory with a deep understanding of power systems analysis. These complementary approaches therefore provide a fresh perspective on how to model, simulate and analyse power systems. It presents methodological approaches for modelling of system components, including both classical and non-

Cost of nuclear power generation judged by power rate

International Nuclear Information System (INIS)

Hirai, Takaharu

1981-01-01

According to estimation guidance, power rates in general are the proper cost plus the specific compensation and adjustment addition. However, the current system of power rates is of power-source development promotion type involving its tax. The structure of power rate determination must be restudied now especially in connection of nuclear power generation. The cost of nuclear power generation as viewed from power rate is discussed as follows: the fear of military application of power plants, rising plant construction costs, the loophole in fuel cost calculation, unreasonable unit power cost, depreciation and repair cost, business compensation, undue business compensation in nuclear power, the costs of nuclear waste management, doubt concerning nuclear power cost, personnel, pumping-up and power transmission costs in nuclear power, energy balance analysis, nuclear power viewed in entropy, the suppression of power consumption. (J.P.N.)

An accurate autonomous islanding microgrid reactive power, imbalance power and harmonic power sharing scheme

DEFF Research Database (Denmark)

He, Jinwei; Li, Yun Wei; Blaabjerg, Frede

2013-01-01

To address inaccurate power sharing problems in autonomous islanding microgrids, an enhanced droop control method through adaptive virtual impedance adjustment is proposed. First, a term associated with DG reactive power, imbalance power or harmonic power is added to the conventional real power...

Smart Power Supply for Battery-Powered Systems

Science.gov (United States)

Krasowski, Michael J.; Greer, Lawrence; Prokop, Norman F.; Flatico, Joseph M.

2010-01-01

A power supply for battery-powered systems has been designed with an embedded controller that is capable of monitoring and maintaining batteries, charging hardware, while maintaining output power. The power supply is primarily designed for rovers and other remote science and engineering vehicles, but it can be used in any battery alone, or battery and charging source applications. The supply can function autonomously, or can be connected to a host processor through a serial communications link. It can be programmed a priori or on the fly to return current and voltage readings to a host. It has two output power busses: a constant 24-V direct current nominal bus, and a programmable bus for output from approximately 24 up to approximately 50 V. The programmable bus voltage level, and its output power limit, can be changed on the fly as well. The power supply also offers options to reduce the programmable bus to 24 V when the set power limit is reached, limiting output power in the case of a system fault detected in the system. The smart power supply is based on an embedded 8051-type single-chip microcontroller. This choice was made in that a credible progression to flight (radiation hard, high reliability) can be assumed as many 8051 processors or gate arrays capable of accepting 8051-type core presently exist and will continue to do so for some time. To solve the problem of centralized control, this innovation moves an embedded microcontroller to the power supply and assigns it the task of overseeing the operation and charging of the power supply assets. This embedded processor is connected to the application central processor via a serial data link such that the central processor can request updates of various parameters within the supply, such as battery current, bus voltage, remaining power in battery estimations, etc. This supply has a direct connection to the battery bus for common (quiescent) power application. Because components from multiple vendors may have

Compensating active power imbalances in power system with large-scale wind power penetration

DEFF Research Database (Denmark)

Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit

2016-01-01

Large-scale wind power penetration can affectthe supply continuity in the power system. This is a matterof high priority to investigate, as more regulating reservesand specified control strategies for generation control arerequired in the future power system with even more highwind power penetrat...

Military power requirements and backup power considerations

International Nuclear Information System (INIS)

Botts, T.E.

1986-01-01

All US Air Force (USAF) facilities have certain critical power requirements that must be met in order to carry out their mission successfully. Internal USAF studies have shown that the mission can degrade precipitously as the available power decreases below the mission critical level. Now, more than ever before, the military and private industry are finding that certain functions, such as automated data processing and automated process control, respond catastrophically to power reductions. Furthermore, increased reliance on electrical power means, in the case of the Air Force, that critical power requirements are anticipated to increase by half over the next 15 yr. For these reasons and others, the USAF is investigating several means of improving the availability of electric power under adverse conditions above that which can be provided by an off-base supplier. Among the approaches to this problem being pursued at this time are a program to improve all sorts of generator sets on a service-wide basis and the Multimegawatt Terrestrial Power (MTP) Program, which is pursuing the design and testing of a small dedicated nuclear power source to provide critical mission power. The purpose of this paper is to provide some insight into some of the issues associated with USAF power programs

Real-time impact of power balancing on power system operation with large scale integration of wind power

DEFF Research Database (Denmark)

Basit, Abdul; Hansen, Anca Daniela; Sørensen, Poul Ejnar

2017-01-01

Highly wind power integrated power system requires continuous active power regulation to tackle the power imbalances resulting from the wind power forecast errors. The active power balance is maintained in real-time with the automatic generation control and also from the control room, where...... power system model. The power system model takes the hour-ahead regulating power plan from power balancing model and the generation and power exchange capacities for the year 2020 into account. The real-time impact of power balancing in a highly wind power integrated power system is assessed...

Ti-Zr sponge material structure, obtained in the course of magnesium-thermal reduction

Energy Technology Data Exchange (ETDEWEB)

Sandler, R A; Aleksandrovskii, S V; Likhterman, V A; Golubev, A A; Kuz' menko, A S

1975-09-01

The paper describes the structure of Ti-Zr sponge for which a magnesium-thermic reduction has been employed. The influence of zirconium upon the sponge porous structure has been studied. The general trend lies in the sponge porosity increase as the content of zirconium grows. However this role is manifested in smaller or larger degrees depending upon the effect of other factors.

On Ti-Zr sponge material structure, obtained in the course of magnesium-thermal reduction

International Nuclear Information System (INIS)

Sandler, R.A.; Aleksandrovskij, S.V.; Likhterman, V.A.; Golubev, A.A.; Kuz'menko, A.S.

1975-01-01

The paper describes the structure of Ti-Zr sponge for which a magnesium-thermic reduction has been employed. The influence of zirconium upon the sponge porous structure has been studied. The general trend lies in the sponge porosity increase as the content of zirconium grows. However this role is manifested in a smaller or larger degrees depending upon the effect of other factors

Ionization of colliding atoms the hard way and the easy way

International Nuclear Information System (INIS)

Jong, M.A.M. de.

1989-01-01

The photoionization of the He(2 1 , 3 S)/He collision system at thermic collision energy has been studied by measurement of the energy distribution of the photoelectrons and comparison of this with the one from spontaneous ionization, in particular transfer ionization during collisions between He ++ ions and Xenon atoms. (h;w). 119 refs.; 44 figs.; 78 schemes; 1 tab

Monte Carlo simulation of hybrid systems: An example

International Nuclear Information System (INIS)

Bacha, F.; D'Alencon, H.; Grivelet, J.; Jullien, E.; Jejcic, A.; Maillard, J.; Silva, J.; Zukanovich, R.; Vergnes, J.

1997-01-01

Simulation of hybrid systems needs tracking of particles from the GeV (incident proton beam) range down to a fraction of eV (thermic neutrons). We show how a GEANT based Monte-Carlo program can achieve this, with a realistic computer time and accompanying tools. An example of a dedicated original actinide burner is simulated with this chain. 8 refs., 5 figs

Hybrid wind power balance control strategy using thermal power, hydro power and flow batteries

OpenAIRE

Gelažanskas, Linas; Baranauskas, Audrius; Gamage, Kelum A.A.; Ažubalis, Mindaugas

2016-01-01

The increased number of renewable power plants pose threat to power system balance. Their intermittent nature makes it very difficult to predict power output, thus either additional reserve power plants or new storage and control technologies are required. Traditional spinning reserve cannot fully compensate sudden changes in renewable energy power generation. Using new storage technologies such as flow batteries, it is feasible to balance the variations in power and voltage within very short...

Power manager and method for managing power

NARCIS (Netherlands)

Burchard, A.T.; Kersten, G.; Molnos, A.M.; Milutinovic, A.; Goossens, K.G.W.; Steffens, E.F.M.

2009-01-01

A power manager (106) and method for managing the power supplied to an electronic device is provided. Furthermore, a system wherein the power supplied to an electronic device is managed is provided. The power manager (106) is operative to monitor a hardware monitor (104) during a monitoring time

Wireless powering for low-power distributed sensors

Directory of Open Access Journals (Sweden)

Popović Zoya B.

2006-01-01

Full Text Available In this paper, an overview of the field of wireless powering is presented with an emphasis on low-power applications. Several rectenna elements and arrays are discussed in more detail: (1 a 10-GHz array for powering sensors in aircraft wings; (2 a single antenna in the 2.4-GHz ISM band for low-power assisted-living sensors; and (3 a broadband array for power harvesting in the 2-18GHz frequency range.

Impacts of Wind Power on Power System Stability

NARCIS (Netherlands)

Vittal, E.; Keane, A.; Slootweg, J.G.; Kling, W.L.; Ackermann, T.

2012-01-01

This chapter examines how wind power will impact the stability of power systems. It focuses on the three aspects of power system stability: voltage stability, rotor angle stability and frequency stability. It completes a detailed analysis as to how wind power in power systems will impact the

Nuclear power/water pumping-up composite power plant

International Nuclear Information System (INIS)

Okamura, Kiyoshi.

1995-01-01

In a nuclear power/water pumping-up composite power plant, a reversible pump for pumping-up power generation connected to a steam turbine is connected to an upper water reservoir and a lower water reservoir. A pumping-up steam turbine for driving the turbine power generator, a hydraulic pump for driving water power generator by water flowing from the upper water reservoir and a steam turbine for driving the pumping-up pump by steams from a nuclear reactor are disposed. When power demand is small during night, the steam turbine is rotated by steams of the reactor, to pump up the water in the lower water reservoir to the upper water reservoir by the reversible pump. Upon peak of power demand during day time, power is generated by the steams of the reactor, as well as the reversible pump is rotated by the flowing water from the upper water reservoir to conduct hydraulic power generation. Alternatively, hydraulic power generation is conducted by flowing water from the upper reservoir. Since the number of energy conversion steps in the combination of nuclear power generation and pumping-up power generation is reduced, energy loss is reduced and utilization efficiency can be improved. (N.H.)

Comprehensive Power Losses Model for Electronic Power Transformer

DEFF Research Database (Denmark)

Yue, Quanyou; Li, Canbing; Cao, Yijia

2018-01-01

and considering the impact of the non-unity power factor and the three-phase unbalanced current, the overall power losses in the distribution network when using the EPT to replace the conventional transformer is analyzed, and the conditions in which the application of the EPT can cause less power losses...... reduced power losses in the distribution network require a comprehensive consideration when comparing the power losses of theEPT and conventional transformer. In this paper, a comprehensive power losses analysis model for the EPT in distribution networks is proposed. By analyzing the EPT self-losses......The electronic power transformer (EPT) has highe rpower losses than the conventional transformer. However, the EPT can correct the power factor, compensate the unbalanced current and reduce the line power losses in the distribution network.Therefore, the higher losses of the EPT and the consequent...

Comprehensive Power Losses Model for Electronic Power Transformer

DEFF Research Database (Denmark)

Yue, Quanyou; Li, Canbing; Cao, Yijia

2018-01-01

The electronic power transformer (EPT) has highe rpower losses than the conventional transformer. However, the EPT can correct the power factor, compensate the unbalanced current and reduce the line power losses in the distribution network.Therefore, the higher losses of the EPT and the consequent...... reduced power losses in the distribution network require a comprehensive consideration when comparing the power losses of theEPT and conventional transformer. In this paper, a comprehensive power losses analysis model for the EPT in distribution networks is proposed. By analyzing the EPT self......-losses and considering the impact of the non-unity power factor and the three-phase unbalanced current, the overall power losses in the distribution network when using the EPT to replace the conventional transformer is analyzed, and the conditions in which the application of the EPT can cause less power losses...

Selectivity of power system protections at power swings in power system

Directory of Open Access Journals (Sweden)

Jan Machowski

2012-12-01

Full Text Available The paper discusses out-of-step protection systems such as: generator pole slip protections, out of step tripping protections, distance protections of step-up transformer, distance protections of transmission lines and transformers, power swing blocking, and special out-of-step protection. It is shown that all these protections make up a protection system, to which a setting concept uniform for the entire power system has to be applied. If a power system is inappropriately equipped with these protections, or their settings are inappropriate, they may operate unselectively, thus contributing to the development of power system blackouts. In the paper the concepts for a real power system are given for the two stages: target stage fully compliant with selectivity criteria, and transitional stage between the current and target stages.

Power Ramp Limitation capabilities of Large PV Power Plants with Active Power Reserves

DEFF Research Database (Denmark)

Bogdan, Craciun; Kerekes, Tamas; Sera, Dezso

2017-01-01

Power Ramp Limitation (PRL) is likely to become a requirement for large scale photovoltaic power plants (LPVPPs) in order to allow the increase of PV penetration levels. Especially in islands with reduced inertia capability, this problem is more stringent: high power ramp can be caused by either...... fast irradiance changes or other participant generators for example wind power, or loads. In order to compensate for the power mismatch, LPVPPs must use Active Power Reserve (APR), by either curtailment or auxiliary storage. The paper proposes a PRL control structure for dynamic APR sizing...... and deployment. The selected test case is the power system of Puerto Rico (PREPA), modeled using the modified IEEE 12 bus benchmark system, with different levels of PV penetration. It is shown that LPVPP with PRL can effectively reduce the ramping rate of the participating generators. Considering that the large...

Wind power integration into the automatic generation control of power systems with large-scale wind power

Directory of Open Access Journals (Sweden)

Abdul Basit

2014-10-01

Full Text Available Transmission system operators have an increased interest in the active participation of wind power plants (WPP in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different possible future scenarios, when wind power production in the power system is high and conventional production from CHPs is at a minimum level. The investigation results of the proposed control strategy have shown that the WPPs can actively help the AGC, and reduce the real-time power imbalance in the power system, by down regulating their production when CHPs are unable to provide the required response.

Wind power integration into the automatic generation control of power systems with large-scale wind power

DEFF Research Database (Denmark)

Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit

2014-01-01

Transmission system operators have an increased interest in the active participation of wind power plants (WPP) in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC......) of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs) and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described...... and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different...

A Review of Power Electronics for Wind Power

Institute of Scientific and Technical Information of China (English)

Zhe CHEN

2011-01-01

The paper reviews the power electronic applications for wind energy systems.Main wind turbine systems with different generators and power electronic converters are described.The electrical topologies of wind farms with power electronic conversion are discussed.Power electronic applications for improving the performance of wind turbines and wind farms in power systems have been illustrated.

Power

DEFF Research Database (Denmark)

Elmholdt, Claus Westergård; Fogsgaard, Morten

2016-01-01

and creativity suggests that when managers give people the opportunity to gain power and explicate that there is reason to be more creative, people will show a boost in creative behaviour. Moreover, this process works best in unstable power hierarchies, which implies that power is treated as a negotiable....... It is thus a central point that power is not necessarily something that breaks down and represses. On the contrary, an explicit focus on the dynamics of power in relation to creativity can be productive for the organisation. Our main focus is to elaborate the implications of this for practice and theory...

Dynamic influences of wind power on the power system

Energy Technology Data Exchange (ETDEWEB)

Rosas, Pedro

2003-03-01

The thesis first presents the basics influences of wind power on the power system stability and quality by pointing out the main power quality issues of wind power in a small-scale case and following, the expected large-scale problems are introduced. Secondly, a dynamic wind turbine model that supports power quality assessment of wind turbines is presented. Thirdly, an aggregate wind farm model that support power quality and stability analysis from large wind farms is presented. The aggregate wind farm model includes the smoothing of the relative power fluctuation from a wind farm compared to a single wind turbine. Finally, applications of the aggregate wind farm model to the power systems are presented. The power quality and stability characteristics influenced by large-scale wind power are illustrated with three cases. In this thesis, special emphasis has been given to appropriate models to represent the wind acting on wind farms. The wind speed model to a single wind turbine includes turbulence and tower shadow effects from the wind and the rotational sampling turbulence due to the rotation of the blades. In a park scale, the wind speed model to the wind farm includes the spatial coherence between different wind turbines. Here the wind speed model is applied to a constant rotational speed wind turbine/farm, but the model is suitable to variable speed wind turbine/farm as well. The cases presented here illustrate the influences of the wind power on the power system quality and stability. The flicker and frequency deviations are the main power quality parameters presented. The power system stability concentrates on the voltage stability and on the power system oscillations. From the cases studied, voltage and the frequency variations were smaller than expected from the large-scale wind power integration due to the low spatial correlation of the wind speed. The voltage quality analysed in a Brazilian power system and in the Nordel power system from connecting large

AC Power Local Network with Multiple Power Routers

Directory of Open Access Journals (Sweden)

Ryo Takahashi

2013-12-01

Full Text Available Controlling power flow and achieving appropriate matching between power sources and loads according to the quality of energy is expected to be one of the approaches to reduce wasted energy consumption. A power router, proposed recently, has the capability of realizing circuit switching in a power distribution network. This study focuses on the feasibility of an AC power routing network system composed of multiple power routers. To evaluate the feasibility, we experimentally confirm the circuit switching operation of the parallel and series configurations of the power routers, so that the network system can be designed by the combination of parallel and series configurations.

Similarities and differences between conventional power and nuclear power

International Nuclear Information System (INIS)

Wang Yingrong

2011-01-01

As the implementation of the national guideline of 'proactively promoting nuclear power development', especially after China decided in 2006 to introduce Westinghouse's AP1000 technology, some of the power groups specialized in conventional power generation, have been participating in the preliminary work and construction of nuclear power projects in certain degrees. Meanwhile, such traditional nuclear power corporations as China National Nuclear Corporation (CNNC) and China Guangdong Nuclear Power Corporation (CGNPC) have also employed some employees with conventional power generation experience. How can these employees who have long been engaged in conventional power generation successfully adapt to the new work pattern, ideology, knowledge, thinking mode and proficiency of nuclear power, so that they can fit in with the work requirements of nuclear power and become qualified as soon as possible? By analyzing the technological, managerial and cultural features of nuclear power, as well as some issues to be kept in mind when engaged in nuclear power, this paper intends to make some contribution to the nuclear power development in the specific period. (author)

Balancing modern Power System with large scale of wind power

DEFF Research Database (Denmark)

Basit, Abdul; Altin, Müfit; Hansen, Anca Daniela

2014-01-01

Power system operators must ensure robust, secure and reliable power system operation even with a large scale integration of wind power. Electricity generated from the intermittent wind in large propor-tion may impact on the control of power system balance and thus deviations in the power system...... frequency in small or islanded power systems or tie line power flows in interconnected power systems. Therefore, the large scale integration of wind power into the power system strongly concerns the secure and stable grid operation. To ensure the stable power system operation, the evolving power system has...... to be analysed with improved analytical tools and techniques. This paper proposes techniques for the active power balance control in future power systems with the large scale wind power integration, where power balancing model provides the hour-ahead dispatch plan with reduced planning horizon and the real time...

Pragmatic power

CERN Document Server

Eccles, William

2008-01-01

Pragmatic Power is focused on just three aspects of the AC electrical power system that supplies and moves the vast majority of electrical energy nearly everywhere in the world: three-phase power systems, transformers, and induction motors. The reader needs to have had an introduction to electrical circuits and AC power, although the text begins with a review of the basics of AC power. Balanced three-phase systems are studied by developing their single-phase equivalents. The study includes a look at how the cost of ""power"" is affected by reactive power and power factor. Transformers are cons

Power System Operation with Large Scale Wind Power Integration

DEFF Research Database (Denmark)

Suwannarat, A.; Bak-Jensen, B.; Chen, Z.

2007-01-01

to the uncertain nature of wind power. In this paper, proposed models of generations and control system are presented which analyze the deviation of power exchange at the western Danish-German border, taking into account the fluctuating nature of wind power. The performance of the secondary control of the thermal......The Danish power system starts to face problems of integrating thousands megawatts of wind power, which produce in a stochastic behavior due to natural wind fluctuations. With wind power capacities increasing, the Danish Transmission System Operator (TSO) is faced with new challenges related...... power plants and the spinning reserves control from the Combined Heat and Power (CHP) units to achieve active power balance with the increased wind power penetration is presented....

Reaction of some macrolide antibiotics with the ribosome. Labeling of the binding site components

International Nuclear Information System (INIS)

Tejedor, F.; Ballesta, J.P.

1986-01-01

Radioactive carbomycin A, niddamycin, tylosin, and spiramycin, but not erythromycin, can be covalently bound to Escherichia coli ribosomes by incubation at 37 degrees C. The incorporation of radioactivity into the particles is inhibited by SH- and activated double bond containing compounds but not by amino groups, suggesting that the reactions may take place by addition to the double bond present in the reactive antibiotics. This thermic reaction must be different from the photoreaction described for some of these macrolides [Tejedor, F., and Ballesta, J. P. G. (1985) Biochemistry 24, 467-472] since tylosin, which is not photoincorporated, is thermically bound to ribosomes. Most of the radioactivity is incorporated into the ribosomal proteins. Two-dimensional gel electrophoresis of proteins labeled by carbomycin A, niddamycin, and tylosin indicates that about 40% of the radioactivity is bound to protein L27; the rest is distributed among several other proteins such as L8, L2, and S12, to differing extents depending on the drug used. These results indicate, in accordance with previous data, that protein L27 plays an important role in the macrolide binding site, confirming that these drugs bind near the peptidyl transferase center of the ribosome

Study of the changes in composition of ammonium diuranate with progress of precipitation, and study of the properties of ammonium diuranate and its subsequent products produced from both uranyl nitrate and uranyl fluoride solutions

Energy Technology Data Exchange (ETDEWEB)

Manna, Subhankar; Kumar, Raj; Satpati, Santosh K.; Roy, Saswati B. [Bhabha Atomic Research Centre, Trombay, Mumbai (India); Joshi, Jyeshtharaj B. [Dept. of Chemical Engineering, Institute of Chemical Technology, Mumbai (India)

2017-04-15

Uranium metal used for fabrication of fuel for research reactors in India is generally produced by magnesio-thermic reduction of UF{sub 4}. Performance of magnesio-thermic reaction and recovery and quality of uranium largely depends on properties of UF{sub 4}. As ammonium diuranate (ADU) is first product in powder form in the process flow-sheet, properties of UF{sub 4} depend on properties of ADU. ADU is generally produced from uranyl nitrate solution (UNS) for natural uranium metal production and from uranyl fluoride solution (UFS) for low enriched uranium metal production. In present paper, ADU has been produced via both the routes. Variation of uranium recovery and crystal structure and composition of ADU with progress in precipitation reaction has been studied with special attention on first appearance of the precipitate Further, ADU produced by two routes have been calcined to UO{sub 3}, then reduced to UO{sub 2} and hydroflorinated to UF{sub 4}. Effect of two different process routes of ADU precipitation on the characteristics of ADU, UO{sub 3}, UO{sub 2} and UF{sub 4} were studied here.

On the nature of the afferent fibers of oculomotor nerve.

Science.gov (United States)

Manni, E; Draicchio, F; Pettorossi, V E; Carobi, C; Grassi, S; Bortolami, R; Lucchi, M L

1989-03-01

The oculogyric nerves contain afferent fibers originating from the ophthalmic territory, the somata of which are located in the ipsilateral semilunar ganglion. These primary sensory neurons project to the Subnucleus Gelatinosus of the Nucleus Caudalis Trigemini, where they make presynaptic contact with the central endings of the primary trigeminal afferents running in the fifth cranial nerve. After complete section of the trigeminal root, the antidromic volleys elicited in the trunk of the third cranial nerve by stimulating SG of NCT consisted of two waves belonging to the A delta and C groups. The area of both components of the antidromic volleys decreased both after bradykinin and hystamine injection into the corresponding cutaneous region and after thermic stimulation of the ipsilateral trigeminal ophthalmic territory. The reduction of such potentials can be explained in terms of collision between the antidromic volleys and those elicited orthodromically by chemical and thermic stimulation. Also, capsaicin applied on the nerve induced an immediate increase, followed by a long lasting decrease, of orthodromic evoked response area. These findings bring further support to the nociceptive nature of the afferent fibers running into the oculomotor nerve.

Grimsel Test Site: heat test, final report

International Nuclear Information System (INIS)

Schneefuss, J.; Glaess, F.; Gommlich, G.; Schmidt, M.

1989-05-01

The Swiss concept for the storage of radioactive waste consists in placing it in compact, dense rock formations. An experiment 'Heat Test' carried out by the 'Gesellschaft fuer Strahlen- und Umweltforschung' in Nagra's Grimsel rock laboratory simulated the heat production of stored radioactive waste. The aim was to evaluate processes for the demonstration of the suitability of a final repository for heat-producing radioactive waste in cristalline rock, to investigate the thermic, mechanic and hydraulic reactions to an artificial heat source, and to develop corresponding calculating models. The duration of the tests was about 3 years. In this report the measured thermic, mechanic and hydraulic reactions are documented and discussed in detail. A simple, rotation symmetrical FEM-model was used for the preparatory and experiment-accompanying modelling of the thermomechanical conditions in the heat test. The test showed that suitable measuring methods for the surveillance of the geomechanics of a final repository are available and that the reactions of the crystalline host rock to the heat source remain locally limited and can be modelled with relatively small effort. 29 refs., 33 figs., 10 tabs

Investigating power control in autonomous power systems with increasing wind power penetration

Energy Technology Data Exchange (ETDEWEB)

Margaris, Ioannis D. [National Technical Univ. of Athens (Greece). Electric Energy Systems Lab.; Hansen, Anca D.; Sorensen, Poul [Risoe National Laboratory, Roskilde (Denmark). Wind Energy Dept.; Hatziargyriou, Nikos D. [National Technical Univ. of Athens (Greece). Electric Energy Systems Lab.; Public Power Corporation S.A., Athens (Greece)

2009-07-01

Increasing levels of wind penetration in autonomous power systems has set intensively high standards with respect to wind turbine technology during the last years. Special features of non-interconnected power systems make security issues rather critical, as the operation of large wind farms like conventional power plants is becoming a necessity. This paper includes the study case of Rhodos island, in Greece, where rapidly increasing wind penetration has started to impose serious security issues for the immediate future. The scenarios studied here correspond to reference year of study 2012 and include wind farms with three different wind turbine technologies - namely Doubly Fed Induction Generator (DFIG), Permanent Magnet Synchronous Generator (PMSG) and Active Stall Induction Generator (ASIG) based wind turbines. Aggregated models of the wind farms are being used and results for different load cases are being analyzed and discussed. The ability of wind farms to assist in some of the power system control services traditionally carried out by conventional synchronous generation is being investigated and discussed. The power grid of the island, including speed governors and automatic voltage regulators, is simulated in the dedicated power system simulation program Power Factory from DIgSILENT. (orig.)

Sexual aggression when power is new: Effects of acute high power on chronically low-power individuals.

Science.gov (United States)

Williams, Melissa J; Gruenfeld, Deborah H; Guillory, Lucia E

2017-02-01

Previous theorists have characterized sexually aggressive behavior as an expression of power, yet evidence that power causes sexual aggression is mixed. We hypothesize that power can indeed create opportunities for sexual aggression-but that it is those who chronically experience low power who will choose to exploit such opportunities. Here, low-power men placed in a high-power role showed the most hostility in response to a denied opportunity with an attractive woman (Studies 1 and 2). Chronically low-power men and women given acute power were the most likely to say they would inappropriately pursue an unrequited workplace attraction (Studies 3 and 4). Finally, having power over an attractive woman increased harassment behavior among men with chronic low, but not high, power (Study 5). People who see themselves as chronically denied power appear to have a stronger desire to feel powerful and are more likely to use sexual aggression toward that end. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Power system stabilizer control for wind power to enhance power system stability

OpenAIRE

Domínguez García, José Luís; Gomis Bellmunt, Oriol; Bianchi, Fernando Daniel; Sumper, Andreas

2011-01-01

The paper presents a small signal stability analysis for power systems with wind farm interaction. Power systems have damping oscillation modes that can be excited by disturbance or fault in the grid. The power converters of the wind farms can be used to reduce these oscillations and make the system more stable. These ideas are explored to design a power system stabilized (PSS) for a network with conventional generators and a wind farm in order to increase the damping of the oscillation...

Wind farm - A power source in future power systems

DEFF Research Database (Denmark)

Chen, Zhe; Blaabjerg, Frede

2009-01-01

wind turbines and wind farms, and then introduces the wind power development and wind farms. An optimization platform for designing electrical systems of offshore wind farms is briefed. The major issues related to the grid connection requirements and the operation of wind turbines/farms in power......The paper describes modern wind power systems, introduces the issues of large penetration of wind power into power systems, and discusses the possible methods of making wind turbines/farms act as a power source, like conventional power plants in power systems. Firstly, the paper describes modern...... systems are illustrated....

Low Power Design with High-Level Power Estimation and Power-Aware Synthesis

CERN Document Server

Ahuja, Sumit; Shukla, Sandeep Kumar

2012-01-01

Low-power ASIC/FPGA based designs are important due to the need for extended battery life, reduced form factor, and lower packaging and cooling costs for electronic devices. These products require fast turnaround time because of the increasing demand for handheld electronic devices such as cell-phones, PDAs and high performance machines for data centers. To achieve short time to market, design flows must facilitate a much shortened time-to-product requirement. High-level modeling, architectural exploration and direct synthesis of design from high level description enable this design process. This book presents novel research techniques, algorithms,methodologies and experimental results for high level power estimation and power aware high-level synthesis. Readers will learn to apply such techniques to enable design flows resulting in shorter time to market and successful low power ASIC/FPGA design. Integrates power estimation and reduction for high level synthesis, with low-power, high-level design; Shows spec...

A Review of Power Electronics for Wind Power

DEFF Research Database (Denmark)

Chen, Zhe

2011-01-01

The paper reviews the power electronic applications for wind energy systems. Main wind turbine systems with different generators and power electronic converters are described. The electrical topologies of wind farms with power electronic conversion are discussed. Power electronic applications...

Power generation costs. Coal - nuclear power

International Nuclear Information System (INIS)

1979-01-01

This supplement volume contains 17 separate chapters investigating the parameters which determine power generation costs on the basis of coal and nuclear power and a comparison of these. A detailed calculation model is given. The complex nature of this type of cost comparison is shown by a review of selected parameter constellation for coal-fired and nuclear power plants. The most favourable method of power generation can only be determined if all parameters are viewed together. One quite important parameter is the load factor, or rather the hours of operation. (UA) 891 UA/UA 892 AMO [de

Power Electronics

DEFF Research Database (Denmark)

Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

2008-01-01

is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

Nuclear and thermal power plant power ramping capability

International Nuclear Information System (INIS)

Golovach, E.A.

1983-01-01

The possibilities of step power increase by NPP and TPP units under emergency conditions of power grids operation are considered. The data analysis has shown that power units ramping capability with WWER-440, WWER-1000 and RBMK-1000 reactors is higher than that of 300 MW power units on fossil fuel, at the initial time interval (0-30 s). These NPP power units satisfy as to ramping capability the energy system requirements. Higher NPP power units ramping capability is explained by the fact that relative pressure before turbine valves is decreased less than in straight-through boilers while the steam volumes time constant of steam separator-superheaters is less than that of intermediate superheatings. Higher power unit ramping capability with WWER-440 and RBMK-1000 reactors as compared with the WWER-1000 reactor is pointed out as well as the increase of WWER-1000 power unit capability using high-speed turbines

Some power uprate issues in nuclear power plants

International Nuclear Information System (INIS)

Tipping, Philip

2008-01-01

Issues and themes concerned with nuclear power plant uprating are examined. Attention is brought to the fact that many candidate nuclear power plants for uprating have anyway been operated below their rated power for a significant part of their operating life. The key issues remain safety and reliability in operation at all times, irrespective of the nuclear power plant's chronological or design age or power rating. The effects of power uprates are discussed in terms of material aspects and expected demands on the systems, structures and components. The impact on operation and maintenance methods is indicated in terms of changes to the ageing surveillance programmes. Attention is brought to the necessity checking or revising operator actions after power up-rating has been implemented

Power market model with energy- and power dimension

International Nuclear Information System (INIS)

Johnsen, T.A.; Larsen, B.M.

1995-01-01

This report discusses a mathematical model of the Norwegian power market. The year is divided into three seasons. Each season is subdivided into a high-load period and a low-load period according to the demand. High-load occurs in daytime on workdays while low-load occurs at night and on holidays. The model is intended to be a tool for studying variations in prices, production, demand and trade throughout the year in a market of free competition. The model establishes equilibrium prices of electricity in Norway in high-load and low-load periods. Equilibrium prices with added transport tariffs and charges give customer an indication of the cost of using electricity. And the equilibrium prices indicate to the power producers the value of further energy or power capacity. Examples of calculations using the model show that extended export and import between Norway and other countries affect power prices and production in Norway. In the examples, power intensive industry and wood processing are subjected to market prices on energy. World market prices which give unilateral power export in the high-load periods cause the Norwegian power prices to rise strongly. If to the export from Norway in periods of high-load there corresponds import in periods of low-load, then the pressure on the prices in the power market is significantly reduced. A more extensive power exchange implies that foreign power producers may use the Norwegian power system to avoid large variations in their thermal power production. 23 refs., 21 figs., 1 tab

Fuel-cell based power generating system having power conditioning apparatus

Science.gov (United States)

Mazumder, Sudip K.; Pradhan, Sanjaya K.

2010-10-05

A power conditioner includes power converters for supplying power to a load, a set of selection switches corresponding to the power converters for selectively connecting the fuel-cell stack to the power converters, and another set of selection switches corresponding to the power converters for selectively connecting the battery to the power converters. The power conveners output combined power that substantially optimally meets a present demand of the load.

High impact data visualization with Power View, Power Map, and Power BI

CERN Document Server

Aspin, Adam

2014-01-01

High Impact Data Visualization with Power View, Power Map, and Power BI helps you take business intelligence delivery to a new level that is interactive, engaging, even fun, all while driving commercial success through sound decision-making. Learn to harness the power of Microsoft's flagship, self-service business intelligence suite to deliver compelling and interactive insight with remarkable ease. Learn the essential techniques needed to enhance the look and feel of reports and dashboards so that you can seize your audience's attention and provide them with clear and accurate information. Al

On Nonlinear Inverse Problems of Heat Transfer with Radiation Boundary Conditions: Application to Dehydration of Gypsum Plasterboards Exposed to Fire

OpenAIRE

Belmiloudi, A.; Mahé, F.

2014-01-01

International audience; The paper investigates boundary optimal controls and parameter estimates to the well-posedness nonlinear model of dehydration of thermic problems. We summarize the general formulations for the boundary control for initial-boundary value problem for nonlinear partial differential equations modeling the heat transfer and derive necessary optimality conditions, including the adjoint equation, for the optimal set of parameters minimizing objective functions J. Numerical si...

The tritium labelling of ibuprofen by heterogeneous catalytic exchange

International Nuclear Information System (INIS)

Santamaria, J.; Rebollo, D.V.; Rivera, P.; Estaban, M.

1986-01-01

The tritium labelling of 2-(4-isobutylphenyl) propionic acid (ibuprofen) was performed. The method employed was heterogeneous catalytic exchange between ibuprofen and tritiated water. Prior to labelling, thermic stability of ibuprofen was studied. Purification was accomplished through thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Concentration, purity and specific activity of the labelled compound were determined by ultraviolet, HPLC and liquid scintillation techniques. (author)

Numerical solution of Stefan's problem to heterogeneous materials

International Nuclear Information System (INIS)

Basombrio, F.G.

1996-01-01

We present an extension of the methodology developed by R.H. Nochetto et al. to solve the Stefan problem, to situations for which the physical properties are dependent on the spatial point (thermic non-homogeneous materials). In this report, the theoretical and computational aspects are described. With the purpose of showing the performance of programme FASES2, two illustrative examples are included. (author). 6 refs., 2 figs

amylase from cockroach, Periplaneta americana

African Journals Online (AJOL)

STORAGESEVER

2008-08-04

Aug 4, 2008 ... The enzyme was stable up to 55°C and its pH stability was in range of 5.6 - 6.6. .... acrylamide gel and by gel filtration chromatography. Gel filtration .... Activity at 55 °C. Figure 8. Thermic inactivation at 37°C and 55°C of Periplaneta americana α-amylase. Thermal stability of the enzyme was followed for 1 h.

Nuclear power and other thermal power

International Nuclear Information System (INIS)

Bakke, J.

1978-01-01

Some philosophical aspects of mortality statistics are first briefly mentioued, then the environmental problems of, first, nuclear power plants, then fossil fuelled power plants are summarised. The effects of releases of carbon dioxide, sulphur dioxide and nitrogen oxides are briefly discussed. The possible health effects of radiation from nuclear power plants and those of gaseous and particulate effluents from fossil fuel plants are also discussed. It is pointed out that in choosing between alternative evils the worst course is to make no choice at all, that is, failure to install thermal power plants will lead to isolated domestic burning of fossil fuels which is clearly the worst situation regarding pollution. (JIW)

Bidding Strategy of Virtual Power Plant with Energy Storage Power Station and Photovoltaic and Wind Power

Directory of Open Access Journals (Sweden)

Zhongfu Tan

2018-01-01

Full Text Available For the virtual power plants containing energy storage power stations and photovoltaic and wind power, the output of PV and wind power is uncertain and virtual power plants must consider this uncertainty when they participate in the auction in the electricity market. In this context, this paper studies the bidding strategy of the virtual power plant with photovoltaic and wind power. Assuming that the upper and lower limits of the combined output of photovoltaic and wind power are stochastically variable, the fluctuation range of the day-ahead energy market and capacity price is stochastically variable. If the capacity of the storage station is large enough to stabilize the fluctuation of the output of the wind and photovoltaic power, virtual power plants can participate in the electricity market bidding. This paper constructs a robust optimization model of virtual power plant bidding strategy in the electricity market, which considers the cost of charge and discharge of energy storage power station and transmission congestion. The model proposed in this paper is solved by CPLEX; the example results show that the model is reasonable and the method is valid.

Power Quality in DC Power Distribution Systems and Microgrids

Directory of Open Access Journals (Sweden)

Stephen Whaite

2015-05-01

Full Text Available This review paper discusses power quality considerations for direct current (DC electric power distribution systems, particularly DC microgrids. First, four selected sample DC architectures are discussed to provide motivation for the consideration of power quality in DC systems. Second, a brief overview of power quality challenges in conventional alternating current (AC distribution systems is given to establish the field of power quality. Finally, a survey of literature addressing power quality issues in DC systems is presented, and necessary power quality considerations in DC distribution system design and operation are discussed.

Economic Operation of Power Systems with Significant Wind Power Penetration

DEFF Research Database (Denmark)

Farashbashi-Astaneh, Seyed-Mostafa

This dissertation addresses economic operation of power systems with high penetration of wind power. Several studies are presented to address the economic operation of power systems with high penetration of variable wind power. The main concern in such power systems is high variability...... and unpredictability. Unlike conventional power plants, the output power of a wind farm is not controllable. This brings additional complexity to operation and planning of wind dominant power systems. The key solution in face of wind power uncertainty is to enhance power system flexibility. The enhanced flexibility......, cooperative wind-storage operation is studied. Lithium-Ion battery units are chosen as storage units. A novel formulation is proposed to investigate optimal operation of a storage unit considering power system balancing conditions and wind power imbalances. An optimization framework is presented to increase...

A Cool Urban Island Change 1990 - 2014. Comparative Bioclimatic Analysis in a Desert Climate, the Case of Antofagasta City Square

Science.gov (United States)

Pérez Lancellotti, Gino; Ziede Bize, Marcela

2017-10-01

This article proposes to make a comparative bioclimatic analysis from 1990 to 2014 of the main square of Antofagasta, a coastal desert city in Chile, which was remodelled in 1995, and shows how the redesigning of green areas affects the microclimatic conditions and thermal comfort of the urban space. Ex ante measurements dating 1990 were compared with ex post results from 2014. Data were obtained in both cases in the month of September at different times of a day and in different climate conditions. The variables studied were: land surface temperature, humidity, wind speed, amount of light and square use frequency inside the square and in surrounding streets. The temperatures are not statistically different during the years 1990 and 2014 for the city of Antofagasta. The main layout of the square has not changed, and inside the square it is similar for both periods, but new species were introduced and bigger trees with shadow projection were cut down. The square had a micro-climate role in 2014 as well as in 1990. The highest frequency zone with an important surface lost it is comfort thermic condition with an increase of 1°C. Other smaller zones with less relevance for users gained in cooling with a 0.5°C reduction. The new design has been detrimental to the intensity of its micro climatic regulatory function affecting the thermic comfort of the square’s internal spaces, especially those formerly protected by shadow, which mitigate a high solar radiation. The study results suggest that bio-climatic analysis of public open spaces is a key component for the design of future projects as a heat mitigating tool in the context of climate change. Research question is: How does the redesign of the square impact a cool urban island and the thermic comfort of users? Significant differences between data in situ collected in 1990 and 2014. Thermal comfort was negatively affected by the redesign in the square. The square is still a cool island but with less strength.

Laminated multilayer sheet structure and its utilization

International Nuclear Information System (INIS)

Chiba, K.; Itoh, K.; Mitani, Y.; Sobajima, S.; Yonemura, U.

1980-01-01

A laminated multilayer sheet structure is described comprising (A) an opaque flexible sheet layer, and (B) a flexible layer laminated on the surface of layer (A) and composed of a transparent thermic ray reflecting layer (B 1 ) bonded to a transparent synthetic resin layer (B 2 ), said layer (B 1 ) being a transparent thermic ray reflecting layer composed of (I) a layer of a metal having a thickness of about 50 to about 600 A, said metal being selected from the group consisting of gold, silver, copper, aluminum and a mixture of alloy of at least two of said metals, and (II) a high refractive substance layer having a thickness of about 50 to about 600 A, of an oxide of titanium derived from a layer of an organic titanium compound of the formula Ti 1 O/sub m/R/sub n/, where R is alkyl of 1-20 carbon atoms, l=1-30, m=4+3(1-1), and n=4+2(1-1), and containing the organic residual moiety of the organic titanium compound, the amount of said organic residual moiety being 0.1 to 30% by weight based on the weight of the high refractive substance layer; or said layer (B 1 ) being a transparent semiconductive layer having a thickness of about 500 to about 5,000 a and being composed of a compound selected from the group consisting of indium oxide, tin oxide, cadmium oxide, antimony oxide, copper iodide, and a mixture of at least two of said compounds. A method is described for heat-insulating a room, which comprises applying to the surface of a floor, wall, ceiling or partition in the room a laminated multilayer sheet structure comprising (A) an opaque flexible sheet layer, and (B) a flexible layer laminated on the surface of layer (A) and composed of a transparent thermic ray reflecting layer (B 1 ) bonded to a transparent synthetic resin layer

Análise da contaminação parasitária em compostos orgânicos produzidos com biossólidos de esgoto doméstico e resíduos agropecuários Analysis of parasitological contamination in organic composts with sewage sludge and agricultural residues

Directory of Open Access Journals (Sweden)

Eduardo Robson Duarte

2008-08-01

Full Text Available Este estudo avaliou a contaminação por ovos de helmintos, cistos e oocistos de protozoários em compostos orgânicos utilizando lodo de esgoto doméstico e resíduos agropecuários. Foram realizadas análises parasitológicas em amostras de 25 diferentes compostos orgânicos, antes e após tratamento térmico a 60°C durante 12 horas. Os resultados demonstraram elevada contaminação parasitária em todos os compostos analisados antes do tratamento e a não redução dessa contaminação após o tratamento térmico. A identificação das larvas obtidas em coproculturas antes e após o tratamento térmico dos compostos indicou que os gêneros mais freqüentemente observados foram Cooperia e Trichostrongylus, que são nematóides gastrintestinais de ruminantes. Estes resultados demonstram que ovos de helmintos podem permanecer viáveis mesmo após o processo de compostagem e o tratamento térmico. Os compostos produzidos com lodo de esgoto doméstico e resíduo agropecuários, utilizando esses processos de tratamentos, podem constituir riscos de contaminação para humanos e animais.This research aimed at evaluating the cysts, oocysts and eggs contamination before and after thermal treatment of 60°C for 12 hours, in 25 different organic composts produced with biosolids from domestic waste-water treatment and animal and agricultural residues. The results showed high parasitological contamination for all organic composts before the treatment and these contaminations were not reduced after thermic treatment. The larva identification in coprocultures before and after thermic treatment showed Cooperia spp. and Trichostrongylus spp. were the most prevalent nematodes. These results demonstrated that helmintus’ eggs can remain viable even after the composing and thermic treatment. The obtained composition with sewage sludge and agricultural residues through these treatment processes can establish contamination risks for humans and animals.

Liberation of electric power and nuclear power generation

International Nuclear Information System (INIS)

Yajima, Masayuki

2000-01-01

In Japan, as the Rule on Electric Business was revised after an interval of 35 years in 1995, and a competitive bid on new electric source was adopted after 1996 fiscal year, investigation on further competition introduction to electric power market was begun by establishment of the Basic Group of the Electric Business Council in 1997. By a report proposed on January, 1999 by the Group, the Rule was revised again on March, 1999 to start a partial liberation or retail of the electric power from March, 2000. From a viewpoint of energy security and for solution of global environmental problem in Japan it has been decided to positively promote nuclear power in future. Therefore, it is necessary to investigate how the competition introduction affects to development of nuclear power generation and what is a market liberation model capable of harmonizing with the development on liberation of electric power market. Here was elucidated on effect of the introduction on previous and future nuclear power generation, after introducing new aspects of nuclear power problems and investigating characteristic points and investment risks specific to the nuclear power generation. And, by investigating some possibilities to development of nuclear power generation under liberation models of each market, an implication was shown on how to be future liberation on electric power market in Japan. (G.K.)

Balancing computation and communication power in power constrained clusters

Science.gov (United States)

Piga, Leonardo; Paul, Indrani; Huang, Wei

2018-05-29

Systems, apparatuses, and methods for balancing computation and communication power in power constrained environments. A data processing cluster with a plurality of compute nodes may perform parallel processing of a workload in a power constrained environment. Nodes that finish tasks early may be power-gated based on one or more conditions. In some scenarios, a node may predict a wait duration and go into a reduced power consumption state if the wait duration is predicted to be greater than a threshold. The power saved by power-gating one or more nodes may be reassigned for use by other nodes. A cluster agent may be configured to reassign the unused power to the active nodes to expedite workload processing.

Critical success factors for BOT electric power projects in China: Thermal power versus wind power

Energy Technology Data Exchange (ETDEWEB)

Zhao, Zhen-Yu. [School of Business Administration, North China Electric Power University, Beijing 102206 (China); Zuo, Jian; Zillante, George [School of Natural and Built Environments, University of South Australia, Adelaide 5001 (Australia); Wang, Xin-Wei [Shandong Nuclear Power Equipment Manufacturing Co. Ltd, Haiyang, Shandong 265118 (China)

2010-06-15

Chinese electric power industry has adopted Build-Operate-Transfer (BOT) approach in a number of projects to alleviate the pressure of sole state-owned investment. The Chinese government has taken enormous efforts to create an environment to facilitate the application of BOT approach in electric power projects. Moreover, the growing attention on the sustainability issues puts the traditional major source of electricity - thermal power project under more strict scrutiny. As a result, various renewable energy projects, particularly the wind power projects have involved private sector funds. Both thermal power and wind power projects via BOT approach have met with a varying degree of success. Therefore, it is imperative to understand the factors contributing towards the success of both types of BOT power projects. Using an extensive literature survey, this paper identifies 31 success factors under 5 categories for Chinese BOT electric power projects. This is followed by a questionnaire survey to exam relative significance of these factors. The results reveal the different levels of significance of success factors for BOT thermal power projects versus wind power projects. Finally, survey results were analyzed to explore the underlying construction and distributions among the identified success factors. This study provides a valuable reference for all involved parties that are interested in developing BOT electric power projects in China. (author)

An ecological solution in power development strategy: hydroelectric Power

International Nuclear Information System (INIS)

Ionescu, S.; Teodorescu, D.

1994-01-01

One of the fundamental criteria in establishing the power development strategy is represented by the environmental protection. Besides increasing the power efficiency for users, the hydro power stands for a handy alternative to generate thermal power. Comparatively, if hydro power is properly planed and developed, it could allow conservation of fossil fuel resources (as it makes use of a renewable resources) and avoids air and water pollution and in addition would lead to certain positive effects upon the natural and anthropic environment (flood routing, optimizes the power supply-demand relationship, and so on). By making use of the data available in the international specific literature and the information on the power development strategy in Romania the effects incurred by hydro power are both qualitatively and quantitatively emphasized as compared to alternative power generation by fossil fuel combustion. The proposal is made to adopt certain law regulations as well as a methodology to evaluate the general efficiency of various types of power generating devices suiting the particular conditions of Romania and taking into account the social cost as well as environmental effects. Hence a power development strategy could be undertaking at the national level provided it meets the requirements of both power system and environment protection. (Author)

Alternative off-site power supply improves nuclear power plant safety

International Nuclear Information System (INIS)

Gjorgiev, Blaže; Volkanovski, Andrija; Kančev, Duško; Čepin, Marko

2014-01-01

Highlights: • Additional power supply for mitigation of the station blackout event in NPP is used. • A hydro power plant is considered as an off-site alternative power supply. • An upgrade of the probabilistic safety assessment from its traditional use is made. • The obtained results show improvement of nuclear power plant safety. - Abstract: A reliable power system is important for safe operation of the nuclear power plants. The station blackout event is of great importance for nuclear power plant safety. This event is caused by the loss of all alternating current power supply to the safety and non-safety buses of the nuclear power plant. In this study an independent electrical connection between a pumped-storage hydro power plant and a nuclear power plant is assumed as a standpoint for safety and reliability analysis. The pumped-storage hydro power plant is considered as an alternative power supply. The connection with conventional accumulation type of hydro power plant is analysed in addition. The objective of this paper is to investigate the improvement of nuclear power plant safety resulting from the consideration of the alternative power supplies. The safety of the nuclear power plant is analysed through the core damage frequency, a risk measure assess by the probabilistic safety assessment. The presented method upgrades the probabilistic safety assessment from its common traditional use in sense that it considers non-plant sited systems. The obtained results show significant decrease of the core damage frequency, indicating improvement of nuclear safety if hydro power plant is introduced as an alternative off-site power source

Power Talk

DEFF Research Database (Denmark)

Angjelichinoski, Marko; Stefanovic, Cedomir; Popovski, Petar

2016-01-01

A standard way to realize communication in microgrid control is to use an external communication network, such as modems for wireless or power-line communication, whose implementation may be inefficient in terms of deployment cost, complexity, and system stability. In this chapter we present......, while its reliability and availability draw on the reliability and availability of the microgrid power transmission system....... a communication solution, denoted as power talk, which is solely based on the use of the existing microgrid power equipment (i.e., power electronics and buses). The pivotal idea is to modulate information in the power-related parameters of the microgrid buses by use of the flexibility of power electronic...

Switching power converters medium and high power

CERN Document Server

Neacsu, Dorin O

2013-01-01

An examination of all of the multidisciplinary aspects of medium- and high-power converter systems, including basic power electronics, digital control and hardware, sensors, analog preprocessing of signals, protection devices and fault management, and pulse-width-modulation (PWM) algorithms, Switching Power Converters: Medium and High Power, Second Edition discusses the actual use of industrial technology and its related subassemblies and components, covering facets of implementation otherwise overlooked by theoretical textbooks. The updated Second Edition contains many new figures, as well as

Power in Households: Disentangling Bargaining Power

OpenAIRE

Mabsout, Ramzi; Staveren, Irene

2009-01-01

textabstractIntroduction Within the household bargaining literature, bargaining power is generally understood in terms of economic resources, such as income or assets. Empirical analyses of women’s bargaining power in households in developed and developing countries find that, in general, higher female incomes lead to higher bargaining power, which in turn tends to increase women’s relative wellbeing (Quisumbing, 2003). For assets, the empirical literature comes up with similar results, indic...

Self-Powered Functional Device Using On-Chip Power Generation

KAUST Repository

Hussain, Muhammad Mustafa

2012-01-26

An apparatus, system, and method for a self-powered device using on-chip power generation. In some embodiments, the apparatus includes a substrate, a power generation module on the substrate, and a power storage module on the substrate. The power generation module may include a thermoelectric generator made of bismuth telluride.

Self-Powered Functional Device Using On-Chip Power Generation

KAUST Repository

Hussain, Muhammad Mustafa

2012-01-01

An apparatus, system, and method for a self-powered device using on-chip power generation. In some embodiments, the apparatus includes a substrate, a power generation module on the substrate, and a power storage module on the substrate. The power generation module may include a thermoelectric generator made of bismuth telluride.

Power conditioning unit for photovoltaic power systems

Science.gov (United States)

Beghin, G.; Nguyen Phuoc, V. T.

Operational features and components of a power conditioning unit for interconnecting solar cell module powers with a utility grid are outlined. The two-stage unit first modifies the voltage to desired levels on an internal dc link, then inverts the current in 2 power transformers connected to a vector summation control to neutralize harmonic distortion up to the 11th harmonic. The system operates in parallel with the grid with extra inductors to absorb line-to-line voltage and phase differences, and permits peak power use from the PV array. Reactive power is gained internally, and a power system controller monitors voltages, frequencies, and currents. A booster preregulator adjusts the input voltage from the array to provide voltage regulation for the inverter, and can commutate 450 amps. A total harmonic distortion of less than 5 percent is claimed, with a rating of 5 kVA, 50/60 Hz, 3-phase, and 4-wire.

When Power Shapes Interpersonal Behavior: Low Relationship Power Predicts Men’s Aggressive Responses to Low Situational Power

Science.gov (United States)

Overall, Nickola C.; Hammond, Matthew D.; McNulty, James K.; Finkel, Eli J.

2016-01-01

When does power in intimate relationships shape important interpersonal behaviors, such as psychological aggression? Five studies tested whether possessing low relationship power was associated with aggressive responses, but (1) only within power-relevant relationship interactions when situational power was low, and (2) only by men because masculinity (but not femininity) involves the possession and demonstration of power. In Studies 1 and 2, men lower in relationship power exhibited greater aggressive communication during couples’ observed conflict discussions, but only when they experienced low situational power because they were unable to influence their partner. In Study 3, men lower in relationship power reported greater daily aggressive responses toward their partner, but only on days when they experienced low situational power because they were either (a) unable to influence their partner or (b) dependent on their partner for support. In Study 4, men who possessed lower relationship power exhibited greater aggressive responses during couples’ support-relevant discussions, but only when they had low situational power because they needed high levels of support. Study 5 provided evidence for the theoretical mechanism underlying men’s aggressive responses to low relationship power. Men who possessed lower relationship power felt less manly on days they faced low situational power because their partner was unwilling to change to resolve relationship problems, which in turn predicted greater aggressive responses to their partner. These results demonstrate that fully understanding when and why power is associated with interpersonal behavior requires differentiating between relationship and situational power. PMID:27442766

Power oscillation suppression by robust SMES in power system with large wind power penetration

International Nuclear Information System (INIS)

Ngamroo, Issarachai; Cuk Supriyadi, A.N.; Dechanupaprittha, Sanchai; Mitani, Yasunori

2009-01-01

The large penetration of wind farm into interconnected power systems may cause the severe problem of tie-line power oscillations. To suppress power oscillations, the superconducting magnetic energy storage (SMES) which is able to control active and reactive powers simultaneously, can be applied. On the other hand, several generating and loading conditions, variation of system parameters, etc., cause uncertainties in the system. The SMES controller designed without considering system uncertainties may fail to suppress power oscillations. To enhance the robustness of SMES controller against system uncertainties, this paper proposes a robust control design of SMES by taking system uncertainties into account. The inverse additive perturbation is applied to represent the unstructured system uncertainties and included in power system modeling. The configuration of active and reactive power controllers is the first-order lead-lag compensator with single input feedback. To tune the controller parameters, the optimization problem is formulated based on the enhancement of robust stability margin. The particle swarm optimization is used to solve the problem and achieve the controller parameters. Simulation studies in the six-area interconnected power system with wind farms confirm the robustness of the proposed SMES under various operating conditions

Power oscillation suppression by robust SMES in power system with large wind power penetration

Science.gov (United States)

Ngamroo, Issarachai; Cuk Supriyadi, A. N.; Dechanupaprittha, Sanchai; Mitani, Yasunori

2009-01-01

The large penetration of wind farm into interconnected power systems may cause the severe problem of tie-line power oscillations. To suppress power oscillations, the superconducting magnetic energy storage (SMES) which is able to control active and reactive powers simultaneously, can be applied. On the other hand, several generating and loading conditions, variation of system parameters, etc., cause uncertainties in the system. The SMES controller designed without considering system uncertainties may fail to suppress power oscillations. To enhance the robustness of SMES controller against system uncertainties, this paper proposes a robust control design of SMES by taking system uncertainties into account. The inverse additive perturbation is applied to represent the unstructured system uncertainties and included in power system modeling. The configuration of active and reactive power controllers is the first-order lead-lag compensator with single input feedback. To tune the controller parameters, the optimization problem is formulated based on the enhancement of robust stability margin. The particle swarm optimization is used to solve the problem and achieve the controller parameters. Simulation studies in the six-area interconnected power system with wind farms confirm the robustness of the proposed SMES under various operating conditions.

Is power-space a continuum? Distance effect during power judgments.

Science.gov (United States)

Jiang, Tianjiao; Zhu, Lei

2015-12-01

Despite the increasing evidence suggesting that power processing can activate vertical space schema, it still remains unclear whether this power-space is dichotomic or continuous. Here we tested the nature of the power-space by the distance effect, a continuous property of space cognition. In two experiments, participants were required to judge the power of one single word (Experiment 1) or compare the power of two words presented in pairs (Experiment 2). The power distance was indexed by the absolute difference of power ratings. Results demonstrated that reaction time decreased with the power distance, whereas accuracy increased with the power distance. The findings indicated that different levels of power were presented as different vertical heights, implying that there was a common mechanism underlying space and power cognition. Copyright © 2015 Elsevier Inc. All rights reserved.

The electric power engineering handbook power systems

CERN Document Server

2012-01-01

Power Systems, Third Edition (part of the five-volume set, The Electric Power Engineering Handbook) covers all aspects of power system protection, dynamics, stability, operation, and control. Under the editorial guidance of L.L. Grigsby, a respected and accomplished authority in power engineering, and section editors Andrew Hanson, Pritindra Chowdhuri, Gerry Sheble, and Mark Nelms, this carefully crafted reference includes substantial new and revised contributions from worldwide leaders in the field. This content provides convenient access to overviews and detailed information on a diverse arr

Power electronics and control for wind power systems

DEFF Research Database (Denmark)

Iov, Florin; Blaabjerg, Frede

2009-01-01

energy at the end-user should be set up. Deregulation of energy has lowered the investment in larger power plants, which means the need for new electrical power sources may be increased in the near future. Two major technologies will play important roles to solve the future problems. One is to change......The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity. It is expected that it has to be doubled within 20 years. The production, distribution and use of the energy should be as technological efficient as possible and incentives to save...... the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. Another is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most emerging...

Normative Power

DEFF Research Database (Denmark)

's normative power than any other academic journal, including a special issue on "What Kind of Power?" in 2006. As the leading journal in the debate, this special issue brings together seven normative power articles published in JEPP since the 2006 special issue, together with Ian Manners' ‘Normative power......The social sciences have many different understandings of ‘normative power', but in European Union (EU) studies normative power has three particular meanings. The first meaning of normative power is its emphasis on normative theory, that is, how we judge and justify truth claims in social science...... effects of EU relations with the world in areas ranging from inter-regional relations, through traditional diplomacy, to environmental politics. Research areas of particular interest include the study of the interplay between physical, material and normative forms of power, as well as the constitutive...

Agent-based power sharing scheme for active hybrid power sources

Science.gov (United States)

Jiang, Zhenhua

The active hybridization technique provides an effective approach to combining the best properties of a heterogeneous set of power sources to achieve higher energy density, power density and fuel efficiency. Active hybrid power sources can be used to power hybrid electric vehicles with selected combinations of internal combustion engines, fuel cells, batteries, and/or supercapacitors. They can be deployed in all-electric ships to build a distributed electric power system. They can also be used in a bulk power system to construct an autonomous distributed energy system. An important aspect in designing an active hybrid power source is to find a suitable control strategy that can manage the active power sharing and take advantage of the inherent scalability and robustness benefits of the hybrid system. This paper presents an agent-based power sharing scheme for active hybrid power sources. To demonstrate the effectiveness of the proposed agent-based power sharing scheme, simulation studies are performed for a hybrid power source that can be used in a solar car as the main propulsion power module. Simulation results clearly indicate that the agent-based control framework is effective to coordinate the various energy sources and manage the power/voltage profiles.

Power in Bourdieu and Foucault: considerations about symbolic power and disciplinary power

Directory of Open Access Journals (Sweden)

Tiago Barros Rosa

2017-06-01

Full Text Available This article aims to present some of conceptions about power, which are present in the thoughts of two contemporary classics from Social Science: Pierre Bourdieu and Michel Foucault. Most specifically, we will analyze the foundations of the notions of symbolic power and disciplinary power, developed, respectively, on their work. Despite the theoretical and methodological differences in both authors, we attend to approach the distinct notions of power in their scientific projects and to confront them to the currently dominant tendency, whose fundamental assumption are supported by the Weberian theory. The idea of imposition of will, as discussed in Weber’s classic formulation of power, brings in itself, indelibly, the awareness, calculation and intentionality by the social actors. Both Foucault and Bordieu, the individuals - subjects and social agents – are conditioned and constrained by external relation and forces, which are often not consciously perceived.

Integrating wind power in the (French) power system

International Nuclear Information System (INIS)

Pellen, A.

2007-03-01

RTE and EDF have no other technological option than to restrain the contribution of the French wind power fleet to base-load generation where it comes in direct competition with the nuclear power plants. The author aims to explain this situation and answer the following questions. Why the fossil fueled reactor fleet in France will not be affected by an evolution of the wind power capacity? Why, in France electric power generation-demand SYSTEM wind power cannot be a substitute for fossil fueled thermal units? (A.L.B.)

Power quality in power systems and electrical machines

CERN Document Server

Fuchs, Ewald

2015-01-01

The second edition of this must-have reference covers power quality issues in four parts, including new discussions related to renewable energy systems. The first part of the book provides background on causes, effects, standards, and measurements of power quality and harmonics. Once the basics are established the authors move on to harmonic modeling of power systems, including components and apparatus (electric machines). The final part of the book is devoted to power quality mitigation approaches and devices, and the fourth part extends the analysis to power quality solutions for renewable

Adaptive Reactive Power Control of PV Power Plants for Improved Power Transfer Capability under Ultra-Weak Grid Conditions

DEFF Research Database (Denmark)

Yang, Dongsheng; Wang, Xiongfei; Liu, Fangcheng

2018-01-01

with the unity power factor. Then, considering the reactive power compensation from PV inverters, the minimum SCR in respect to Power Factor (PF) is derived, and the optimized coordination of the active and reactive power is exploited. It is revealed that the power transfer capability of PV power plant under...... of a 200 MW PV power plant demonstrate that the proposed method can ensure the rated power transfer of PV power plant with the SCR of 1.25, provided that the PV inverters are operated with the minimal PF=0.9.......This paper analyzes the power transfer limitation of the PV power plant under the ultra-weak grid condition, i.e., when the Short-Circuit Ratio (SCR) is close to 1. It explicitly identifies that a minimum SCR of 2 is required for the PV power plant to deliver the rated active power when operating...

Control of power plants and power systems. Proceedings

International Nuclear Information System (INIS)

Canales-Ruiz, R.

1996-01-01

The 88 papers in this volume constitute the proceedings of the International Federation of Automatic Control Symposium held in Mexico in 1995. The broad areas which they cover are: self tuning control; power plant operations; dynamic stability; fuzzy logic applications; power plants modelling; artificial intelligence applications; power plants simulation; voltage control; control of hydro electric units; state estimation; fault diagnosis and monitoring systems; system expansion and operation planning; security assessment; economic dispatch and optimal load flow; adaptive control; distribution; transient stability and preventive control; modelling and control of nuclear plant; knowledge data bases for automatic learning methods applied to power system dynamic security assessment; control of combined cycle units; power control centres. Separate abstracts have been prepared for the three papers relating to nuclear power plants. (UK)

The development of Chinese power industry and its nuclear power

International Nuclear Information System (INIS)

Zhou Dabin

2002-01-01

The achievements and disparity of Chinese power industry development is introduced. The position and function of nuclear power in Chinese power industry is described. Nuclear power will play a role in ensuring the reliable and safe supply of primary energy in a long-term and economic way. The development prospects of power source construction in Chinese power industry is presented. Challenge and opportunity in developing nuclear power in China are discussed

Emergency power systems at nuclear power plants

International Nuclear Information System (INIS)

1991-01-01

This Safety Guide was prepared as part of the Nuclear Safety Standards programme for establishing Codes and Safety Guides relating to nuclear power plants (NPPs). The first edition of the present Safety Guide was developed in the early 1980s. The text has now been brought up-to-date, refined in several details and amended to include non-electrical diverse and independent power sources. This Guide applies to NPP for which the total power supply comprises a normal power supply and an emergency power supply (EPS), which may be electrical or a combination of electrical and non-electrical. The Guide provides general guidance for all types of EPS and specific guidance on the design safety requirements and the features of the electrical and non-electrical portions of the EPS. 9 figs, 2 tabs

Space solar power for powering a space elevator

Energy Technology Data Exchange (ETDEWEB)

Laubscher, B. E. (Bryan E.); Kellum, M. J. (Mervyn J.)

2004-01-01

The Space Elevator (SE) represents a major paradigm shift in space access. If the SE's promise of low cost access can be realized, everything becomes economically more feasible to accomplish in space. In this paper we describe a Space Solar Power (SSP) system capable of powering the climbers of an SE. The initial SE will use laser power beaming from floating platforms near the SE platform. This study outlines an SSP system, based near the SE at geosynchronous altitude (GEO), which powers the climbers traversing the elevator. Such a system would reduce the SE system's dependence on fuel supply from land for its power beaming facilities. Moreover, since deploying SSP systems is anticipated to be a major use for SE's, SSP's could represent an elegant solution to the problem of SE energy consumption. SSP systems for sending usable power to Earth have been designed for well over 30 years. Technologies pertinent to SSP systems are continually evolving. This slightly different application carries the added requirements of aiming the beamed power at a moving target and sending the power in a form the climbers can use. Systems considered include beaming power to the climbers directly from a traditional SSP and reflecting sunlight onto the climbers. One of our designs includes a very new technology, optical rectennas. Mars SEs are conceived as having space-based power systems. Therefore, it is important to consider the problems that will be encountered in these types of applications.

high power facto high power factor high power factor hybrid rectifier

African Journals Online (AJOL)

eobe

increase in the number of electrical loads that some kind of ... components in the AC power system. Thus, suppl ... al output power; assuring reliability in ... distribution systems. This can be ...... Thesis- Califonia Institute of Technology, Capitulo.

O Electromagnetic Power Waves and Power Density Components.

Science.gov (United States)

Petzold, Donald Wayne

1980-12-01

On January 10, 1884 Lord Rayleigh presented a paper entitled "On the Transfer of Energy in the Electromagnetic Field" to the Royal Society of London. This paper had been authored by the late Fellow of Trinity College, Cambridge, Professor J. H. Poynting and in it he claimed that there was a general law for the transfer of electromagnetic energy. He argued that associated with each point in space is a quantity, that has since been called the Poynting vector, that is a measure of the rate of energy flow per unit area. His analysis was concerned with the integration of this power density vector at all points over an enclosing surface of a specific volume. The interpretation of this Poynting vector as a true measure of the local power density was viewed with great skepticism unless the vector was integrated over a closed surface, as the development of the concept required. However, within the last decade or so Shadowitz indicates that a number of prominent authors have argued that the criticism of the interpretation of Poynting's vector as a local power density vector is unjustified. The present paper is not concerned with these arguments but instead is concerned with a decomposition of Poynting's power density vector into two and only two components: one vector which has the same direction as Poynting's vector and which is called the forward power density vector, and another vector, directed opposite to the Poynting vector and called the reverse power density vector. These new local forward and reverse power density vectors will be shown to be dependent upon forward and reverse power wave vectors and these vectors in turn will be related to newly defined forward and reverse components of the electric and magnetic fields. The sum of these forward and reverse power density vectors, which is simply the original Poynting vector, is associated with the total electromagnetic energy traveling past the local point. Another vector which is the difference between the forward

Impact of advanced wind power ancillary services on power system

DEFF Research Database (Denmark)

Hansen, Anca Daniela; Altin, Müfit

The objective of this report is to illustrate and analyse, by means of simulation test cases, the impact of wind power advanced ancillary services, like inertial response (IR), power oscillation damping (POD) and synchronising power (SP) on the power system. Generic models for wind turbine, wind...... power plant and power system are used in the investigation....

Energy policy and nuclear power. Expectations of the power industry

International Nuclear Information System (INIS)

Harig, H.D.

1995-01-01

In the opinion of the power industry, using nuclear power in Germany is a responsible attitude, while opting out of nuclear power is not. Electricity utilities will build new nuclear power plants only if the structural economic and ecological advantages of nuclear power are preserved and can be exploited in Germany. The power industry will assume responsibility for new complex, capital-intensive nuclear plants only if a broad societal consensus about this policy can be reached in this country. The power industry expects that the present squandering of nuclear power resources in Germany will be stopped. The power industry is prepared to contribute to finding a speedy consensus in energy policy, which would leave open all decisions which must not be taken today, and which would not constrain the freedom of decision of coming generations. The electricity utilities remain committed proponents of nuclear power. However, what they sell to their customers is electricity, not nuclear power. (orig.) [de

Power affects performance when the pressure is on: evidence for low-power threat and high-power lift.

Science.gov (United States)

Kang, Sonia K; Galinsky, Adam D; Kray, Laura J; Shirako, Aiwa

2015-05-01

The current research examines how power affects performance in pressure-filled contexts. We present low-power-threat and high-power-lift effects, whereby performance in high-stakes situations suffers or is enhanced depending on one's power; that is, the power inherent to a situational role can produce effects similar to stereotype threat and lift. Three negotiations experiments demonstrate that role-based power affects outcomes but only when the negotiation is diagnostic of ability and, therefore, pressure-filled. We link these outcomes conceptually to threat and lift effects by showing that (a) role power affects performance more strongly when the negotiation is diagnostic of ability and (b) underperformance disappears when the low-power negotiator has an opportunity to self-affirm. These results suggest that stereotype threat and lift effects may represent a more general phenomenon: When the stakes are raised high, relative power can act as either a toxic brew (stereotype/low-power threat) or a beneficial elixir (stereotype/high-power lift) for performance. © 2015 by the Society for Personality and Social Psychology, Inc.

Ownership structure and market power in the nordic power market

International Nuclear Information System (INIS)

Amundsen, E.S.; Bergman, L.

1999-01-01

The opening of Nord Pool in 1996 seriously constrained the power companies' ability to exercise market power within their national borders. Currently there is an integration process going on among the power companies in the Nord Pool area. It manifest itself in terms of take-over and reciprocal acquisition of shares in the power companies - nationally and abroad. This process may undo what the introduction of the common power market achieved in curtailing market power. The aim of this paper is to investigate the effects on market power of increased cross- ownership in the Nordic power market. (au)

Strategic wind power trading considering rival wind power production

DEFF Research Database (Denmark)

Exizidis, Lazaros; Kazempour, Jalal; Pinson, Pierre

2016-01-01

In an electricity market with high share of wind power, it is expected that wind power producers may exercise market power. However, wind producers have to cope with wind’s uncertain nature in order to optimally offer their generation, whereas in a market with more than one wind producers, uncert...... depending on the rival’s wind generation, given that its own expected generation is not high. Finally, as anticipated, expected system cost is higher when both wind power producers are expected to have low wind power generation......In an electricity market with high share of wind power, it is expected that wind power producers may exercise market power. However, wind producers have to cope with wind’s uncertain nature in order to optimally offer their generation, whereas in a market with more than one wind producers......, uncertainty of rival wind power generation should also be considered. Under this context, this paper addresses the impact of rival wind producers on the offering strategy and profits of a pricemaker wind producer. A stochastic day-ahead market setup is considered, which optimizes the day-ahead schedules...

Custom power - the utility solution to distribution power quality

Energy Technology Data Exchange (ETDEWEB)

Woodley, N H [Westinghouse Electric Corp., Pittsburgh, PA (United States)

1997-04-01

The design of custom power products for electric power distribution system was discussed. Problems with power quality that result in loss of production to critical processes are costly and create a problem for the customer as well as the electric utility. Westinghouse has developed power quality improvement equipment for customers and utilities, using new technologies based on power electronics concepts. The Distribution Static Compensator (DSTATCOM) is a fast response, solid-state power controller that provides flexible voltage control for improving power quality at the point of connection to the utility`s 4.16 to 69 kV distribution feeder. STATCOM is a larger version of the DSTATCOM that can be used to solve voltage flicker problems caused by electric arc furnaces. Westinghouse has also developed a Dynamic Voltage Restorer (DVR) which protects a critical customer plant load from power system voltage disturbances. Solid-State Breakers (SSB) have also been developed which offer a solution to many of the distribution system problems that result in voltage sags, swells, and power outages. 6 refs., 8 figs.

On energy efficient power allocation for power-constrained systems

KAUST Repository

Sboui, Lokman

2014-09-01

Recently, the energy efficiency (EE) has become an important factor when designing new wireless communication systems. Due to economic and environmental challenges, new trends and efforts are oriented toward “green” communication especially for energy-constrained applications such as wireless sensors network and cognitive radio. To this end, we analyze the power allocation scheme that maximizes the EE defined as rate over the total power including circuit power. We derive an explicit expression of the optimal power with instantaneous channel gain based on EE criterion. We show that the relation between the EE and the spectral efficiency (SE) when the optimal power is adopted is strictly increasing in contrast with the SE-EE trade-off discussed in the literature. We also solve a non-convex problem and compute explicitly the optimal power for ergodic EE under either a peak or an average power constraint. When the instantaneous channel is not available, we provide the optimal power equation and compute simple sub-optimal power. In the numerical results, we show that the sup-optimal solution is very close to the optimal solution. In addition, we show that the absence of the channel state information (CSI) only affects the EE and the SE performances at high power regime compared to the full CSI case.

WhalePower tubercle blade power performance test report

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-15

Toronto-based WhalePower Corporation has developed turbine blades that are modeled after humpback whale flippers. The blades, which incorporate tubercles along the leading edge of the blade, have been fitted to a Wenvor 25 kW turbine installed in North Cape, Prince Edward Island at a test site for the Wind Energy Institute of Canada (WEICan). A test was conducted to characterize the power performance of the prototype wind turbine. This report described the wind turbine configuration with particular reference to turbine information, power rating, blade information, tower information, control systems and grid connections. The test site was also described along with test equipment and measurement procedures. Information regarding power output as a function of wind speed was included along with power curves, power coefficient and annual energy production. The results for the power curve and annual energy production contain a level of uncertainty. While measurements for this test were collected and analyzed in accordance with International Electrotechnical Commission (IEC) standards for performance measurements of electricity producing wind turbines (IEC 61400-12-1), the comparative performance data between the prototype WhalePower wind turbine blade and the Wenvor standard blade was not gathered to IEC data standards. Deviations from IEC-61400-12-1 procedures were listed. 6 tabs., 16 figs., 3 appendices.

Wireless Power Transmission Options for Space Solar Power

Science.gov (United States)

Potter, Seth; Davis, Dean; Born, Martin; Bayer, Martin; Howell, Joe; Mankins, John

2008-01-01

Space Solar Power (SSP), combined with Wireless Power Transmission (WPT), offers the far-term potential to solve major energy problems on Earth. In the long term, we aspire to beam energy to Earth from geostationary Earth orbit (GEO), or even further distances in space. In the near term, we can beam power over more moderate distances, but still stretch the limits of today s technology. In recent studies, a 100 kWe-class "Power Plug" Satellite and a 10 kWe-class Lunar Polar Solar Power outpost have been considered as the first steps in using these WPT options for SSP. Our current assessments include consideration of orbits, wavelengths, and structural designs to meet commercial, civilian government, and military needs. Notional transmitter and receiver sizes are considered for use in supplying 5 to 40 MW of power. In the longer term, lunar or asteroidal material can be used. By using SSP and WPT technology for near-term missions, we gain experience needed for sound decisions in designing and developing larger systems to send power from space to Earth.

Power import or domestic power generation using gas?

International Nuclear Information System (INIS)

Saettler, M.; Bohnenschaefer, W.; Schlesinger, M.

2001-01-01

This report for the Swiss Federal Office of Energy (SFOE) presents expert opinion on the question of how Switzerland could meet its demands for power in the future. The results of the analysis of two options - the import of electrical power or its generation using natural-gas-fired power stations - made in the light of gas market liberalisation are presented. These include the assessment of the use of 'GuD' (combined gas and steam-turbine) power stations in the 100 MW e l to 400 MW e l class regarding their cost, their emissions and primary energy consumption. The authors discuss the assessments from the political and economic points of view. An appendix supplies characteristic data for 'GuD' power stations and an example of a model calculation for a 400 MW e l 'GuD' power station

Power Electronics Control of Wind Energy in Distributed Power System

DEFF Research Database (Denmark)

Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

2008-01-01

is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

Nuclear power

International Nuclear Information System (INIS)

Porter, Arthur.

1980-01-01

This chapter of the final report of the Royal Commission on Electric Power Planning in Ontario updates its interim report on nuclear power in Ontario (1978) in the light of the Three Mile Island accident and presents the commission's general conclusions and recommendations relating to nuclear power. The risks of nuclear power, reactor safety with special reference to Three Mile Island and incidents at the Bruce generating station, the environmental effects of uranium mining and milling, waste management, nuclear power economics, uranium supplies, socio-political issues, and the regulation of nuclear power are discussed. Specific recommendations are made concerning the organization and public control of Ontario Hydro, but the commission concluded that nuclear power is acceptable in Ontario as long as satisfactory progress is made in the disposal of uranium mill tailings and spent fuel wastes. (LL)

Power enhancement of piezoelectric transformers for power supplies

DEFF Research Database (Denmark)

Ekhtiari, Marzieh; Steenstrup, Anders Resen; Zhang, Zhe

2016-01-01

This paper studies power enhancement of piezoelectric transformers to be used in inductorless, half-bridge, piezoelecteric-based switch mode power supplies for driving a piezo actuator motor system in a high strength magnetic environment for magnetic resonance imaging and computed tomography...... applications. A new multi element-piezo transformer solution is proposed along with a dual mode piezo transformer, providing power scaling and potentially improving the internal heat-up of a high power piezo transformer system....

Seebeck effect in (U,Pu)Osub(2+-y) and its influence on oxygen migration

International Nuclear Information System (INIS)

Annucci, F. d'; Sari, C.; Schumacher, G.; Kernforschungszentrum Karlsruhe G.m.b.H.

1979-01-01

Thermoelectric potentials have been investigated in hypo- and hyperstoichiometric uranium-plutonium mixed oxide pellets up to temperatures of 1800 K. At low temperatures, below 1200 K the Seebeck coefficient is positive. It vanishes at temperatures between 1200 K and 1800 K and changes its sign with increasing temperatures. This behavior is explained by a change of the conductivity mechanism from p- to n-type. The absolute value of the Seebeck coefficient depends strongly on the O/M-ratio. It is big for the stoichiometric region and small for higher deviations from stoichiometry. Thermoelectric power provides one of the forces which drive ions along the temperature gradients. Another force originates in the differences of the lattice forces of the various ions, atoms, and vacancies. Both forces can be described by the heat of transport of oxygen ions which contains a thermoelectric and a thermic part. The parts are calculated using the known values of the overall heat of transport and that of the measured Seebeck coefficient. (orig./HP) [de

Fábrica «Lignospan», en Inntal (Austria

Directory of Open Access Journals (Sweden)

Stigler, Willy

1965-11-01

Full Text Available This factory is devoted to the fully automatized manufacture of wood shaving slabs, and also of full and semi manufactured goods, such as doors, panels, pavements and similar. The factory comprises several naves, a store which is directly accessible from the railway, a thermic power station, a substation, and a number of accessory installations; wood storing facilities, steam chambers, and water deposits. The style and aesthetic quality are very much in the modern trend.Dedicada a la fabricación totalmente automática de placas a base de viruta, así como de diversos artículos manufacturados o semimanufacturados, tales como puertas, paneles, pavimentos, etc., este conjunto fabril comprende: varias naves, un almacén con acceso directo desde las vías del ferrocarril, central termoeléctrica, subestación eléctrica, y una serie de instalaciones secundarias: depósitos de maderas, cámaras de vapor, depósito de agua, etc. Su línea y concepto estético responden a una acertada directriz de vanguardia en arquitectura industrial.

I boschi dei Colli Berici

OpenAIRE

Tasinazzo, Stefano; Fiorentin, Roberto

2017-01-01

THE WOOD COENOSES OF COLLI SERICI (VICENZA, NE lTALY). The syntaxonomical, chorological and ecological features of the wood coenoses occurring in the hilly area of Colli Berici (Vicenza, North-Eastern Italy) are described. Three associations are recognized: the suboceanic Omithogalo pyrenaici-Carpinetum Marincek et al. 1983, Buglossoido-Ostryetum Gerdol et al. 1982 em. Poldini 1988, which prefers more marked thermic excursions, and the synanthropical Lamio orvalae-Sambucetum nigrae Poldini 19...

When power does not corrupt: superior individuation processes among powerful perceivers.

Science.gov (United States)

Overbeck, J R; Park, B

2001-10-01

To examine whether powerful people fail to individuate the less powerful, the authors assigned participants to either a high-power or low-power role for a computer E-mail role play. In 3 studies, participants in the high-power role made decisions and determined the outcomes of interactions; low-power role players had no power and relied on high-power targets for outcome decisions. Studies I and 2 found that high-power perceivers better individuated low-power targets. Study 3 demonstrated that high-power role players' superior judgment can be impaired by including a task that directs their responsibility toward organizational rather than interpersonal concerns. In all, results suggest that the effect of power on social judgment may be more complex and multifaceted than has previously been acknowledged.

Hydro power flexibility for power systems with variable renewable energy sources: an IEA Task 25 collaboration: Hydro power flexibility for power systems

Energy Technology Data Exchange (ETDEWEB)

Huertas-Hernando, Daniel [Department of Energy Systems, SINTEF, Trondheim Norway; Farahmand, Hossein [Department of Electric Power Engineering, Norwegian University of Science and Technology (NTNU), Trondheim Norway; Holttinen, Hannele [Department of Energy Systems, VTT Technical Research Centre of Finland, Espoo Finland; Kiviluoma, Juha [Department of Energy Systems, VTT Technical Research Centre of Finland, Espoo Finland; Rinne, Erkka [Department of Energy Systems, VTT Technical Research Centre of Finland, Espoo Finland; Söder, Lennart [Department of Electrical Engineering, KTH University, Stockholm Sweden; Milligan, Michael [Transmission and Grid Integration Group, National Renewable Energy Laboratory' s National Wind Technology Center, Golden CO USA; Ibanez, Eduardo [Transmission and Grid Integration Group, National Renewable Energy Laboratory' s National Wind Technology Center, Golden CO USA; Martínez, Sergio Martín [Department of Electrical Engineering, Electronics, Automation and Communications, Universidad de Castilla-La Mancha, Albacete Spain; Gomez-Lazaro, Emilio [Department of Electrical Engineering, Electronics, Automation and Communications, Universidad de Castilla-La Mancha, Albacete Spain; Estanqueiro, Ana [National Laboratory of Energy and Geology - LNEG, Lisbon Portugal; Rodrigues, Luis [National Laboratory of Energy and Geology - LNEG, Lisbon Portugal; Carr, Luis [Research Association for Energy Economics (FfE GmbH), Munich Germany; van Roon, Serafin [Research Association for Energy Economics (FfE GmbH), Munich Germany; Orths, Antje Gesa [Energinet.dk, Fredericia Denmark; Eriksen, Peter Børre [Energinet.dk, Fredericia Denmark; Forcione, Alain [Hydro Quebec, Montréal Canada; Menemenlis, Nickie [Hydro Quebec, Montréal Canada

2016-06-20

Hydro power is one of the most flexible sources of electricity production. Power systems with considerable amounts of flexible hydro power potentially offer easier integration of variable generation, e.g., wind and solar. However, there exist operational constraints to ensure mid-/long-term security of supply while keeping river flows and reservoirs levels within permitted limits. In order to properly assess the effective available hydro power flexibility and its value for storage, a detailed assessment of hydro power is essential. Due to the inherent uncertainty of the weather-dependent hydrological cycle, regulation constraints on the hydro system, and uncertainty of internal load as well as variable generation (wind and solar), this assessment is complex. Hence, it requires proper modeling of all the underlying interactions between hydro power and the power system, with a large share of other variable renewables. A summary of existing experience of wind integration in hydro-dominated power systems clearly points to strict simulation methodologies. Recommendations include requirements for techno-economic models to correctly assess strategies for hydro power and pumped storage dispatch. These models are based not only on seasonal water inflow variations but also on variable generation, and all these are in time horizons from very short term up to multiple years, depending on the studied system. Another important recommendation is to include a geographically detailed description of hydro power systems, rivers' flows, and reservoirs as well as grid topology and congestion.

The Pervasive Power of PowerPoint

DEFF Research Database (Denmark)

Schoeneborn, Dennis

2013-01-01

This paper examines the pervasive role of Microsoft’s presentation software PowerPoint as a genre of professional and organizational communication. Frequently, PowerPoint is not only used for the primary function it was initially designed for, i.e., facilitating live presentations, but also...... for alternative purposes such as project documentation. Its application in a neighboring domain, however, poses a functional dilemma: does the PowerPoint genre preserve the features of its primary function, i.e., presentation, or rather adapt to the new function, i.e., documentation? By drawing on a communication......-centered perspective, this paper examines PowerPoint’s role in the domain of project documentation as a clash between the constitutive affordances of professional and of organizational communication. To investigate this issue empirically, I conducted a case study at a multinational business consulting firm. The study...

Power fluctuation reduction methodology for the grid-connected renewable power systems

Science.gov (United States)

Aula, Fadhil T.; Lee, Samuel C.

2013-04-01

This paper presents a new methodology for eliminating the influence of the power fluctuations of the renewable power systems. The renewable energy, which is to be considered an uncertain and uncontrollable resource, can only provide irregular electrical power to the power grid. This irregularity creates fluctuations of the generated power from the renewable power systems. These fluctuations cause instability to the power system and influence the operation of conventional power plants. Overall, the power system is vulnerable to collapse if necessary actions are not taken to reduce the impact of these fluctuations. This methodology aims at reducing these fluctuations and makes the generated power capability for covering the power consumption. This requires a prediction tool for estimating the generated power in advance to provide the range and the time of occurrence of the fluctuations. Since most of the renewable energies are weather based, as a result a weather forecast technique will be used for predicting the generated power. The reduction of the fluctuation also requires stabilizing facilities to maintain the output power at a desired level. In this study, a wind farm and a photovoltaic array as renewable power systems and a pumped-storage and batteries as stabilizing facilities are used, since they are best suitable for compensating the fluctuations of these types of power suppliers. As an illustrative example, a model of wind and photovoltaic power systems with battery energy and pumped hydro storage facilities for power fluctuation reduction is included, and its power fluctuation reduction is verified through simulation.

14 CFR 27.695 - Power boost and power-operated control system.

Science.gov (United States)

2010-01-01

... Systems § 27.695 Power boost and power-operated control system. (a) If a power boost or power-operated... failure of all engines. (b) Each alternate system may be a duplicate power portion or a manually operated... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Power boost and power-operated control...

14 CFR 29.695 - Power boost and power-operated control system.

Science.gov (United States)

2010-01-01

... Systems § 29.695 Power boost and power-operated control system. (a) If a power boost or power-operated... failure of all engines. (b) Each alternate system may be a duplicate power portion or a manually operated... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Power boost and power-operated control...

POSSPOW: Possible Power of Offshore Wind Power Plants

DEFF Research Database (Denmark)

Giebel, Gregor; Göçmen, Tuhfe; Sørensen, Poul Ejnar

2013-01-01

Introduction In recent years, the very large offshore wind farms were designed as wind power plants, including possibilities to contribute to the stability of the grid by offering grid services (also called ancillary services). One of those services is reserve power, which is achieved by down......-regulating the wind farm from its maximum possible power. The power can be ramped up quite quickly, but the influence of wakes makes it difficult to assess the exact amount of down-regulation available to sell. Currently, Transmission System Operators (TSOs) have no real way to determine exactly the possible power...... will be verified on some of the large offshore wind farms owned by Vattenfall, and possibly in a DONG Energy wind farm too. Dedicated experiments to the wind flow in large offshore wind farms are planned. Main body of abstract Modern wind turbines have a SCADA signal called possible power. In normal operation...

Reactive Power Pricing Model Considering the Randomness of Wind Power Output

Science.gov (United States)

Dai, Zhong; Wu, Zhou

2018-01-01

With the increase of wind power capacity integrated into grid, the influence of the randomness of wind power output on the reactive power distribution of grid is gradually highlighted. Meanwhile, the power market reform puts forward higher requirements for reasonable pricing of reactive power service. Based on it, the article combined the optimal power flow model considering wind power randomness with integrated cost allocation method to price reactive power. Meanwhile, considering the advantages and disadvantages of the present cost allocation method and marginal cost pricing, an integrated cost allocation method based on optimal power flow tracing is proposed. The model realized the optimal power flow distribution of reactive power with the minimal integrated cost and wind power integration, under the premise of guaranteeing the balance of reactive power pricing. Finally, through the analysis of multi-scenario calculation examples and the stochastic simulation of wind power outputs, the article compared the results of the model pricing and the marginal cost pricing, which proved that the model is accurate and effective.

Power system stabilization by SMES using current-fed pwm power conditioner

International Nuclear Information System (INIS)

Ishikawa, T.; Akita, S.; Taniguchi, H.; Kosho, S.; Tanaka, T.

1988-01-01

A superconducting magnetic energy storage (SMES) unit, consisted of superconducting coil and AC/DC power conditioner, can be used to suppress various kinds of instability that may cause service interruption in electric power system as it has high controllability of input/output electric power. Power system stabilizing ability of SMES has been examined experimentally by using model power system and small SMES unit. Current-fed PWM power conditioner was used to obtain maximum stabilizing effect by controlling active and reactive power simultaneously and independently. Power conditioner configuration, operating characteristics and control scheme for power system stabilization are also described. Results from experiments show the effectiveness of SMES on power system stabilization

7 CFR 1710.303 - Power cost studies-power supply borrowers.

Science.gov (United States)

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Power cost studies-power supply borrowers. 1710.303... AND GUARANTEES Long-Range Financial Forecasts § 1710.303 Power cost studies—power supply borrowers. (a... facilities shall be supported by a power cost study to demonstrate that the proposed generation and...

Nuclear power. Volume 2. Nuclear power project management

International Nuclear Information System (INIS)

Pedersen, E.S.

1978-01-01

NUCLEAR POWER PLANT DESIGN is intended to be used as a working reference book for management, engineers and designers, and as a graduate-level text for engineering students. The book is designed to combine theory with practical nuclear power engineering and design experience, and to give the reader an up-to-date view of the status of nuclear power and a basic understanding of how nuclear power plants function. Volume 2 contains the following chapters: (1) review of nuclear power plants; (2) licensing procedures; (3) safety analysis; (4) project professional services; (5) quality assurance and project organization; (6) construction, scheduling, and operation; (7) nuclear fuel handling and fuel management; (8) plant cost management; and (9) conclusion

Power in Households: Disentangling Bargaining Power

NARCIS (Netherlands)

R. Mabsout (Ramzi); I.P. van Staveren (Irene)

2009-01-01

textabstractIntroduction Within the household bargaining literature, bargaining power is generally understood in terms of economic resources, such as income or assets. Empirical analyses of women’s bargaining power in households in developed and developing countries find that, in general, higher

Power corrupts

International Nuclear Information System (INIS)

Bacon, H.; Valentine, J.

1981-01-01

The subject is covered in chapters, entitled: radiation (hazards associated with nuclear power production); wastes (radioactive wastes); accidents (actual and postulated, resulting in the release of radiation); the FBR and the plutonium cycle; costs (economics of nuclear power); spent fuel transport; civil liberties; doing without nuclear power (UK power demand; low energy strategy; energy policy; government policies; alternative energy sources). (U.K.)

Power control of the Angra-2 Nuclear Power Plant

International Nuclear Information System (INIS)

Souza Mendes, J.E. de

1986-01-01

The systems for the power control of the Nuclear Power Plant Angra 2 have a high degree of automation so that few operator actions are required during power operation. The power control strategy and the operation principles of the control systems, here presented, make possible a great flexibility of the Plant operation. (Author) [pt

Calculation of Wind Power Limit adjusting the Continuation Power Flow

International Nuclear Information System (INIS)

Santos Fuentefria, Ariel; Castro Fernández, Miguel; Martínez García, Antonio

2012-01-01

The wind power insertion in the power system is an important issue and can create some instability problems in voltage and system frequency due to stochastic origin of wind. Know the Wind Power Limit is a very important matter. Existing in bibliography a few methods for calculation of wind power limit. The calculation is based in static constrains, dynamic constraints or both. In this paper is developed a method for the calculation of wind power limit using some adjust in the continuation power flow, and having into account the static constrains. The method is complemented with Minimal Power Production Criterion. The method is proved in the Isla de la Juventud Electric System. The software used in the simulations was the Power System Analysis Toolbox (PSAT). (author)

Reactor power control method upon accidents of electrical power system

International Nuclear Information System (INIS)

Hirose, Masao.

1983-01-01

Purpose: To enable to continue the operation of a BWR type reactor by avoiding the scram while suppressing the reactor power, just after the external disturbance such as earth-trouble in power-transmission network. Method: Steep power drop of an electrical generator is to be detected not only by a current-type power-load-unbalance relay but also with a power-type power-load-unbalance-relay. If steep power-drop was detected by the latter relay, a previously selected control rod is rapidly inserted into the reactor. In this way, in the case where there is a possibility of the reactor scram, the scram can be avoided by suppressing the reactor power, thus the reactor operation can be continued. (Kamimura, M.)

Possible Power Estimation of Down-Regulated Offshore Wind Power Plants

DEFF Research Database (Denmark)

Gögmen, Tuhfe

The penetration of offshore wind power is continuously increasing in the Northern European grids. To assure safety in the operation of the power system, wind power plants are required to provide ancillary services, including reserve power attained through down-regulating the wind farm from its...... power plant. The developed procedure, the PossPOW algorithm, can also be used in the wind farm control as it yields a real-time wind farm power curve. The modern wind turbines have a possible power signal at the turbine level and the current state of the art is to aggregate those signals to achieve...... the wind farm scale production capacity. However the summation of these individual signals is simply an over-estimation for the wind power plant, due to reduced wake losses during curtailment. The determination of the possible power with the PossPOW algorithm works as follows: firstly the second...

Research Developments on Power System Integration of Wind Power

DEFF Research Database (Denmark)

Chen, Zhe; Hansen, Jens Carsten; Wu, Qiuwei

2011-01-01

variability and prediction, wind power plant ancillary services, grid connection and operation, Smart grids and demand side management under market functionality. The topics of the first group of PhD program starting 2011 under the wind energy Sino-Danish Centre for Education & Research (SDC) are also......This paper presents an overview on the recent research activities and tendencies regarding grid integration of wind power in Denmark and some related European activities, including power electronics for enhancing wind power controllability, wind turbines and wind farms modeling, wind power...

Power, stability of power, and creativity

NARCIS (Netherlands)

Sligte, Daniel J.; de Dreu, Carsten K. W.; Nijstad, Bernard A.

Power hierarchies are an essential aspect of social organization, create stability and social order, and provide individuals with incentives to climb the hierarchical ladder. Extending previous work on power and creativity, we put forward that this relationship critically depends on both the

Power, stability of power, and creativity

NARCIS (Netherlands)

Sligte, D.J.; de Dreu, C.K.W.; Nijstad, B.A.

2011-01-01

Power hierarchies are an essential aspect of social organization, create stability and social order, and provide individuals with incentives to climb the hierarchical ladder. Extending previous work on power and creativity, we put forward that this relationship critically depends on both the

Power quality load management for large spacecraft electrical power systems

Science.gov (United States)

Lollar, Louis F.

1988-01-01

In December, 1986, a Center Director's Discretionary Fund (CDDF) proposal was granted to study power system control techniques in large space electrical power systems. Presented are the accomplishments in the area of power system control by power quality load management. In addition, information concerning the distortion problems in a 20 kHz ac power system is presented.

The electric power engineering handbook power system stability and control

CERN Document Server

Grisby, Leonard L

2012-01-01

With contributions from worldwide leaders in the field, Power System Stability and Control, Third Edition (part of the five-volume set, The Electric Power Engineering Handbook) updates coverage of recent developments and rapid technological growth in essential aspects of power systems. Edited by L.L. Grigsby, a respected and accomplished authority in power engineering, and section editors Miroslav Begovic, Prabha Kundur, and Bruce Wollenberg, this reference presents substantially new and revised content. Topics covered include: * Power System Protection * Power System Dynamics and Stability *

Self-powered detectors for power reactors: an overview

International Nuclear Information System (INIS)

Ma, J.

2006-01-01

In this paper, Self-Powered Detectors (SPDs) for applications in nuclear power reactors have been reviewed. Based on their responses to radiation, these detectors can be divided into delayed response Self-Powered Neutron Detector (SPND), prompt response SPND and Self-Powered Gamma Detector (SPGD). The operational principles of these detectors are presented and their distinctive characteristics are examined accordingly. The analytical models and Monte Carlo method to calculate the responses of these detectors to neutron flux and external gamma rays are reviewed. The paper has also considered some related signal processing techniques, such as detector calibrations and detector signal compensations. Furthermore, a couple of failure modes have also been analyzed. Finally, applications of SPD in nuclear power reactors are summarized. (author)

Nuclear power. Volume 1. Nuclear power plant design

International Nuclear Information System (INIS)

Pedersen, E.S.

1978-01-01

NUCLEAR POWER PLANT DESIGN is intended to be used as a working reference book for management, engineers and designers, and as a graduate-level text for engineering students. The book is designed to combine theory with practical nuclear power engineering and design experience, and to give the reader an up-to-date view of the status of nuclear power and a basic understanding of how nuclear power plants function. Volume 1 contains the following chapters; (1) nuclear reactor theory; (2) nuclear reactor design; (3) types of nuclear power plants; (4) licensing requirements; (5) shielding and personnel exposure; (6) containment and structural design; (7) main steam and turbine cycles; (8) plant electrical system; (9) plant instrumentation and control systems; (10) radioactive waste disposal (waste management) and (11) conclusion

Self-powered detectors for power reactors: an overview

Energy Technology Data Exchange (ETDEWEB)

Ma, J. [Univ. of Western Ontario, Dept. of Mechanical and Materials Engineering, London, Ontario (Canada)]. E-mail: jma64@uwo.ca

2006-07-01

In this paper, Self-Powered Detectors (SPDs) for applications in nuclear power reactors have been reviewed. Based on their responses to radiation, these detectors can be divided into delayed response Self-Powered Neutron Detector (SPND), prompt response SPND and Self-Powered Gamma Detector (SPGD). The operational principles of these detectors are presented and their distinctive characteristics are examined accordingly. The analytical models and Monte Carlo method to calculate the responses of these detectors to neutron flux and external gamma rays are reviewed. The paper has also considered some related signal processing techniques, such as detector calibrations and detector signal compensations. Furthermore, a couple of failure modes have also been analyzed. Finally, applications of SPD in nuclear power reactors are summarized. (author)

Nuclear Power

International Nuclear Information System (INIS)

Douglas-Hamilton, J.; Home Robertson, J.; Beith, A.J.

1987-01-01

In this debate the Government's policy on nuclear power is discussed. Government policy is that nuclear power is the safest and cleanest way of generating electricity and is cheap. Other political parties who do not endorse a nuclear energy policy are considered not to be acting in the people's best interests. The debate ranged over the risks from nuclear power, the UK safety record, safety regulations, and the environmental effects of nuclear power. The Torness nuclear power plant was mentioned specifically. The energy policy of the opposition parties is strongly criticised. The debate lasted just over an hour and is reported verbatim. (UK)

Reactive power management of power networks with wind generation

CERN Document Server

Amaris, Hortensia; Ortega, Carlos Alvarez

2012-01-01

As the energy sector shifts and changes to focus on renewable technologies, the optimization of wind power becomes a key practical issue. Reactive Power Management of Power Networks with Wind Generation brings into focus the development and application of advanced optimization techniques to the study, characterization, and assessment of voltage stability in power systems. Recent advances on reactive power management are reviewed with particular emphasis on the analysis and control of wind energy conversion systems and FACTS devices. Following an introduction, distinct chapters cover the 5 key

Wind power and the conditions at a liberalized power market

International Nuclear Information System (INIS)

Morthorst, P.E.

2003-01-01

Wind power is undergoing a rapid development nationally as well as globally and in a number of countries covers an increasing part of the power supply. At the same time an ongoing liberalization of power markets is taking place and to an increasing extent the owners of wind power plants will themselves have to be responsible for trading the power at the spot market and financially handling the balancing. In the western part of Denmark (Jutland/Funen area), wind-generated power from time to time covers almost 100% of total power consumption. Therefore some examples are chosen from this area to analyse in more detail how well large amounts of wind power in the short-term are handled at the power spot market. It turns out that there is a tendency that more wind power in the system in the short run leads to relatively lower spot prices, while less wind power implies relatively higher spot prices, although, with the exception of December 2002, in general no strong relationship is found. A stronger relationship is found at the regulating market, where there is a fairly clear tendency that the more wind power produced, the higher is the need for down-regulation, and, correspondingly, the less wind power produced, the higher is the need for up-regulation. In general for the Jutland/Funen area the average cost of down-regulation is calculated as 1 2 c euros/kWh regulated for 2002, while the cost of up-regulation amounts to 0 7 c euros/kWh regulated. (author)

Operating modes and practical power flow analysis of bidirectional isolated power interface for distributed power systems

International Nuclear Information System (INIS)

Wen, Huiqing; Su, Bin

2016-01-01

Highlights: • Four operating modes of Dual-Phase-Shift control for Dual Active Bridge converter are presented. • Effects of “minor parameters” such as the deadtime and power device voltage drops are analyzed. • Accurate power flow models with Dual-Phase-Shift control are developed and verified with experimental results. • Optimal operating mode is determined with respect to the efficiency improvement. • Measured efficiency of the Dual Active Bridge converter is improved up to 14%. - Abstract: Due to the intermittent nature of the renewable energy sources including photovoltaic and wind energy, the energy storage systems are essential to stabilize dc bus voltage. Considering the discharge depth of super-capacitors and energy-storage batteries, the bidirectional isolated power interface will operate for a wide range of voltage and power. This study focuses on in-depth analysis of the dual-active-bridge dc–dc converter that is controlled by the dual-phase-shift scheme to improve the conversion efficiency in distributed power system. The power flow of each operating mode with dual-phase-shift control is characterized based on a detailed analysis of the effects of “minor parameters”, including the deadtime and power device voltage drops. The complete output power plane of the dual-active-bridge converter with dual-phase-shift control is obtained and compared with experimental results. The optimal operating mode is determined according to the practical output power range and the power flow characteristics. Experimental evaluation shows the effectiveness of the proposed power flow model with dual-phase-shift control and significant efficiency improvement using the optimal mode of dual-phase-shift compared with the conventional phase shift control.

Power and revenge.

Science.gov (United States)

Strelan, Peter; Weick, Mario; Vasiljevic, Milica

2014-09-01

We took an individual differences approach to explain revenge tendencies in powerholders. Across four experimental studies, chronically powerless individuals sought more revenge than chronically powerful individuals following a high power episode (Studies 1 and 2), when striking a powerful pose (Study 3), and when making a powerful hand gesture (Study 4). This relationship vanished when participants were not exposed to incidental power. A meta-analysis revealed that, relative to a lack of power or a neutral context, exposure to incidental power increased vengeance among the chronically powerless and reduced vengeance among the chronically powerful. These findings add to previous research on relations between power and aggression, and underscore the role of individual differences as a determinant of powerholders' destructive responses. © 2013 The British Psychological Society.

Power marketing

International Nuclear Information System (INIS)

Sioshansi, F.P.; Altman, A.M.

1998-01-01

One of the most significant developments in the US electric power industry in recent years has been the phenomenal growth of power marketing. What was barely a blimp on the radar screen in 1992 has turned out to be a jumbo jet. This article explains what is power marketing who are power marketers, what role play these players and what will be their longer-term impact on the traditional industry [it

Active Power Controls from Wind Power: Bridging the Gaps

Energy Technology Data Exchange (ETDEWEB)

Ela, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gevorgian, V. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Fleming, P. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Zhang, Y. C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Singh, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Muljadi, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Scholbrook, A. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Aho, J. [Univ. of Colorado, Boulder, CO (United States); Buckspan, A. [Univ. of Colorado, Boulder, CO (United States); Pao, L. [Univ. of Colorado, Boulder, CO (United States); Singhvi, V. [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Tuohy, A. [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Pourbeik, P. [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Brooks, D. [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Bhatt, N. [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States)

2014-01-01

This paper details a comprehensive study undertaken by the National Renewable Energy Laboratory, Electric Power Research Institute, and the University of Colorado to understand how the contribution of wind power providing active power control (APC) can benefit the total power system economics, increase revenue streams, improve the reliability and security of the power system, and provide superior and efficient response while reducing any structural and loading impacts that may reduce the life of the wind turbine or its components. The study includes power system simulations, control simulations, and actual field tests using turbines at NREL's National Wind Technology Center (NWTC). The study focuses on synthetic inertial control, primary frequency control, and automatic generation control, and analyzes timeframes ranging from milliseconds to minutes to the lifetime of wind turbines, locational scope ranging from components of turbines to large wind plants to entire synchronous interconnections, and additional topics ranging from economics to power system engineering to control design.

Analysis by neutronic activation of samples of a geologic formation of Cuba

International Nuclear Information System (INIS)

Capote Rodriguez, G.; Pena Fortes, B.; Padilla Alvarez, R.; Llanes Castro, A.I.; Perez Zayas, G.; Hernandez Rivero, A.T.; Lopez Reyes, M. C.; Ribeiro Guevara, S.; Molina Insfran, J.

1997-01-01

The analysis by neutronic activation (AAN) is an analytical non destructive technique of high accuracy and sensibility. These advantages are very utilized in the determination of geological multielemental samples. In the job 22 elements are determined in 9 geological samples pertaining to the complex of dams of acid composition that includes the graphitic micaceous schist and the quartzites of the Canada Formation, developed fundamentally in the fasteners of the anticlinal Victoria (Yac. of Wolframio Lela, Island of the Youth, Cuba) The results obtained are of great importance for the evaluation of the potentiality of these rocks as fountains or of uranium adjusting and for the geologic prognostic of the region in study. The irradiation of the samples was carried out during three campaigns, in two occasions (October 1992 and November 1994) in the reactor of investigations of the ININ of Mexico, with a flow of thermic neutrons of 10a the 13 n.s -1 cm -2 and in an occasion in the nuclear reactor of the CAB (september 1994), with a flow of thermic neutrons of 6x 10 to the 12 n.s-1. The results were processed with the program ACTAM in the CEADEN. (S. Grainger) [es

Minimum critical power ratio control device for nuclear power plants

International Nuclear Information System (INIS)

Kurosawa, Tsuneo.

1991-01-01

Reactor core flowrate is determined by comparing a minimum critical power ratio calculated based on the status amount of a nuclear power plant and a control value for the minimum critical power ratio that depends on the reactor core flowrate. Further, the minimum critical power ratio and a control value for the minimum critical power ratio that depends on the reactor thermal power are compared to set a reactor thermal power converted to a reactor core flowrate. Deviation between the thus determined reactor core flowrate and the present reactor core flowrate is calculated. When the obtained deviation is lower than a rated value, a reactor core flowrate set signal is generated to a reactor flowrate control means, to control the reactor power by a recycling flowrate control system of the reactor. On the other hand, when the deviation exceeds the determined value, the reactor core flowrate set signal is converted into a reactor thermal power, to control the position of control rods and control the reactor power. Then, monitor and control can be conducted safely and automatically without depending on operator's individual ability over the entire operation range corresponding to load following operation. (N.H.)

Efficient power supply using Power over Ethernet; Effiziente Stromversorgung mittels Power over Ethernet (PoE)

Energy Technology Data Exchange (ETDEWEB)

Huser, A.

2005-07-01

This final report for the Swiss Federal Office of Energy (SFOE) takes a look at methods of supplying small equipment such as Internet telephones, web cams, hubs, hard discs, audio equipment, point-of-sale terminals, game consoles etc. with power via their Ethernet connections. A short comparison is presented between Power over Ethernet (PoE) and other methods of supplying power along with data, including Universal Serial Bus (USB), FireWire and Powerline systems. The advantages of PoE over the use of separate power supply units are discussed and recommendations are made to the manufacturers and users of small peripheral equipment regarding the dimensioning and loading of such power supply systems.

Multi-time scale dynamics in power electronics-dominated power systems

Science.gov (United States)

Yuan, Xiaoming; Hu, Jiabing; Cheng, Shijie

2017-09-01

Electric power infrastructure has recently undergone a comprehensive transformation from electromagnetics to semiconductors. Such a development is attributed to the rapid growth of power electronic converter applications in the load side to realize energy conservation and on the supply side for renewable generations and power transmissions using high voltage direct current transmission. This transformation has altered the fundamental mechanism of power system dynamics, which demands the establishment of a new theory for power system control and protection. This paper presents thoughts on a theoretical framework for the coming semiconducting power systems.

Modelling of electrical power systems for power flow analysis

Energy Technology Data Exchange (ETDEWEB)

Cogo, Joao Roberto [Escola Federal de Engenharia de Itajuba, MG (Brazil)

1994-12-31

The industry systems in Brazil are responsible for a consumption of over 50% (fifty per cent) of the total electrical power generated: therefore, they are import loads in power flow studies, and their modeling should be as much the best. Usually, in power flow studies, the industry systems are modeled by taking the influence of the power (active and reactive) and of the current on the voltage into account. Since the inducting motors, within the industry systems, represent at least 50% (fifty per cent) of the power consumption, and a large part of them is oversize, it is proposed to represent the industry systems as a function of the characteristic of power on shaft versus voltage into account. Since the induction motors, within the industry systems, represent at least 50% (fifty per cent) of the power consumption, and a large part of them is oversized, it is proposed to represent the industry systems as a function of the characteristics of power on shaft versus voltage for the analysis of power systems, aiming a load flow study. Thereafter, a model of an equivalent motor which has a basis the typical performance curve of an induction motor is present. This model is obtained from empirical parameters, surveyed from a population of over 1000 motors. (author) 3 refs., 1 fig., 4 tabs.

With power comes responsibility: motorcycle engine power and power-to-weight ratio in relation to accident risk.

Science.gov (United States)

Mattsson, Markus; Summala, Heikki

2010-02-01

Current European legislation allows the EU member states to restrict the maximum power output of motorcycles to 74 kW even though evidence supporting the limit is scarce and has produced mixed results-perhaps because motorcycle performance has been measured by engine displacement, not engine power, in most of the previous studies. This study investigates the relationship of motorcycle engine power and power-to-weight ratio to risk of fatal and nonfatal crashes in Finland. The fatality rate (number of fatal accidents/number of registered motorbikes) for riders of different ages riding bikes belonging to different power and power-to-weight ratio classes was examined using a comprehensive in-depth database. Data on nonfatal accidents were acquired from a Web questionnaire (N = 2708), which also served as a basis for estimating riders' annual mileage. Mileage data allowed the calculation of accident risk per kilometer ridden for bikes differing in power and power-to-weight ratio. The fatality risk per number of registered motorcycles and per kilometer ridden increases both with power and power-to-weight ratio, independently of rider's age. No relationship between performance and risk of a less severe crash was found. The pre-accident speed of the most powerful bikes was 20 km/h or more over the speed limit in a large proportion of the fatal accidents (odds ratio = 4.8 for > 75 kW motorbikes; odds ratio = 6.2 for > 0.3 kW/kg motorbikes). The risk of being involved in a fatal crash is higher among the riders of powerful motorcycles. However, it is not clear whether the results are related to the riding habits of the riders that choose the most powerful bikes available or whether the high risk is due to the properties of the bikes themselves. Therefore, further research is needed before considering legal limits on motorcycle performance.

Green power programs in Canada : 2003 : overview of Government green power policies, utility green power implementation initiatives, green power and certificate marketing programs, and their benefits

International Nuclear Information System (INIS)

Whitmore, J.; Bramley, M.; Holmes, R.

2004-09-01

Green power is defined as electricity produced from renewable sources, and whose production has low adverse impacts on the environment, human health and communities. Green power has near-zero greenhouse gas (GHG) emissions and includes sources such as wind, hydro, and solar power. It offers several environmental benefits, as well as the enhancement of energy security, regional development, economic diversification and the creation of skilled jobs. There are four categories of programs related to green power development in Canada: government green power policies, utility green power development programs, green power marketing initiatives, and green power certificate marketing initiatives. Most of the activities in Canada associated with these four categories in 2003 were discussed in this report. However, difficulties with quantification prevented the inclusion of some green power activities such as (1) the generation of green power not certified or identified by the generator as green power, (2) industry or residential self-generation, (3) net metering, and (4) small government programs. Green power generation facilities in 2003 totaled 775 MW of capacity compared to 539 MW in 2002. Hydro capacity represented 41 per cent, followed by wind capacity at 40 per cent and wood waste at 17 per cent. Most of the green power generation facilities in 2003 were located in Alberta, followed by British Columbia, Ontario and Quebec. 230 refs., 8 tabs., 1 fig

Non-power application as an entry point to nuclear power program

International Nuclear Information System (INIS)

Nahrul Khair Alang Md Rashid

2009-01-01

Nuclear power is usually viewed as the flagship of nuclear technology. A nuclear power plant complex, visible and prominence, is iconic of the technology. That image makes its presence common knowledge to the extent that nuclear technology is equated almost totally with nuclear power by the general public. The downside of this visibility is that it becomes easy target in public misinformation programs. The non-power applications however are not visible, and devoid of icon. The non-power applications, therefore, can grow quite smoothly, attracting only little attention in the negative and in the positive senses. According to a study conducted in the USA in 2000 and in Japan in 2002, the socio-economic impact of non-power and power applications of nuclear technology are comparable. Involvement in non-power applications can be a good grounding for moving into power applications. This paper discusses the non-power nuclear technology applications and in what manner it can serve to prepare the introduction of nuclear power program. (Author)

Power generation

International Nuclear Information System (INIS)

Nunez, Anibal D.

2001-01-01

In the second half of twentieth century, nuclear power became an industrial reality. Now the operating 433 power plants, the 37 plants under construction, near 9000 years/reactor with only one serious accident with emission of radioactive material to the environment (Chernobyl) show the maturity of this technology. Today nuclear power contribute a 17% to the global generation and an increase of 75 % of the demand of electricity is estimated for 2020 while this demand is expected to triplicate by 2050. How this requirement can be satisfied? All the indicators seems to demonstrate that nuclear power will be the solution because of the shortage of other sources, the increase of the prices of the non renewable fuels and the scarce contribution of the renewable ones. In addition, the climatic changes produced by the greenhouse effect make even more attractive nuclear power. The situation of Argentina is analyzed and compared with other countries. The convenience of an increase of nuclear power contribution to the total national generation seems clear and the conclusion of the construction of the Atucha II nuclear power plant is recommended

Multimode power processor

Science.gov (United States)

O'Sullivan, George A.; O'Sullivan, Joseph A.

1999-01-01

In one embodiment, a power processor which operates in three modes: an inverter mode wherein power is delivered from a battery to an AC power grid or load; a battery charger mode wherein the battery is charged by a generator; and a parallel mode wherein the generator supplies power to the AC power grid or load in parallel with the battery. In the parallel mode, the system adapts to arbitrary non-linear loads. The power processor may operate on a per-phase basis wherein the load may be synthetically transferred from one phase to another by way of a bumpless transfer which causes no interruption of power to the load when transferring energy sources. Voltage transients and frequency transients delivered to the load when switching between the generator and battery sources are minimized, thereby providing an uninterruptible power supply. The power processor may be used as part of a hybrid electrical power source system which may contain, in one embodiment, a photovoltaic array, diesel engine, and battery power sources.

Credit Risk Evaluation of Large Power Consumers Considering Power Market Transaction

Science.gov (United States)

Fulin, Li; Erfeng, Xu; ke, Sun; Dunnan, Liu; Shuyi, Shen

2018-03-01

Large power users will participate in power market in various forms after power system reform. Meanwhile, great importance has always attached to the construction of the credit system in power industry. Due to the difference between the awareness of performance and the ability to perform, credit risk of power customer will emerge accordingly. Therefore, it is critical to evaluate credit risk of large power customers in the new situation of power market. Firstly, this paper constructs index system of credit risk of large power customers, and establishes evaluation model of interval number and AHP-entropy weight method.

Dynamic Influences of Wind Power on The Power System

DEFF Research Database (Denmark)

Rosas, Pedro Andrè Carvalho

2004-01-01

between different wind turbines.Here the wind speed model is applied to a constant rotational speed wind turbine/farm, but the model is suit-able to variable speed wind turbine/farm as well. The cases presented here illustrate the influences of the wind power on the power systemquality and stability...... integration due to the low spatial correlation of the wind speed. The voltage quality analysed in a Brazilian power system and in the Nordel power system from connecting largeamount of wind power showed very small voltage variations. The frequency variations analysed from the Nordel showed also small varia...

Will cross-ownership reestablish market power in the Nordic power market?

International Nuclear Information System (INIS)

Amundsen, Eirik S.; Bergman, Lars

2000-01-01

The integration of the power markets in Norway and Sweden in 1996 significantly constrained the major power companies' ability to exercise market power within their national borders. In recent years, however, mergers and reciprocal acquisition of shares have reduced the number of independent players on the Norwegian-Swedish power market. The aim of this paper is to explore to what extent increasing cross-ownership among major power companies in Norway and Sweden might re-establish the market power that was lost when the two national power markets were integrated. The analysis is based on a numerical model, assuming Cournot quantity setting behaviour, of the Norwegian-Swedish power market. The simulation results suggest that partial ownership relations between major generators and other power-producing firms tend to increase horizontal market power and thus the market price of electricity. (author)

High power fast ramping power supplies

Energy Technology Data Exchange (ETDEWEB)

Marneris,I.; Bajon, E.; Bonati, R.; Sandberg, J.; Roser, T.; Tsoupas, N.

2009-05-04

Hundred megawatt level fast ramping power converters to drive proton and heavy ion machines are under research and development at accelerator facilities in the world. This is a leading edge technology. There are several topologies to achieve this power level. Their advantages and related issues will be discussed.

Characterization of power IGBTs under pulsed power conditions

Energy Technology Data Exchange (ETDEWEB)

Dale, Gregory E [Los Alamos National Laboratory; Vangordon, James [UNIV OF MISSOURI; Kovaleski, Scott [UNIV OF MISSOURI

2009-01-01

The power insulated gate bipolar transistor (IGBT) is used in many types of applications. Although the use of the power IGBT has been well characterized for many continuous operation power electronics applications, little published information is available regarding the performance of a given IGBT under pulsed power conditions. Additionally, component libraries in circuit simulation software packages have a finite number of IGBTs. This paper presents a process for characterizing the performance of a given power IGBT under pulsed power conditions. Specifically, signals up to 3.5 kV and 1 kA with 1-10 {micro}s pulse widths have been applied to a Powerex QIS4506001 IGBT. This process utilizes least squares curve fitting techniques with collected data to determine values for a set of modeling parameters. These parameters were used in the Oziemkiewicz implementation of the Hefner model for the IGBT that is utilized in some circuit simulation software packages. After the nominal parameter values are determined, they can be inserted into the Oziemkiewicz implementation to simulate a given IGBT.

Green power programs in Canada : 2002 : Overview of Government green power policies, utility green power development programs, green power and certificate marketing initiatives, and their benefits

International Nuclear Information System (INIS)

Bramley, M.; Boustie, S.; Vadgama, J.; Wieler, C.; Pape-Salmon, A.; Holmes, R.

2003-11-01

Green power is generally defined as electricity produced from renewable sources, and whose production has low adverse impacts on the environment, human health and communities. Green power has near-zero greenhouse gas (GHG) emissions and includes sources such as wind, hydro, and solar power. Green power offers several environmental benefits, as well as the enhancement of energy security, regional development, economic diversification and the creation of skilled jobs. There are four categories of programs related to green power development in Canada: government green power policies, utility green power development programs, green power marketing initiatives, and green power certificate marketing initiatives. Most of the activities associated with these four categories in 2002 were discussed in this report. However, difficulties with quantification prevented the inclusion of some green power activities in the report, such as (1) the generation of green power not certified or identified by the generator as green power, (2) industry or residential self-generation, (3) net metering, and (4) small government programs. Each category was presented in detail. The information included in the report was based on surveys sent to each program proponent. Follow-up communications and other publicly available information was also included. New programs operating in 2003 or currently under development were listed. refs., 8 tabs

Felt power explains the link between position power and experienced emotions.

Science.gov (United States)

Bombari, Dario; Schmid Mast, Marianne; Bachmann, Manuel

2017-02-01

The approach/inhibition theory by Keltner, Gruenfeld, and Anderson (2003) predicts that powerful people should feel more positive and less negative emotions. To date, results of studies investigating this prediction are inconsistent. We fill this gap with four studies in which we investigated the role of different conceptualizations of power: felt power and position power. In Study 1, participants were made to feel more or less powerful and we tested how their felt power was related to different emotional states. In Studies 2, 3, and 4, participants were assigned to either a high or a low power role and engaged in an interaction with a virtual human, after which participants reported on how powerful they felt and the emotions they experienced during the interaction. We meta-analytically combined the results of the four studies and found that felt power was positively related to positive emotions (happiness and serenity) and negatively to negative emotions (fear, anger, and sadness), whereas position power did not show any significant overall relation with any of the emotional states. Importantly, felt power mediated the relationship between position power and emotion. In summary, we show that how powerful a person feels in a given social interaction is the driving force linking the person's position power to his or her emotional states. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Power Outages

Science.gov (United States)

... Publications Emergency Alerts Preparedness Portal Preparedness Messaging Calendar Social Media Preparedness Toolkits Preparedness News Languages About Us Build a Kit Close Search Enter Search Term(s): Main Content Home Be Informed Power Outages Power Outages Extended power outages may impact ...

Electric Vehicles in Power Systems with 50% Wind Power Penetration

DEFF Research Database (Denmark)

Østergaard, Jacob; Foosnæs, Anders; Xu, Zhao

2009-01-01

will be an important balancing measure to enable the Danish government’s energy strategy, which implies 50% wind power penetration in the electric power system. An EV will be a storage device for smoothing power fluctuations from renewable resources especially wind power and provide valuable system services...... for a reliable power system operation. Cost-benefit analysis shows that intelligent bidirectional charging – vehicle to grid (V2G) – provides a socio-economic profit of 150 million Euro/year in the Danish electric power system in 2025 assuming that 15% of the Danish road transport need is supplied by electricity....... This paper analyse the potential for using EVs in Denmark and identify the benefits of the electric power system with high wind power generation by intelligent charging of the EVs. Based on the analysis important technology gabs are identified, and the corresponding research and development initiatives...

Power control strategy of a photovoltaic power plant for microgrid applications

Energy Technology Data Exchange (ETDEWEB)

Li, Peng [Ecole Centrale de Lille, Cite Scientifique, Villeneuve d' Ascq (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP); Ecole Nationale Superieure d' Arts et Metiers, Lille (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP); Francois, Bruno [Ecole Centrale de Lille, Cite Scientifique, Villeneuve d' Ascq (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP); Degobert, Philippe [Ecole Nationale Superieure d' Arts et Metiers, Lille (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP); Robyns, Benoit [Hautes Etudes d' Ingenieur, Lille (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP)

2008-07-01

Photovoltaic power plants operates currently maximal power point tracking (MPPT). For microgrid applications, however, a PV power plant can not operate in the MPPT mode in all conditions. When a microgrid is islanded from the grid with few loads, a limitation of the produced power by PV plants is required and prescribed by the Distribution System Operator. This paper proposes a power control technique integrated into a dynamic model of a PV power plant by using equivalent continuous models of power electronic converters. The power limitation mode of the PV is performed by applying the correct PV terminal voltage, which corresponds to the prescribed power reference. The proposed global model is validated by simulations with the help of Matlab-Simulink trademark. (orig.)

How to Integrate Variable Power Source into a Power Grid

Science.gov (United States)

Asano, Hiroshi

This paper discusses how to integrate variable power source such as wind power and photovoltaic generation into a power grid. The intermittent renewable generation is expected to penetrate for less carbon intensive power supply system, but it causes voltage control problem in the distribution system, and supply-demand imbalance problem in a whole power system. Cooperative control of customers' energy storage equipment such as water heater with storage tank for reducing inverse power flow from the roof-top PV system, the operation technique using a battery system and the solar radiation forecast for stabilizing output of variable generation, smart charging of plug-in hybrid electric vehicles for load frequency control (LFC), and other methods to integrate variable power source with improving social benefits are surveyed.

Power that Builds Others and Power that Breaks: Effects of Power and Humility on Altruism and Incivility in Female Employees.

Science.gov (United States)

Yoon, David J; Farmer, Steven M

2018-01-02

Building on the approach/inhibition theory of power and the situated focus theory of power, we examine the roles of positional and personal power on altruism and incivility in workplace dyads. Results from a field study in daycare centers showed that legitimate power (a dimension of positional power) was positively associated with incivility. In contrast, personal power-referent power and expert power-was positively associated altruism and was negatively associated with incivility. Referent power was a stronger predictor of both altruism and incivility for individuals with low humility than those with high humility. Coercive power was a stronger predictor of incivility for individuals with high humility than those with low humility.

76 FR 77963 - Oglethorpe Power Corporation; Proposed Biomass Power Plant

Science.gov (United States)

2011-12-15

... Service Oglethorpe Power Corporation; Proposed Biomass Power Plant AGENCY: Rural Utilities Service, USDA... related to possible financial assistance to Oglethorpe Power Corporation's (Oglethorpe) for the... online at the following Web site: http://www.rurdev.usda.gov/UWP-OglethorpePower.html and at the: Warren...

Impact of Wind Power Generation on European Cross-Border Power Flows

DEFF Research Database (Denmark)

Zugno, Marco; Pinson, Pierre; Madsen, Henrik

2013-01-01

analysis is employed in order to reduce the problem dimension. Then, nonlinear relationships between forecast wind power production as well as spot price in Germany, by far the largest wind power producer in Europe, and power flows are modeled using local polynomial regression. We find that both forecast...... wind power production and spot price in Germany have substantial nonlinear effects on power transmission on a European scale.......A statistical analysis is performed in order to investigate the relationship between wind power production and cross-border power transmission in Europe. A dataset including physical hourly cross-border power exchanges between European countries as dependent variables is used. Principal component...

Instantaneous power theory and applications to power conditioning

CERN Document Server

Akagi, Hirofumi; Aredes, Mauricio

2017-01-01

This new edition, written by a team of experts in the field, is fully updated with information on the latest electric power technology. The instantaneous power theory, or “the p-q theory,” makes clear the physical meaning of what instantaneous real and imaginary power is in a three-phase circuit. Moreover, it provides insight into how energy flows from a source to a load, or circulates between phases, in a three-phase circuit. This theory can be used in the design and understanding of FACTS (Flexible AC Transmission System) compensators. The book introduces many concepts in the field of active filtering that are unique to this edition. It provides a study tool for final year undergraduate students, graduate students and engineers dealing ith harmonic pollution problems, reactive power compensation or power quality in general.

Power from waste. [Power plant at landfill site

Energy Technology Data Exchange (ETDEWEB)

Anon,

1991-01-01

Base Load Systems Ltd, a company in the United Kingdom, has just commissioned a power plant in Leicestershire which uses waste gases from a landfill site. The gases power two specially modified turbo charged engine and generator packages. The plant will use approximately 100 cu meters of landfill gas per hour and is expected to feed 1.5MW of electrical power into the supply network of East Midlands Electricity. Once the landfill site has been completely filled and capped with clay, it is estimated that the electrical power output will be 4 MW. At present, since their are no customers for heat in the vicinity, 100 KW of the electricity produced are used to run fans to dissipate the 2.5 MW of waste heat. Base load is also involved elsewhere in combined heat and power projects. (UK).

Power generation statistics

International Nuclear Information System (INIS)

Kangas, H.

2001-01-01

The frost in February increased the power demand in Finland significantly. The total power consumption in Finland during January-February 2001 was about 4% higher than a year before. In January 2001 the average temperature in Finland was only about - 4 deg C, which is nearly 2 degrees higher than in 2000 and about 6 degrees higher than long term average. Power demand in January was slightly less than 7.9 TWh, being about 0.5% less than in 2000. The power consumption in Finland during the past 12 months exceeded 79.3 TWh, which is less than 2% higher than during the previous 12 months. In February 2001 the average temperature was - 10 deg C, which was about 5 degrees lower than in February 2000. Because of this the power consumption in February 2001 increased by 5%. Power consumption in February was 7.5 TWh. The maximum hourly output of power plants in Finland was 13310 MW. Power consumption of Finnish households in February 2001 was about 10% higher than in February 2000, and in industry the increase was nearly zero. The utilization rate in forest industry in February 2001 decreased from the value of February 2000 by 5%, being only about 89%. The power consumption of the past 12 months (Feb. 2000 - Feb. 2001) was 79.6 TWh. Generation of hydroelectric power in Finland during January - February 2001 was 10% higher than a year before. The generation of hydroelectric power in Jan. - Feb. 2001 was nearly 2.7 TWh, corresponding to 17% of the power demand in Finland. The output of hydroelectric power in Finland during the past 12 months was 14.7 TWh. The increase from the previous 12 months was 17% corresponding to over 18% of the power demand in Finland. Wind power generation in Jan. - Feb. 2001 was exceeded slightly 10 GWh, while in 2000 the corresponding output was 20 GWh. The degree of utilization of Finnish nuclear power plants in Jan. - Feb. 2001 was high. The output of these plants was 3.8 TWh, being about 1% less than in Jan. - Feb. 2000. The main cause for the

Dynamic Reactive Power Compensation of Large Scale Wind Integrated Power System

DEFF Research Database (Denmark)

Rather, Zakir Hussain; Chen, Zhe; Thøgersen, Paul

2015-01-01

wind turbines especially wind farms with additional grid support functionalities like dynamic support (e,g dynamic reactive power support etc.) and ii) refurbishment of existing conventional central power plants to synchronous condensers could be one of the efficient, reliable and cost effective option......Due to progressive displacement of conventional power plants by wind turbines, dynamic security of large scale wind integrated power systems gets significantly compromised. In this paper we first highlight the importance of dynamic reactive power support/voltage security in large scale wind...... integrated power systems with least presence of conventional power plants. Then we propose a mixed integer dynamic optimization based method for optimal dynamic reactive power allocation in large scale wind integrated power systems. One of the important aspects of the proposed methodology is that unlike...

Vehicle-to-Grid Power in Danish Electric Power Systems

DEFF Research Database (Denmark)

Pillai, Jayakrishnan Radhakrishna; Bak-Jensen, Birgitte

2009-01-01

The integration of renewable energy systems is often constrained by the variable nature of their output. This demands for the services of storing the electricity generated from most of the renewable energy sources. Vehicle-to-grid (V2G) power could use the inherent energy storage of electric...... vehicles and its quick response time to balance and stabilize a power system with fluctuating power. This paper outlines the use of battery electric vehicles in supporting large-scale integration of renewable energy in the Danish electric power systems. The reserve power requirements for a high renewable...... energy penetration could be met by an amount of V2G based electric vehicles less than 10% of the total vehicle need in Denmark. The participation of electric vehicle in ancillary services would earn significant revenues to the vehicle owner. The power balancing services of electric vehicles...

Rethinking Family Power.

Science.gov (United States)

Kranichfeld, Marion L.

1987-01-01

Men's power is emphasized in the family power literature on marital decision making. Little attention has been paid to women's power, accrued through their deeper embeddedness in intrafamilial roles. Micro-level analysis of family power demonstrates that women's positions in the family power structure rest not on the horizontal marital tie but…

Thermoelectric self-cooling for power electronics: Increasing the cooling power

International Nuclear Information System (INIS)

Martinez, Alvaro; Astrain, David; Aranguren, Patricia

2016-01-01

Thermoelectric self-cooling was firstly conceived to increase, without electricity consumption, the cooling power of passive cooling systems. This paper studies the combination of heat pipe exchangers and thermoelectric self-cooling, and demonstrates its applicability to the cooling of power electronics. Experimental tests indicate that source-to-ambient thermal resistance reduces by around 30% when thermoelectric self-cooling system is installed, compared to that of the heat pipe exchanger under natural convection. Neither additional electric power nor cooling fluids are required. This thermal resistance reaches 0.346 K/W for a heat flux of 24.1 kW/m"2, being one order of magnitude lower than that obtained in previous designs. In addition, the system adapts to the cooling demand, reducing this thermal resistance for increasing heat. Simulation tests have indicated that simple system modifications allow relevant improvements in the cooling power. Replacement of a thermoelectric module with a thermal bridge leads to 33.54 kW/m"2 of top cooling power. Likewise, thermoelectric modules with shorter legs and higher number of pairs lead to a top cooling power of 44.17 kW/m"2. These results demonstrate the applicability of thermoelectric self-cooling to power electronics. - Highlights: • Cooling power of passive systems increased. • No electric power consumption. • Applicable for the cooling of power electronics. • Up to 44.17 kW/m"2 of cooling power, one order of magnitude higher. • Source-to-ambient thermal resistance reduces by 30%.

Operating experience feedback on lose of offsite power supply for nuclear power plant

International Nuclear Information System (INIS)

Jiao Feng; Hou Qinmai; Che Shuwei

2013-01-01

The function of the service power system of a nuclear power plant is to provide safe and reliable power supply for the nuclear power plant facilities. The safety of nuclear power plant power supply is essential for nuclear safety. The serious accident of Fukushima Daiichi nuclear power plant occurred due to loss of service power and the ultimate heat sink. The service power system has two independent offsite power supplies as working power and auxiliary power. This article collected events of loss of offsite power supply in operating nuclear power plants at home and abroad, and analyzed the plant status and cause of loss of offsite power supply events, and proposed improvement measures for dealing with loss of offsite power supply. (authors)

Irregular meal pattern-effects on energy expenditure, metabolism and appetite regulation: a randomized controlled trial in healthy normal-weight women

OpenAIRE

Alhussain, Maha H; Macdonald, Ian A.; Taylor, Moira A.

2016-01-01

Background: Obesity is increasing in parallel with greater all-day food availability. The latter may promote meal irregularity, dysregulation of the energy balance, and poor metabolic health.\\ud Objective: We investigated the effect of meal irregularity on the thermic effect of food (TEF), lipid concentrations, carbohydrate metabolism, subjective appetite, and gut hormones in healthy women.\\ud Design: Eleven normal-weight women (18–40 y of age) were recruited in a randomized crossover trial w...

Proceedings of the International Symposium on Frozen Soil Impacts on Agricultural, Range, and Forest Lands Held at Spokane, Washington on March 21-22, 1990

Science.gov (United States)

1990-03-01

the United States. The soils were: a Cecil sandy loam (clayey, kaolinitic, thermic Typic Hapludult) from Watkinsville, GA ; a Barnes loam (fine loamy...1987). GLEAMS user manual. Lab Note South East Watershed Research Laboratory 110 187 WGK, Tifton , Ge, 1987. Lane, L.J., and V. A. Ferreira, (1980...as caps for processed uranium mill tailings in the western United States. The purpose of these barriers is to control radon gas release. The soil

Volumetric and superficial characterization of carbon activated

International Nuclear Information System (INIS)

Carrera G, L.M.; Garcia S, I.; Jimenez B, J.; Solache R, M.; Lopez M, B.; Bulbulian G, S.; Olguin G, M.T.

2000-01-01

The activated carbon is the resultant material of the calcination process of natural carbonated materials as coconut shells or olive little bones. It is an excellent adsorbent of diluted substances, so much in colloidal form, as in particles form. Those substances are attracted and retained by the carbon surface. In this work is make the volumetric and superficial characterization of activated carbon treated thermically (300 Centigrade) in function of the grain size average. (Author)

Volumetric and superficial characterization of carbon activated; Caracterizacion volumetrica y superficial de carbon activado

Energy Technology Data Exchange (ETDEWEB)

Carrera G, L.M.; Garcia S, I.; Jimenez B, J.; Solache R, M.; Lopez M, B.; Bulbulian G, S.; Olguin G, M.T. [Departamento de Quimica, Gerencia de Ciencias Basicas, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

2000-07-01

The activated carbon is the resultant material of the calcination process of natural carbonated materials as coconut shells or olive little bones. It is an excellent adsorbent of diluted substances, so much in colloidal form, as in particles form. Those substances are attracted and retained by the carbon surface. In this work is make the volumetric and superficial characterization of activated carbon treated thermically (300 Centigrade) in function of the grain size average. (Author)

Power System Operation with Large-Scale Wind Power in Liberalised Environments

International Nuclear Information System (INIS)

Ummels, B.C.

2009-01-01

The disadvantages of producing electricity from fossil fuels are that their supply is finite and unevenly distributed across the earth. Conventional power stations also emit greenhouse gases. Therefore, sustainable alternatives must be developed, such as wind power. The disadvantages of wind are that it may or may not blow and that it is unpredictable. Th generation of electricity must however always equal the consumption. This makes the integration of wind power in the electricity system more difficult. This thesis investigates the integration of wind power into the existing power system. Simulation models are developed and used to explore the operation of power systems with a lot of wind power. The simulations provide a picture of the reliability, cost and emission of CO2 of the generation of electricity, with and without wind power. The research also takes into account electricity exchange on international markets. Possible solutions for integrating wind power, such as flexible power plants and energy storage, are investigated as well

Nuclear power plants

International Nuclear Information System (INIS)

1985-01-01

Data concerning the existing nuclear power plants in the world are presented. The data was retrieved from the SIEN (Nuclear and Energetic Information System) data bank. The information are organized in table forms as follows: nuclear plants, its status and type; installed nuclear power plants by country; nuclear power plants under construction by country; planned nuclear power plants by country; cancelled nuclear power plants by country; shut-down nuclear power plants by country. (E.G.) [pt

SNS AC Power Distribution and Reliability of AC Power Supply

CERN Document Server

Holik, Paul S

2005-01-01

The SNS Project has 45MW of installed power. A design description under the Construction Design and Maintenance (CDM) with regard to regulations (OSHA, NFPA, NEC), reliability issues and maintenance of the AC power distribution system are herewith presented. The SNS Project has 45MW of installed power. The Accelerator Systems are Front End (FE)and LINAC KLYSTRON Building (LK), Central Helium Liquefier (CHL), High Energy Beam Transport (HEBT), Accumulator Ring and Ring to Target Beam Transport (RTBT) Support Buildings have 30MW installed power. FELK has 16MW installed, majority of which is klystron and magnet power supply system. CHL, supporting the super conducting portion of the accelerator has 7MW installed power and the RING Systems (HEBT, RING and RTBT) have also 7MW installed power.*

Mathematical Modelling of the Thermical Regime in the Continous Casting Process

Directory of Open Access Journals (Sweden)

Monika Erika POPA

2005-10-01

Full Text Available Continuous casting is one of the prominent methods of production of casts. Effective design and operation of continuous casting machines needs complete analysis of the continuous casting process. In this paper the basic principles of continuous casting and its heat transfer analysis using the finite element method are presented. In the analysis phase change is assumed to take place at constant temperature. A front tracking algorithm has been developed to predict the position of the solidification front at each step. Finally, examples that are solved by the proposed algorithm are discussed. The results show that there is a good agreement between the method developed in this work and other previously reported works.

Thermometric carottage measurement and thermic flow in Cheb basin (West Czech)

International Nuclear Information System (INIS)

Irovska, J.; Kobr, M.; Cermak, V.

2002-01-01

The basic method applied for carottage measurement in Cheb basin was the measurement of natural gamma activity and resistance measurement. In selected drillings for search of coal deposits the neutron-neutron profiling, density gamma-gamma carottage and inclinometry were applied. This standard method was refill with measurements of hydrogeology conditions in a drill (resistivimetry, thermometry, photometry, flowmeter). In the Cheb basin 36 drills have stable thermometric measurements of 850 drills with the depth more than 45 m. From these measurements the map of thermal flow density was plotted. On the map 4 anomalies are manifested

An on-line mass-separator for thermically ionisable fission products: OSTIS

International Nuclear Information System (INIS)

Wuensch, K.-D.

1978-01-01

A mass separator has been designed and built for the installed at an external neutron guide tube (flux approximately 10 9 nsub(th)/s cm 2 ) of the High Flux Reactor of the Institute Laue-Langevin in Grenoble. The ion source consists of a high temperature oven containing fissile target material (approximately 2 g 235 U) embedded in porous carbon. Fission products formed in the target are thermalised in the carbon where only the alkali fission products diffuse quickly to the extraction hole. There only Rb and Cs are thermally ionized. Accelerated to 20 kV, these ions pass through a deflecting magnetic field (rhosub(m) approximately 215 mm, rho=77.5 0 ) for mass analysis and an electrostatic quadrupole to form a 5 mm diameter spot about 1 m outside the concrete shielding. Intensities of some 10 6 atoms per second were reached. The system allows all types of nuclear spectroscopy of Rb, Cs and their β-decay chain daughters as well as the measurement of yields and fission neutrons. It has been in nearly continuous operation for more than two years in Grenoble and first results are reported. (Auth.)

Wireless power pad with local power activation for portable devices

NARCIS (Netherlands)

Waffenschmidt, E.; Zheglov, V.

2007-01-01

Wireless power transfer by magnetic induction offers a simple to use way to recharge mobile devices like e.g. mobile phone, music players or medical sensors. As shown by a previous report and an existing Power Pad demonstrator, wireless inductive power transfer is possible with a good power

Power quality improvement of unbalanced power system with distributed generation units

DEFF Research Database (Denmark)

Hu, Y.; Chen, Zhe; Excell, P.

2011-01-01

This paper presents a power electronic system for improving the power quality of the unbalanced distributed generation units in three-phase four-wire system. In the system, small renewable power generation units, such as small PV generator, small wind turbines may be configured as single phase...... and control of the converter are described. Simulation results have demonstrated that the system can effectively correct the unbalance and enhance the system power quality....... generation units. The random nature of renewable power sources may result in significant unbalance in the power network and affect the power quality. An electronic converter system is proposed to correct the system unbalance and harmonics so as to deal with the power quality problems. The operation...

Impact of Offshore Wind Power Integrated by VSC-HVDC on Power Angle Stability of Power Systems

Science.gov (United States)

Lu, Haiyang; Tang, Xisheng

2017-05-01

Offshore wind farm connected to grid by VSC-HVDC loses frequency support for power system, so adding frequency control in wind farm and VSC-HVDC system is an effective measure, but it will change wind farm VSC-HVDC’s transient stability on power system. Through theoretical analysis, concluding the relationship between equivalent mechanical power and electromagnetic power of two-machine system with the active power of wind farm VSC-HVDC, then analyzing the impact of wind farm VSC-HVDC with or without frequency control and different frequency control parameters on angle stability of synchronous machine by EEAC. The validity of theoretical analysis has been demonstrated through simulation in PSCAD/EMTDC.

Power quality assessment

International Nuclear Information System (INIS)

Fathi, H.M.E.

2012-01-01

The electrical power systems are exposed to different types of power quality disturbances problems. Assessment of power quality is necessary for maintaining accurate operation of sensitive equipment's especially for nuclear installations, it also ensures that unnecessary energy losses in a power system are kept at a minimum which lead to more profits. With advanced in technology growing of industrial / commercial facilities in many region. Power quality problems have been a major concern among engineers; particularly in an industrial environment, where there are many large-scale type of equipment. Thus, it would be useful to investigate and mitigate the power quality problems. Assessment of Power quality requires the identification of any anomalous behavior on a power system, which adversely affects the normal operation of electrical or electronic equipment. The choice of monitoring equipment in a survey is also important to ascertain a solution to these power quality problems. A power quality assessment involves gathering data resources; analyzing the data (with reference to power quality standards); then, if problems exist, recommendation of mitigation techniques must be considered. The main objective of the present work is to investigate and mitigate of power quality problems in nuclear installations. Normally electrical power is supplied to the installations via two sources to keep good reliability. Each source is designed to carry the full load. The Assessment of power quality was performed at the nuclear installations for both sources at different operation conditions. The thesis begins with a discussion of power quality definitions and the results of previous studies in power quality monitoring. The assessment determines that one source of electricity was deemed to have relatively good power quality; there were several disturbances, which exceeded the thresholds. Among of them are fifth harmonic, voltage swell, overvoltage and flicker. While the second

Dynamic Reactive Power Control in Offshore HVDC Connected Wind Power Plants

DEFF Research Database (Denmark)

Sakamuri, Jayachandra N.; Cutululis, Nicolaos Antonio; Rather, Zakir Hussain

2016-01-01

This paper presents a coordinated reactive power control for a HVDC connected cluster of offshore wind power plants (WPPs). The reactive power reference for the WPP cluster is estimated by an optimization algorithm aiming at minimum active power losses in the offshore AC Grid. For each optimal......, such as wind turbine (WT) terminal, collector cable, and export cable, on the dynamic voltage profile of the offshore grid is investigated. Furthermore, the dynamic reactive power contribution from WTs from different WPPs of the cluster for such faults has also been studied....... reactive power set point, the OWPP cluster controller generates reactive power references for each WPP which further sends the AC voltage/ reactive power references to the associated WTs based on their available reactive power margin. The impact of faults at different locations in the offshore grid...

Nuclear power

International Nuclear Information System (INIS)

King, P.

1990-01-01

Written from the basis of neutrality, neither for nor against nuclear power this book considers whether there are special features of nuclear power which mean that its development should be either promoted or restrained by the State. The author makes it dear that there are no easy answers to the questions raised by the intervention of nuclear power but calls for openness in the nuclear decision making process. First, the need for energy is considered; most people agree that energy is the power to progress. Then the historicalzed background to the current position of nuclear power is given. Further chapters consider the fuel cycle, environmental impacts including carbon dioxide emission and the greenhouse effect, the costs, safety and risks and waste disposal. No conclusion either for or against nuclear power is made. The various shades of opinion are outlined and the arguments presented so that readers can come to their own conclusions. (UK)

Reactor power control systems in nuclear power plants

International Nuclear Information System (INIS)

Nakajima, Kazuo.

1980-01-01

Purpose: To enable power control by automatic control rod operation based on the calculated amounts of operation for the control rods determined depending on a power set value from reactor operators or on power variation amounts from other devices. Constitution: When an operator designates an automatic selection by way of a control rod operation panel, automatic signals are applied to a manual-automatic switching circuit and the mode judging circuit of a rod pattern control device. Then, mode signals such as for single operation, load setting, load following and the like produced by the operator are judged in a circuit, wherein a control rod pattern operation circuit calculates the designation for the control rods and the operation amounts for the control rods depending on the designated modes and automatic control is conducted for the control rods by a rod position control circuit, a rod drive control device and the like connected at a rod position monitor device. The reactor power is thus controlled automatically to reduce the operator's labours. The automatic power control can also be conducted in the same manner by the amount of power variations applied to the device from the external device. (Yoshino, Y.)

Reactor power control device in BWR power plant

International Nuclear Information System (INIS)

Kurosawa, Tsuneo.

1997-01-01

The present invention provides a device for controlling reactor power based on a start-up/shut down program in a BWR type reactor, as well as for detecting deviation, if occurs, of the power from the start-up/shut down program, to control a recycling flow rate control system or control rod drive mechanisms. Namely, a power instruction section successively executes the start-up/shut down program and controls the coolant recycling system and the control rod driving mechanisms to control the power. A current state monitoring and calculation section receives a process amount, calculates parameters showing the plant state, compares/monitors them with predetermined values, detecting the deviation, if occurs, of the plant state from the start-up/shut down program, and prevents output of a power increase control signal which leads to power increase. A forecasting and monitoring/calculation section forecasts and calculates the plant state when not yet executed steps of the start-up/shut down program are performed, stops the execution of the start-up/shut down program in the next step in a case of forecasting that the results of the calculation will deviate from the start-up/shut down program. (I.S.)

Wind power and market power in competitive markets

International Nuclear Information System (INIS)

Twomey, Paul; Neuhoff, Karsten

2010-01-01

Average market prices for intermittent generation technologies are lower than for conventional generation. This has a technical reason but can be exaggerated in the presence of market power. When there is much wind smaller amounts of conventional generation technologies are required, and prices are lower, while at times of little wind prices are higher. This effect reflects the value of different generation technologies to the system. But under conditions of market power, conventional generators with market power can further depress the prices if they have to buy back energy at times of large wind output and can increase prices if they have to sell additional power at times of little wind output. This greatly exaggerates the effect. Forward contracting does not reduce the effect. An important consequence is that allowing market power profit margins as a support mechanism for generation capacity investment is not a technologically neutral policy.

TinyPower – Power conversion on a tiny scale

DEFF Research Database (Denmark)

Han, Anpan; Jørgensen, Anders Michael

2014-01-01

The world surrounding us is filled with devices relying on electrical power and the rise of internet-of-thingswill mean that powering devices will remain important in the future. The size and cost of the power supplyhas become a dominant factor in many applications. At the same time, most of the ...... project is an ambitious approach to taking miniature power converters into a new domainand the trickle-down effect on micro fabricated inductors can hopefully benefit other projects....

A battery-powered high-current power supply for superconductors

CERN Document Server

Wake, M; Suda, K

2002-01-01

Since superconductors do not require voltages, a high-current power supply could run with low power if the voltage is sufficiently reduced. Even a battery-powered power supply could give as much as 2,000A for a superconductor. To demonstrate this hypothesis, a battery-powered 2,000A power supply was constructed. It uses an IGBT chopper and Schottky diode together with a specially arranged transformer to produce a high current with low voltage. Testing of 2,000A operation was performed for about 1.5 hr using 10 car batteries. Charging time for this operation was 8 hr. Ramping control was smooth and caused no trouble. Although the IGBT frequency ripple of 16.6 kHz was easily removed using a passive filter, spike noise remained in the output voltage. This ripple did not cause any trouble in operating a pancake-type inductive superconducting load. (author)

Two wind power prognosis criteria and regulating power costs

DEFF Research Database (Denmark)

Nielsen, Claus S.; Ravn, Hans F.; Schaumburg-Müller, Camilla

2003-01-01

. Basically, the choice is between focusing on predicting the energy content of the wind and focusing on the cost of buying regulating power to compensate for the prognosis errors. It will be shown that it can be expected that the two power curves thus estimated will differ, and that therefore also the hourly......The objective of the present work is to investigate the consequences of the choice of criterion in short-term wind power prognosis. This is done by investigating the consequences of choice of objective function in relation to the estimation of the power curve that is applied in the prognoses...... wind power production predicted will differ. In turn this will influence the operation and economics of the system. The consequences of this are illustrated by application to the integration of wind power in the Danish parts of the Nordpool area, using recent data. Using a regression analysis...

Effects of a power shortage in the Tokyo metropolitan area on awareness of nuclear power generation and power savings behavior

International Nuclear Information System (INIS)

Kitada, Atsuko

2004-01-01

The shutdown of a number of nuclear power stations of the Tokyo Electric Power Company in the summer of 2003 caused a power shortage problem in the Tokyo Metropolitan area. To examine the effects of the power shortage, in September 2003 a survey was conducted in the service areas of the Kansai Electric Power Company (Kansai region) and the Tokyo Electric Power Company (Kanto region). This survey was part of a wider opinion survey begun in 1993 concerning nuclear power generation. The results of the September 2003 survey are as follows: The degree of recognition of the power shortage problem in the Metropolitan area was high, with 40% of respondents in the Kansai region and nearly 70% in the Kanto region understanding that the shortage was caused by the shutdown of several nuclear power station. The overall awareness of nuclear power generation was little affected in both the Kansai and Kanto regions, though the sense of a shortage of the generating capacity had been raised slightly. Once respondents knew about the power shortage problem, they estimated the likelihood of an occurrence of large-scale service interruption to be low, nearly at an even chance, and they had been only slightly worried about it, essentially viewing the problem optimistically. In the Kanto region, where public relations activities for power savings had been actively pursued, the frequency of experiencing exposure to such public relations activities was remarkably higher than in the Kansai region. The relation between exposure to public relations activities for power savings and power savings behavior was analyzed using quantification method II. Analysis results suggest that public relations activities for power savings in the Kanto region had the effect of urging power savings behavior. However, the difference in the rate of putting power savings behavior into practice was small between the Kanto and Kansai regions, indicating that public relation activities for power savings in the Kanto

Power system damping - Structural aspects of controlling active power

Energy Technology Data Exchange (ETDEWEB)

Samuelsson, O.

1997-04-01

Environmental and economical aspects make it difficult to build new power lines and to reinforce existing ones. The continued growth in demand for electric power must therefore to a great extent be met by increased loading of available lines. A consequence is that power system damping is reduced, leading to a risk of poorly damped power oscillations between the generators. This thesis proposes the use of controlled active loads to increase damping of such electro-mechanical oscillations. The focus is on structural aspects of controller interaction and of sensor and actuator placement. On-off control based on machine frequency in a single machine infinite bus system is analysed using energy function analysis and phase plane plots. An on-off controller with estimated machine frequency as input has been implemented. At a field test it damped oscillations of a 0.9 MW hydro power generator by controlling a 20kW load. The linear analysis uses two power system models with three and twenty-three machines respectively. Each damper has active power as output and local bus frequency or machine frequency as input. The power system simulator EUROSTAG is used both for generation of the linearized models and for time simulations. Measures of active power mode controllability and phase angle mode observability are obtained from the eigenvectors of the differential-algebraic models. The geographical variation in the network of these quantities is illustrated using the resemblance to bending modes of flexible mechanical structures. Eigenvalue sensitivities are used to determine suitable damper locations. A spring-mass equivalent to an inter-area mode provides analytical expressions, that together with the concept of impedance matching explain the structural behaviour of the power systems. For large gains this is investigated using root locus plots. 64 refs, 99 figs, 20 tabs

Financing the electric power utilities, especially the nuclear power in Japan

International Nuclear Information System (INIS)

Tajima, T.

1975-04-01

Electric power demands in Japan have shown a remarkable growth at an annual rate of 12% since 1965. Nine electric power companies have invested large amounts of money so far, amounting to over 1 trillion yen every year since 1972. A survey of the electric power supply system and an estimation of the electric power demands in 1980 and in 1985 are given. It is expected that the main portion of electric power in the future will gradually be generated by nuclear plants. Financial features of the electrical power utilities, the credit risk of the electric power utilities, and the raising of funds by electric power utilities are discussed. It is concluded that it will be necessary (1) to expand the capital market, (2) to enable the electric power companies to issue a sufficient amount of bonds, (3) to make the Government financing institutions, such as the Japan Development Bank, provide the electric power companies with larger funds on a long-term and low-interest rate basis, and (4) even to take such drastic steps as subsidizing interest on private loans to the electric power companies. (B.P.)

China's power policy

International Nuclear Information System (INIS)

Mayer, M.

2006-01-01

Whether the People's Republic of China may develop to an economical super-government in future depends on the amount of power and resources of this land. The security of power supply is in an extremely prominent position in the Agenda of the Chinese government. Under this aspect the author of the contribution under consideration reports on the power policy of China. The main aspects of this contribution are: (a) Trends of power consumption, productions and imports of power; (b) Power political targets, measures and instruments of China; (c) Characteristics, national and international impacts of the power policy of China. Due to the economical activities of the chinese oil industry worldwide as well as due to the increasing dependence from imports of petroleum and natural oil, China becomes a global player. Thus, one may expect an intensification of Beijing's economical activities with an increased military component. Nevertheless, the power policy of China is an important factor in the global competition according to fossil resources. In order to understand the future behaviour of China's power policy, one may have to take notice of the strategies relating the power policy and relating to foreign affairs. Furthermore, trends and problematic areas concerning the securitization of the power supply in the national area have to be observed

On grid-connected power electronic systems: power quality improvement application

International Nuclear Information System (INIS)

Etxeberria-Otadui, I.

2003-09-01

The present PhD thesis deals with distribution grid-connected power electronic devices. The main focus has been power quality improvement with power electronic devices. The theoretical aspects and the power quality improvement techniques are presented and discussed. Power electronic devices are then presented, modelled and controlled. Original disturbance identification, power management and current/voltage control methods have been proposed, tested and analysed. A flexible test-bench, composed of a series and a shunt compensator, has been designed and built in order to test the studied control algorithms. These tests have permitted to experimentally evaluate and validate the proposed control algorithms and to make evident several problems that are not always visible on the theory. The conclusions outline the main short and mid term objectives and challenges in the field of power quality improvement devices. (author)

Power quality enhancement of renewable energy source power network using SMES system

International Nuclear Information System (INIS)

Seo, H.R.; Kim, A.R.; Park, M.; Yu, I.K.

2011-01-01

Power quality enhancement of a renewable energy source power network is performed by a real-toroidal-type SMES coil. SMES unit charges and discharges the HTS coil to mitigate the fluctuation of PV system output power. The grid connected PV and SMES system has been modeled and simulated using power-hard-in-the-loop simulation. The PHILS results demonstrated the effectiveness of the SMES system for enhancing power quality. This paper deals with power quality enhancement of renewable energy source power network using SMES system and describes the operation characteristics of HTS SMES system using real-toroidal-type SMES coil for smoothening the fluctuation of large-scale renewable energy source such as photovoltaic (PV) power generation system. It generates maximum power of PV array under various weather conditions. SMES unit charges and discharges the HTS coil to mitigate the fluctuation of PV system output power. The SMES unit is controlled according to the PV array output and the utility power quality conditions. The grid connected PV and SMES system has been modeled and simulated using power-hard-in-the-loop simulation (PHILS). The PHILS results demonstrated the effectiveness of the SMES system for enhancing power quality in power network including large-scale renewable energy source, especially PV power generation system.

Generalized Power Domination

OpenAIRE

Omerzel, Aleš

2014-01-01

The power domination problem is an optimization problem that has emerged together with the development of the power networks. It is important to control the voltage and current in all the nodes and links in a power network. Measuring devices are expensive, which is why there is a tendency to place a minimum number of devices in a power network so that the network remains fully supervised. The k-power domination is a generalization of the power domination. The thesis represents the rules of th...

Power Quality Issues on Wind Power Installations in Denmark

DEFF Research Database (Denmark)

Sørensen, Poul Ejnar; Cutululis, Nicolaos Antonio; Lund, Torsten

2007-01-01

offshore wind farms connected at transmission level. In this perspective, the power quality issues are divided into local issues particularly related to the voltage quality in the distribution systems and global issues related to the power system control and stability. Power quality characteristics of wind...

The electric power engineering handbook electric power generation, transmission, and distribution

CERN Document Server

Grigsby, Leonard L

2012-01-01

Featuring contributions from worldwide leaders in the field, the carefully crafted Electric Power Generation, Transmission, and Distribution, Third Edition (part of the five-volume set, The Electric Power Engineering Handbook) provides convenient access to detailed information on a diverse array of power engineering topics. Updates to nearly every chapter keep this book at the forefront of developments in modern power systems, reflecting international standards, practices, and technologies. Topics covered include: * Electric Power Generation: Nonconventional Methods * Electric Power Generation

Damping of Low Frequency Power System Oscillations with Wind Power Plants

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz

of wind power plants on power system low frequency oscillations and identify methods and limitations for potential contribution to the damping of such oscillations. Consequently, the first part of the studies focuses on how the increased penetration of wind power into power systems affects their natural...... oscillatory performance. To do so, at first a generic test grid displaying a complex inter-area oscillation pattern is introduced. After the evaluation of the test grid oscillatory profile for various wind power penetration scenarios, it is concluded that full-converter based wind power plant dynamics do......-synchronous power source. The main body of the work is devoted to the damping control design for wind power plants with focus on the impact of such control on the plant operation. It can be expected that the referred impact is directly proportional to the control effort, which for power processing devices should...

Green Power Partnership 100 Green Power Users

Science.gov (United States)

EPA's Green Power Partnership is a voluntary program designed to reduce the environmental impact of electricity generation by promoting renewable energy. Partners on this list use green power to meet 100 of their U.S. organization-wide electricity use.

A high-power versatile wireless power transfer for biomedical implants.

Science.gov (United States)

Jiang, Hao; Zhang, Jun Min; Liou, Shy Shenq; Fechter, Richard; Hirose, Shinjiro; Harrison, Michael; Roy, Shuvo

2010-01-01

Implantable biomedical actuators are highly desired in modern medicine. However, how to power up these biomedical implants remains a challenge since most of them need more than several hundreds mW of power. The air-core based radio-frequency transformer (two face-to-face inductive coils) has been the only non-toxic and non-invasive power source for implants for the last three decades [1]. For various technical constraints, the maximum delivered power is limited by this approach. The highest delivered power reported is 275 mW over 1 cm distance [2]. Also, the delivered power is highly vulnerable to the coils' geometrical arrangement and the electrical property of the medium around them. In this paper, a novel rotating-magnets based wireless power transfer that can deliver ∼10 W over 1 cm is demonstrated. The delivered power is significantly higher than the existing start-of-art. Further, the new method is versatile since there is no need to have the impedance matching networks that are highly susceptible to the operating frequency, the coil arrangement and the environment.

Space power plants and power-consuming industrial systems

International Nuclear Information System (INIS)

Latyshev, L.; Semashko, N.

1996-01-01

An opportunity to create the space power production on the basis of solar, nuclear and fusion energies is analyzed. The priority of solar power production as the most accessible and feasible in comparison with others is emphasized. However, later on, it probably will play an auxiliary role. The possibilities of fusion power production, as a basic one in future, are also considered. It is necessary to create reactors using the fueling cycle with helium-3 (instead of tritium and deuterium, later on). The reaction products--charged particles, mainly--allow one to organize the system of direct fusion energy conversion into electricity. The produced energy is expected not to be transmitted to Earth, but an industry in space is expected to be produced on its basis. The industrial (power and science-consuming) objects located on a whole number of space apparatus will form a single complex with its own basic power plant. The power transmission within the complex will be realized with high power density fluxes of microwave radiation to short distances with their receivers at the objects. The necessary correction of the apparatus positions in the complex will be done with ion and plasma thrusters. The materials present on the Moon, asteroids and on other planets can serve as raw materials for industrial objects. Such an approach will help to improve the ecological state on Earth, to eliminate the necessity in the fast energy consumption growth and to reduce the hazard of global thermal crisis

Methods for Estimation of Market Power in Electric Power Industry

Science.gov (United States)

Turcik, M.; Oleinikova, I.; Junghans, G.; Kolcun, M.

2012-01-01

The article is related to a topical issue of the newly-arisen market power phenomenon in the electric power industry. The authors point out to the importance of effective instruments and methods for credible estimation of the market power on liberalized electricity market as well as the forms and consequences of market power abuse. The fundamental principles and methods of the market power estimation are given along with the most common relevant indicators. Furthermore, in the work a proposal for determination of the relevant market place taking into account the specific features of power system and a theoretical example of estimating the residual supply index (RSI) in the electricity market are given.

Handbook of power systems engineering with power electronics applications

CERN Document Server

Hase, Yoshihide

2012-01-01

Formerly known as Handbook of Power System Engineering, this second edition provides rigorous revisions to the original treatment of systems analysis together with a substantial new four-chapter section on power electronics applications. Encompassing a whole range of equipment, phenomena, and analytical approaches, this handbook offers a complete overview of power systems and their power electronics applications, and presents a thorough examination of the fundamental principles, combining theories and technologies that are usually treated in separate specialised fields, in a single u

High average power solid state laser power conditioning system

International Nuclear Information System (INIS)

Steinkraus, R.F.

1987-01-01

The power conditioning system for the High Average Power Laser program at Lawrence Livermore National Laboratory (LLNL) is described. The system has been operational for two years. It is high voltage, high power, fault protected, and solid state. The power conditioning system drives flashlamps that pump solid state lasers. Flashlamps are driven by silicon control rectifier (SCR) switched, resonant charged, (LC) discharge pulse forming networks (PFNs). The system uses fiber optics for control and diagnostics. Energy and thermal diagnostics are monitored by computers

Industrial power distribution

CERN Document Server

Fehr, Ralph

2016-01-01

In this fully updated version of Industrial Power Distribution, the author addresses key areas of electric power distribution from an end-user perspective for both electrical engineers, as well as students who are training for a career in the electrical power engineering field. Industrial Power Distribution, Second Edition, begins by describing how industrial facilities are supplied from utility sources, which is supported with background information on the components of AC power, voltage drop calculations, and the sizing of conductors and transformers. Important concepts and discussions are featured throughout the book including those for sequence networks, ladder logic, motor application, fault calculations, and transformer connections. The book concludes with an introduction to power quality, how it affects industrial power systems, and an expansion of the concept of power factor, including a distortion term made necessary by the existence of harmonic.

Power control and management of the grid containing largescale wind power systems

Science.gov (United States)

Aula, Fadhil Toufick

The ever increasing demand for electricity has driven many countries toward the installation of new generation facilities. However, concerns such as environmental pollution and global warming issues, clean energy sources, high costs associated with installation of new conventional power plants, and fossil fuels depletion have created many interests in finding alternatives to conventional fossil fuels for generating electricity. Wind energy is one of the most rapidly growing renewable power sources and wind power generations have been increasingly demanded as an alternative to the conventional fossil fuels. However, wind power fluctuates due to variation of wind speed. Therefore, large-scale integration of wind energy conversion systems is a threat to the stability and reliability of utility grids containing these systems. They disturb the balance between power generation and consumption, affect the quality of the electricity, and complicate load sharing and load distribution managing and planning. Overall, wind power systems do not help in providing any services such as operating and regulating reserves to the power grid. In order to resolve these issues, research has been conducted in utilizing weather forecasting data to improve the performance of the wind power system, reduce the influence of the fluctuations, and plan power management of the grid containing large-scale wind power systems which consist of doubly-fed induction generator based energy conversion system. The aims of this research, my dissertation, are to provide new methods for: smoothing the output power of the wind power systems and reducing the influence of their fluctuations, power managing and planning of a grid containing these systems and other conventional power plants, and providing a new structure of implementing of latest microprocessor technology for controlling and managing the operation of the wind power system. In this research, in order to reduce and smooth the fluctuations, two

Adaptive reactive power control of PV power plants for improved power transfer capability under ultra-weak grid conditions

DEFF Research Database (Denmark)

Yang, Dongsheng; Wang, Xiongfei; Liu, Fangcheng

2017-01-01

The Photovoltaic (PV) power plants are usually deployed in remote areas with the high solar irradiance, and their power transfer capabilities can be greatly limited by the large impedance of long-distance transmission lines. This paper investigates first the power transfer limit of the PV power p...

Electric power systems

CERN Document Server

Weedy, B M; Jenkins, N; Ekanayake, J B; Strbac, G

2012-01-01

The definitive textbook for Power Systems students, providing a grounding in essential power system theory while also focusing on practical power engineering applications. Electric Power Systems has been an essential book in power systems engineering for over thirty years. Bringing the content firmly up-to-date whilst still retaining the flavour of Weedy's extremely popular original, this Fifth Edition has been revised by experts Nick Jenkins, Janaka Ekanayake and Goran Strbac. This wide-ranging text still covers all of the fundamental power systems subjects but is now e

Estimation of power system variability due to wind power

NARCIS (Netherlands)

Papaefthymiou, G.; Verboomen, J.; Van der Sluis, L.

2007-01-01

The incorporation of wind power generation to the power system leads to an increase in the variability of the system power flows. The assessment of this variability is necessary for the planning of the necessary system reinforcements. For the assessment of this variability, the uncertainty in the

Power generation using photovoltaic induction in an isolated power network

International Nuclear Information System (INIS)

Kalantar, M.; Jiang, J.

2001-01-01

Owing to increased emphasis on renewable resources, the development of suitable isolated power generators driven by energy sources, the development of suitable isolated power generators driven by energy sources such as photovoltaic, wind, small hydroelectric, biogas and etc. has recently assumed greater significance. A single phase capacitor self excited induction generator has emerged as a suitable candidate of isolated power sources. This paper presents performance analysis of a single phase self-excited induction generator driven by photovoltaic (P V) system for low power isolated stand-alone applications. A single phase induction machine can work as a self-excited induction generator when its rotor is driven at suitable speed by an photovoltaic powered do motor. Its excitation is provided by connecting a single phase capacitor bank at a stator terminals. Either to augment grid power or to get uninterrupted power during grid failure stand-alone low capacity ac generators are used. These are driven by photovoltaic, wind power or I C engines using kerosene, diesel, petrol or biogas as fuel. Self-excitation with capacitors at the stator terminals of the stator terminals of the induction machines is well demonstrated experimentally on a P V powered dc motor-induction machine set. The parameters and the excitation requirements of the induction machine run in self-excited induction generator mode are determined. The effects of variations in prime mover speed,terminal capacitance and load power factor on the machine terminal voltage are studied

Reusing balanced power flow object components for developing harmonic power flow

Energy Technology Data Exchange (ETDEWEB)

Nadarajah, S. [Peninsular Malaysia Electric Utility Co., Kuala Lumpur (Malaysia). Tenaga Nasional Berhad; Nor, K.M.; Abdel-Akher, M. [Malaysia Univ., Kuala Lumpur (Malaysia). Dept. of Electrical Engineering

2005-07-01

Harmonic power flows are used to examine the effects of nonlinear loads on power systems. In this paper, component technology was re-used for the development of a harmonic power flow. The object-oriented power system model (OO-PSM) was developed separately from a solution algorithm. Nodes, lines, and transformers were modelled as entity objects by classes. Power flow solution algorithms were modelled as control objects and encapsulated inside independent software components within the power system component software architecture (PS-COM). Both the OO-PSM and the PS-COM of the balanced power flow were re-used for developing the proposed harmonic power flow. A no-interaction hypothesis was used to consider both fundamental voltages and nonlinear device data dependence. A direct solution voltage node method was also used. The accuracy of the method was demonstrated using IEEE 14 bus and 30 bus test systems. It was concluded that component technology can be used to develop harmonic power flow programs. 7 refs., 2 tabs., 9 figs.

Software-Based Wireless Power Transfer Platform for Various Power Control Experiments

Directory of Open Access Journals (Sweden)

Sun-Han Hwang

2015-07-01

Full Text Available In this paper, we present the design and evaluation of a software-based wireless power transfer platform that enables the development of a prototype involving various open- and closed-loop power control functions. Our platform is based on a loosely coupled planar wireless power transfer circuit that uses a class-E power amplifier. In conjunction with this circuit, we implement flexible control functions using a National Instruments Data Acquisition (NI DAQ board and algorithms in the MATLAB/Simulink. To verify the effectiveness of our platform, we conduct two types of power-control experiments: a no-load or metal detection using open-loop power control, and an output voltage regulation for different receiver positions using closed-loop power control. The use of the MATLAB/Simulink software as a part of the planar wireless power transfer platform for power control experiments is shown to serve as a useful and inexpensive alternative to conventional hardware-based platforms.

Synthesizing modeling of power generation and power limits in energy systems

International Nuclear Information System (INIS)

Sieniutycz, Stanislaw

2015-01-01

Applying the common mathematical procedure of thermodynamic optimization the paper offers a synthesizing or generalizing modeling of power production in various energy generators, such as thermal, solar and electrochemical engines (fuel cells). Static and dynamical power systems are investigated. Dynamical models take into account the gradual downgrading of a resource, caused by power delivery. Analytical modeling includes conversion efficiencies expressed in terms of driving fluxes. Products of efficiencies and driving fluxes determine the power yield and power maxima. While optimization of static systems requires using of differential calculus and Lagrange multipliers, dynamic optimization involves variational calculus and dynamic programming. In reacting mixtures balances of mass and energy serve to derive power yield in terms of an active part of chemical affinity. Power maximization approach is also applied to fuel cells treated as flow engines driven by heat flux and fluxes of chemical reagents. The results of power maxima provide limiting indicators for thermal, solar and SOFC generators. They are more exact than classical reversible limits of energy transformation. - Highlights: • Systematic evaluation of power limits by optimization. • Common thermodynamic methodology for engine systems. • Original, in-depth study of power maxima. • Inclusion of fuel cells to a class of thermodynamic power systems

Power Constrained High-Level Synthesis of Battery Powered Digital Systems

DEFF Research Database (Denmark)

Nielsen, Sune Fallgaard; Madsen, Jan

2003-01-01

We present a high-level synthesis algorithm solving the combined scheduling, allocation and binding problem minimizing area under both latency and maximum power per clock-cycle constraints. Our approach eliminates the large power spikes, resulting in an increased battery lifetime, a property...... of utmost importance for battery powered embedded systems. Our approach extends the partial-clique partitioning algorithm by introducing power awareness through a heuristic algorithm which bounds the design space to those of power feasible schedules. We have applied our algorithm on a set of dataflow graphs...

Reduction technique of drop voltage and power losses to improve power quality using ETAP Power Station simulation model

Science.gov (United States)

Satrio, Reza Indra; Subiyanto

2018-03-01

The effect of electric loads growth emerged direct impact in power systems distribution. Drop voltage and power losses one of the important things in power systems distribution. This paper presents modelling approach used to restructrure electrical network configuration, reduce drop voltage, reduce power losses and add new distribution transformer to enhance reliability of power systems distribution. Restructrure electrical network was aimed to analyse and investigate electric loads of a distribution transformer. Measurement of real voltage and real current were finished two times for each consumer, that were morning period and night period or when peak load. Design and simulation were conduct by using ETAP Power Station Software. Based on result of simulation and real measurement precentage of drop voltage and total power losses were mismatch with SPLN (Standard PLN) 72:1987. After added a new distribution transformer and restructrured electricity network configuration, the result of simulation could reduce drop voltage from 1.3 % - 31.3 % to 8.1 % - 9.6 % and power losses from 646.7 watt to 233.29 watt. Result showed, restructrure electricity network configuration and added new distribution transformer can be applied as an effective method to reduce drop voltage and reduce power losses.

Nuclear power development

International Nuclear Information System (INIS)

Nealey, S.

1990-01-01

The objective of this study is to examine factors and prospects for a resumption in growth of nuclear power in the United States over the next decade. The focus of analysis on the likelihood that current efforts in the United States to develop improved and safer nuclear power reactors will provide a sound technical basis for improved acceptance of nuclear power, and contribute to a social/political climate more conducive to a resumption of nuclear power growth. The acceptability of nuclear power and advanced reactors to five social/political sectors in the U.S. is examined. Three sectors highly relevant to the prospects for a restart of nuclear power plant construction are the financial sector involved in financing nuclear power plant construction, the federal nuclear regulatory sector, and the national political sector. For this analysis, the general public are divided into two groups: those who are knowledgeable about and involved in nuclear power issues, the involved public, and the much larger body of the general public that is relatively uninvolved in the controversy over nuclear power

Power Electronics

Indian Academy of Sciences (India)

They cover a wide spectrum of areas from power supplies to power system ... Ramanarayanan describe the modelling and design of a family of soft transition ... of power when the drive is operating in the braking mode and fast dynamic response. ... time models are extremely important, as they can be included in real time ...

Review of Power System Stability with High Wind Power Penetration

DEFF Research Database (Denmark)

Hu, Rui; Hu, Weihao; Chen, Zhe

2015-01-01

analyzing methods and stability improvement approaches. With increasing wind power penetration, system balancing and the reduced inertia may cause a big threaten for stable operation of power systems. To mitigate or eliminate the wind impacts for high wind penetration systems, although the practical......This paper presents an overview of researches on power system stability with high wind power penetration including analyzing methods and improvement approaches. Power system stability issues can be classified diversely according to different considerations. Each classified issue has special...... and reliable choices currently are the strong outside connections or sufficient reserve capacity constructions, many novel theories and approaches are invented to investigate the stability issues, looking forward to an extra-high penetration or totally renewable resource based power systems. These analyzing...

The Power Quality Compensation Strategy for Power Distribution System Based on Hybrid Parallel Active Power Filters

Directory of Open Access Journals (Sweden)

Rachid DEHINI

2010-12-01

Full Text Available In this paper, the main aim is to confront the performance of shunt active power filter (SAPF and the shunt hybrid active power filter (SHAPF to achieve flexibility and reliability of the filter devices. Both of the two devices used the classical proportional-integral controller for pulse generation to trigger the inventers MOSFET’s. In the adopted hybrid active filter there is a passive power filter with high power rating to filter the low order harmonies and one active filter with low power rating to filter the other high order harmonies. In order to investigate the effectiveness of (SHAPF, the studies have been accomplished using simulation with the MATLAB-SIMULINK. The results show That (SHAPF is more effective than (SAPF, and has lower cost.

A Multi-Functional Power Electronic Converter in Distributed Generation Power Systems

DEFF Research Database (Denmark)

Chen, Zhe; Blaabjerg, Frede; Pedersen, John Kim

2005-01-01

of the converter interfacing a wind power generation unit is also given. The power electronic interface performs the optimal operation in the wind turbine system to extract the maximum wind power, while it also plays a key role in a hybrid compensation system that consists of the active power electronic converter......This paper presents a power electronic converter which is used as an interface for a distributed generation unit/energy storage device, and also functioned as an active power compensator in a hybrid compensation system. The operation and control of the converter have been described. An example...... and passive filters connected to each distorting load or distributed generation (DG) unit. The passive filters are distributely located to remove major harmonics and provide reactive power compensation. The active power electronic filter corrects the system unbalance, removes the remaining harmonic components...

Characteristics of self-powered neutron detectors used in power reactors

International Nuclear Information System (INIS)

Todt, W.H.

1997-01-01

Self-Powered Neutron Detectors have been used effectively as in-core flux monitors for over twenty-five years in nuclear power reactors world-wide. The basic properties of these radiation sensors are described including their nuclear, electrical and mechanical characteristics. Recommendations are given for the proper choice of the self-powered detector emitter to provide the proper response time and radiation sensitivity desired for use in an effective in-core radiation monitoring system. Examples are shown of specific self-powered detector designs which are being effectively used in in-core instrumentation systems for pressurised water, heavy water and graphite moderated light water reactors. Examples are also shown of the mechanical configurations of in-core assemblies of self-powered detectors combined with in-core thermocouples presently used in pressurised water and heavy water reactors worldwide. This paper is a summary of a new IEC standard to be issued in 1996 describing the characteristics and test methods of self-powered detectors used in nuclear power reactors. (author)

Nuclear power prospects

Energy Technology Data Exchange (ETDEWEB)

NONE

1960-09-15

A survey of the nuclear power needs of the less-developed countries and a study of the technology and economics of small and medium scale power reactors are envisioned by the General Conference. Agency makes its services available to Member States to assist them for their future nuclear power plans, and in particular in studying the technical and economic aspects of their power programs. The Agency also undertakes general studies on the economics of nuclear power, including the collection and analysis of cost data, in order to assist Member States in comparing and forecasting nuclear power costs in relation to their specific situations

Power and death: Mortality salience increases power seeking while feeling powerful reduces death anxiety.

Science.gov (United States)

Belmi, Peter; Pfeffer, Jeffrey

2016-05-01

According to Terror Management Theory, people respond to reminders of mortality by seeking psychological security and bolstering their self-esteem. Because previous research suggests that having power can provide individuals a sense of security and self-worth, we hypothesize that mortality salience leads to an increased motivation to acquire power, especially among men. Study 1 found that men (but not women) who wrote about their death reported more interest in acquiring power. Study 2A and Study 2B demonstrated that when primed with reminders of death, men (but not women) reported behaving more dominantly during the subsequent week, while both men and women reported behaving more prosocially during that week. Thus, mortality salience prompts people to respond in ways that help them manage their death anxiety but in ways consistent with normative gender expectations. Furthermore, Studies 3-5 showed that feeling powerful reduces anxiety when mortality is salient. Specifically, we found that when primed to feel more powerful, both men and women experienced less mortality anxiety. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Keys to success for wind power in isolated power systems

Energy Technology Data Exchange (ETDEWEB)

Hansen, J C; Lundsager, P; Bindner, H; Hansen, L; Frandsen, S [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark)

1999-03-01

It is generally expected that wind power could contribute significantly to the electricity supply in power systems of small and medium sized isolated communities. The market for such applications of wind power has not yet materialized. Wind power in isolated power systems have the main market potentials in developing countries. The money available world-wide for this technological development is limited and the necessary R and D and pilot programmes have difficult conditions. Consequently, technology developed exclusively for developing countries rarely becomes attractive for consumers, investors and funding agencies. A Danish research project is aimed at studying development of methods and guidelines rather than `universal solutions` for the use of wind energy in isolated communities. This paper report on the findings of the project regarding barriers removal and engineering methods development, with a focus on analysis and specification of user demand and priorities, numerical modeling requirements as well as wind power impact on power quality and power system operation. Input will be provided on these subjects for establishing of common guidelines on relevant technical issues, and thereby enabling the making of trustworthy project preparation studies. (au) EFP-97. 12 refs.

Power generation and power system development for the period after 2000

International Nuclear Information System (INIS)

Fushtikj, Vangel

1998-01-01

The paper presents an overview of the power generation and power system development worldwide in terms of forecast power and energy production. The conditions of power system ability to meet the changes, caused by the new technologies development and regulatory policy, in the next intensive energy period are also considered. Identified key issues are used to emphasize the guided concepts and principles in power system evolution. (Author)

Personal power systems

Energy Technology Data Exchange (ETDEWEB)

Dunn-Rankin, Derek; Leal, Elisangela Martins; Walther, David C. [Mechanical and Aerospace Engineering Department, University of California, Irvine, CA 92697 (United States)

2005-07-01

The lack of compact, efficient, human compatible, lightweight power sources impedes the realization of machine-enhanced human endeavor. Electronic and communication devices, as well as mobile robotic devices, need new power sources that will allow them to operate autonomously for periods of hours. In this work, a personal power system implies an application of interest to an individual person. The human-compatible gravimetric energy density spans the range from 500 to 5000Wh/kg, with gravimetric power density requirements from 10 to 1000W/kg. These requirements are the primary goals for the systems presented here. The review examines the interesting and promising concepts in electrochemical, thermochemical, and biochemical approaches to small-scale power, as well as their technological and physical challenges and limitations. Often it is the limitations that dominate, so that while the technology to create personal autonomy for communications, information processing and mobility has accelerated, similar breakthroughs for the systems powering these devices have not yet occurred. Fuel cells, model airplane engines, and hummingbird metabolism, are three promising examples, respectively, of electrochemical, thermochemical, and biochemical power production strategies that are close to achieving personal power systems' power demands. Fuel cells show great promise as an energy source when relatively low power density is demanded, but they cannot yet deliver high peak powers nor respond quickly to variable loads. Current small-scale engines, while achieving extraordinary power densities, are too inefficient to achieve the energy density needed for long-duration autonomous operation. Metabolic processes of flying insects and hummingbirds are remarkable biological energy converters, but duplicating, accelerating, and harnessing such power for mobility applications is virtually unexplored. These challenges are significant, and they provide a fertile environment for

The end of cheap electric power from nuclear power plants. 2. ed.

International Nuclear Information System (INIS)

Franke, J.; Viefhues, D.

1984-04-01

The economic efficiency of a nuclear power plant is compared with that of a coal-fired power plant of the same size. A technical and economic computer model was developed which took account of the power plant and all its units as well as the fuel cycle (including intermediate storage and reprocessing). It was found that future nuclear power plants will be inferior to coal-fired power plants in all economic respects. Further, there was no load range in which the cost of electric power generation was more favourable in nuclear power plants than in coal-fired power plants. (orig./HSCH) [de

Dynamic impedance compensation for wireless power transfer using conjugate power

Science.gov (United States)

Liu, Suqi; Tan, Jianping; Wen, Xue

2018-02-01

Wireless power transfer (WPT) via coupled magnetic resonances has been in development for over a decade. However, the frequency splitting phenomenon occurs in the over-coupled region. Thus, the output power of the two-coil system achieves the maximum output power at the two splitting angular frequencies, and not at the natural resonant angular frequency. According to the maximum power transfer theorem, the impedance compensation method was adopted in many WPT projects. However, it remains a challenge to achieve the maximum output power and transmission efficiency in a fixed-frequency mode. In this study, dynamic impedance compensation for WPT was presented by utilizing the compensator within a virtual three-coil WPT system. First, the circuit model was established and transfer characteristics of a system were studied by utilizing circuit theories. Second, the power superposition of the WPT system was carefully researched. When a pair of compensating coils was inserted into the transmitter loop, the conjugate power of the compensator loop was created via magnetic coupling of the two compensating coils that insert into the transmitter loop. The mechanism for dynamic impedance compensation for wireless power transfer was then provided by investigating a virtual three-coil WPT system. Finally, the experimental circuit of a virtual three-coil WPT system was designed, and experimental results are consistent with the theoretical analysis, which achieves the maximum output power and transmission efficiency.

Dynamic impedance compensation for wireless power transfer using conjugate power

Directory of Open Access Journals (Sweden)

Suqi Liu

2018-02-01

Full Text Available Wireless power transfer (WPT via coupled magnetic resonances has been in development for over a decade. However, the frequency splitting phenomenon occurs in the over-coupled region. Thus, the output power of the two-coil system achieves the maximum output power at the two splitting angular frequencies, and not at the natural resonant angular frequency. According to the maximum power transfer theorem, the impedance compensation method was adopted in many WPT projects. However, it remains a challenge to achieve the maximum output power and transmission efficiency in a fixed-frequency mode. In this study, dynamic impedance compensation for WPT was presented by utilizing the compensator within a virtual three-coil WPT system. First, the circuit model was established and transfer characteristics of a system were studied by utilizing circuit theories. Second, the power superposition of the WPT system was carefully researched. When a pair of compensating coils was inserted into the transmitter loop, the conjugate power of the compensator loop was created via magnetic coupling of the two compensating coils that insert into the transmitter loop. The mechanism for dynamic impedance compensation for wireless power transfer was then provided by investigating a virtual three-coil WPT system. Finally, the experimental circuit of a virtual three-coil WPT system was designed, and experimental results are consistent with the theoretical analysis, which achieves the maximum output power and transmission efficiency.

Stochastic reactive power dispatch in hybrid power system with intermittent wind power generation

International Nuclear Information System (INIS)

Taghavi, Reza; Seifi, Ali Reza; Samet, Haidar

2015-01-01

Environmental concerns besides fuel costs are the predominant reasons for unprecedented escalating integration of wind turbine on power systems. Operation and planning of power systems are affected by this type of energy due to the intermittent nature of wind speed inputs with high uncertainty in the optimization output variables. Consequently, in order to model this high inherent uncertainty, a PRPO (probabilistic reactive power optimization) framework should be devised. Although MC (Monte-Carlo) techniques can solve the PRPO with high precision, PEMs (point estimate methods) can preserve the accuracy to attain reasonable results when diminishing the computational effort. Also, this paper introduces a methodology for optimally dispatching the reactive power in the transmission system, while minimizing the active power losses. The optimization problem is formulated as a LFP (linear fuzzy programing). The core of the problem lay on generation of 2m + 1 point estimates for solving PRPO, where n is the number of input stochastic variables. The proposed methodology is investigated using the IEEE-14 bus test system equipped with HVDC (high voltage direct current), UPFC (unified power flow controller) and DFIG (doubly fed induction generator) devices. The accuracy of the method is demonstrated in the case study. - Highlights: • This paper uses stochastic loads in optimization process. • AC–DC load flow is modified to use some advantages of DC part in optimization process. • UPFC and DFIG are simulated in a way that could be effective in optimization process. • Fuzzy set has been used as an uncertainty analysis tool in the optimization

Optimal Power Flow Control by Rotary Power Flow Controller

Directory of Open Access Journals (Sweden)

KAZEMI, A.

2011-05-01

Full Text Available This paper presents a new power flow model for rotary power flow controller (RPFC. RPFC injects a series voltage into the transmission line and provides series compensation and phase shifting simultaneously. Therefore, it is able to control the transmission line impedance and the active power flow through it. An RPFC is composed mainly of two rotary phase shifting transformers (RPST and two conventional (series and shunt transformers. Structurally, an RPST consists of two windings (stator and rotor windings. The rotor windings of the two RPSTs are connected in parallel and their stator windings are in series. The injected voltage is proportional to the vector sum of the stator voltages and so its amplitude and angle are affected by the rotor position of the two RPSTs. This paper, describes the steady state operation and single-phase equivalent circuit of the RPFC. Also in this paper, a new power flow model, based on power injection model of flexible ac transmission system (FACTS controllers, suitable for the power flow analysis is introduced. Proposed model is used to solve optimal power flow (OPF problem in IEEE standard test systems incorporating RPFC and the optimal settings and location of the RPFC is determined.

Scheduling of Power System Cells Integrating Stochastic Power Generation

International Nuclear Information System (INIS)

Costa, L.M.

2008-12-01

Energy supply and climate change are nowadays two of the most outstanding problems which societies have to cope with under a context of increasing energy needs. Public awareness of these problems is driving political willingness to take actions for tackling them in a swift and efficient manner. Such actions mainly focus in increasing energy efficiency, in decreasing dependence on fossil fuels, and in reducing greenhouse gas emissions. In this context, power systems are undergoing important changes in the way they are planned and managed. On the one hand, vertically integrated structures are being replaced by market structures in which power systems are un-bundled. On the other, power systems that once relied on large power generation facilities are witnessing the end of these facilities' life-cycle and, consequently, their decommissioning. The role of distributed energy resources such as wind and solar power generators is becoming increasingly important in this context. However, the large-scale integration of such type of generation presents many challenges due, for instance, to the uncertainty associated to the variability of their production. Nevertheless, advanced forecasting tools may be combined with more controllable elements such as energy storage devices, gas turbines, and controllable loads to form systems that aim to reduce the impacts that may be caused by these uncertainties. This thesis addresses the management under market conditions of these types of systems that act like independent societies and which are herewith named power system cells. From the available literature, a unified view of power system scheduling problems is also proposed as a first step for managing sets of power system cells in a multi-cell management framework. Then, methodologies for performing the optimal day-ahead scheduling of single power system cells are proposed, discussed and evaluated under both a deterministic and a stochastic framework that directly integrates the

Reactor power control device

International Nuclear Information System (INIS)

Ishii, Yoshihiko; Arita, Setsuo; Miyamoto, Yoshiyuki; Fukazawa, Yukihisa; Ishii, Kazuhiko

1998-01-01

The present invention provides a reactor power control device capable of enhancing an operation efficiency while keeping high reliability and safety in a BWR type nuclear power plant. Namely, the device of the present invention comprises (1) a means for inputting a set value of a generator power and a set value of a reactor power, (2) a means for controlling the reactor power to either smaller one of the reactor power corresponding to the set value of the generator power and the set value of the reactor power. With such procedures, even if the nuclear power plant is set so as to operate it to make the reactor power 100%, when the generator power reaches the upper limit, the reactor power is controlled with a preference given to the upper limit value of the generator power. Accordingly, safety and reliability are not deteriorated. The operation efficiency of the plant can be improved. (I.S.)

Power, right, and truth: Foucault's triangle as a model for clinical power.

Science.gov (United States)

Polifroni, E Carol

2010-01-01

Power has historically been viewed from a position of dominance and authority. Using this lens leads one to a destiny wherein one individual or society has power over another. The power over approach is a hierarchical view, one that leads to someone else being oppressed, and one wherein the prevailing hegemony continues. If a different lens is used, wherein power does not reside within a position, but rather, within a person and within a relationship bounded by knowledge, a new destiny of power to and power of is created. These two approaches to power are examined and clinical power is offered as a lens that culminates in the understanding of power as a right and as truth imbedded with awareness and relationships.

Are atomic power plants saver than nuclear power plants

International Nuclear Information System (INIS)

Roeglin, H.C.

1977-01-01

It is rather impossible to establish nuclear power plants against the resistance of the population. To prevail over this resistance, a clarification of the citizens-initiatives motives which led to it will be necessary. This is to say: It is quite impossible for our population to understand what really heappens in nuclear power plants. They cannot identify themselves with nuclear power plants and thus feel very uncomfortable. As the total population feels the same way it is prepared for solidarity with the citizens-initiatives even if they believe in the necessity of nuclear power plants. Only an information-policy making transparent the social-psychological reasons of the population for being against nuclear power plants could be able to prevail over the resistance. More information about the technical procedures is not sufficient at all. (orig.) [de

Fusion-power demonstration

International Nuclear Information System (INIS)

Henning, C.D.; Logan, B.G.; Carlson, G.A.; Neef, W.S.; Moir, R.W.; Campbell, R.B.; Botwin, R.; Clarkson, I.R.; Carpenter, T.J.

1983-01-01

As a satellite to the MARS (Mirror Advanced Reactor Study) a smaller, near-term device has been scoped, called the FPD (Fusion Power Demonstration). Envisioned as the next logical step toward a power reactor, it would advance the mirror fusion program beyond MFTF-B and provide an intermediate step toward commercial fusion power. Breakeven net electric power capability would be the goal such that no net utility power would be required to sustain the operation. A phased implementation is envisioned, with a deuterium checkout first to verify the plasma systems before significant neutron activation has occurred. Major tritium-related facilities would be installed with the second phase to produce sufficient fusion power to supply the recirculating power to maintain the neutral beams, ECRH, magnets and other auxiliary equipment

Fusion power demonstration

International Nuclear Information System (INIS)

Henning, C.D.; Logan, B.G.

1983-01-01

As a satellite to the MARS (Mirror Advanced Reactor Study) a smaller, near-term device has been scoped, called the FPD (Fusion Power Demonstration). Envisioned as the next logical step toward a power reactor, it would advance the mirror fusion program beyond MFTF-B and provide an intermediate step toward commercial fusion power. Breakeven net electric power capability would be the goal such that no net utility power would be required to sustain the operation. A phased implementation is envisioned, with a deuterium checkout first to verify the plasma systems before significant neutron activation has occurred. Major tritium-related facilities would be installed with the second phase to produce sufficient fusion power to supply the recirculating power to maintain the neutral beams, ECRH, magnets and other auxiliary equipment

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

Directory of Open Access Journals (Sweden)

V. N. Radkevich

2016-01-01

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

High power communication satellites power systems study

International Nuclear Information System (INIS)

Josloff, A.T.; Peterson, J.R.

1994-01-01

This paper discusses a DOE-funded study to evaluate the commercial attractiveness of high power communication satellites and assesses the attributes of both conventional photovoltaic and reactor power systems. This study brings together a preeminent US Industry/Russian team to cooperate on the role of high power communication satellites in the rapidly expanding communications revolution. These high power satellites play a vital role in assuring availability of universally accessible, wide bandwidth communications, for high definition TV, super computer networks and other services. Satellites are ideally suited to provide the wide bandwidths and data rates required and are unique in the ability to provide services directly to the users. As new or relocated markets arise, satellites offer a flexibility that conventional distribution services cannot match, and it is no longer necessary to be near population centers to take advantage of the telecommunication revolution. The geopolitical implications of these substantially enhanced communications capabilities will be significant

Impact of wind power in autonomous power systems—power fluctuations—modelling and control issues

DEFF Research Database (Denmark)

Margaris, Ioannis D.; Hansen, Anca Daniela; Cutululis, Nicolaos Antonio

2011-01-01

for diesel and steam generation plants are applied. The power grid, including speed governors, automatic voltage regulators, protection system and loads is modelled in the same platform. Results for different load and wind profile cases are being presented for the case study of the island Rhodes, in Greece......This paper describes a detailed modelling approach to study the impact of wind power fluctuations on the frequency control in a non-interconnected system with large-scale wind power. The approach includes models for wind speed fluctuations, wind farm technologies, conventional generation...... technologies, power system protection and load. Analytical models for wind farms with three different wind turbine technologies, namely Doubly Fed Induction Generator, Permanent Magnet Synchronous Generator and Active Stall Induction Generator-based wind turbines, are included. Likewise, analytical models...

Potassium Rankine cycle power conversion systems for lunar-Mars surface power

International Nuclear Information System (INIS)

Holcomb, R.S.

1992-01-01

The potassium Rankine cycle has good potential for application to nuclear power systems for surface power on the moon and Mars. A substantial effort on the development of the power conversion system was carried out in the 1960's which demonstrated successful operation of components made of stainless steel at moderate temperatures. This technology could be applied in the near term to produce a 360 kW(e) power system by coupling a stainless steel power conversion system to the SP-100 reactor. Improved performance could be realized in later systems by utilizing niobium or tantalum refractory metal alloys in the reactor and power conversion system. The design characteristics and estimated mass of power systems for each of three technology levels are presented in the paper

Towards passive house standards in school buildings. Maela smart building - final report; Mot passivhusstandard i undervisningsbygg. Maela smartbygg - sluttrapport

Energy Technology Data Exchange (ETDEWEB)

Wachenfeldt, Bjoern Jenssen; Dokka, Tor Helge

2008-07-01

SINTEF has in cooperation with the projecting group for Maela School, worked towards smart and general concepts to achieve good comfort with low energy consumption, low environmental impact and low investments. The project is called 'Maela smart building'. Based on conceptual solutions chosen for Maela School, this might be one of the leading school buildings in concern of energy efficiency. To be sure of achieving the target of needed energy to be less than 80 kWh/m{sub 2}, this assumes that the solutions satisfies the demands elaborated with basis in the energy target for the building together with heating and ventilation technical outfit run optimally. If the real consumption shall decrease towards calculated energy needs, the users have to be conscious not to contribute in wasting energy. Further the management of heat and ventilation has to function optimally, the setpoint for heating and ventilation has to be precise. In addition the operators have to have insight in how a building like this functions and the right skills to run it correct. Emphasis on alternatives contributing positively to architecture and good indoor environment in addition to focus on energy efficiency were considered for technical designing of the conceptual heat and ventilation solutions. Generally the need for ventilation channels is reduced to a minimum and the mechanical ventilation is dimensioned considering air quality. Thermic comfort is secured by means of passive attempt such as natural ventilation, sun screening and exploitation of thermic substance in ceiling, walls and floor. Choice of windows and walls with translucent isolation implied some increased risk for overheated teaching wings in second floor in warm and sunny periods. Since these premises because of school vacation in summer, normally is not in use in the summer, the attempts such as sun screening, natural ventilation and night cooling (ventilation of surplus heat during nights),were considered sufficient

Cost-effectiveness of low-power nuclear power plants

International Nuclear Information System (INIS)

Mitenkov, F.M.; Vostokov, V.S.; Drozhkin, V.N.; Samoilov, O.B.

1994-01-01

Many potential consumers of electricity and heat, consuming several thousands of kilowatts (up to 10-15 MW), have now been identified. This is significant primarily for regions far from power grids and other centralized sources of energy, such as, for example, Yakutiya, Northeastern Siberia, and elsewhere. These consumers are now supplied with fossil fuel, which is often difficult and expensive to deliver. For this reason it is very important to develop low-power nuclear power plants for remote regions

Wind Power Now!

Science.gov (United States)

Inglis, David Rittenhouse

1975-01-01

The government promotes and heavily subsidizes research in nuclear power plants. Federal development of wind power is slow in comparison even though much research with large wind-electric machines has already been conducted. Unless wind power programs are accelerated it will not become a major energy alternative to nuclear power. (MR)

Human Powered Centrifuge

Science.gov (United States)

Mulenburg, Gerald M. (Inventor); Vernikos, Joan (Inventor)

1997-01-01

A human powered centrifuge has independently established turntable angular velocity and human power input. A control system allows excess input power to be stored as electric energy in a battery or dissipated as heat through a resistors. In a mechanical embodiment, the excess power is dissipated in a friction brake.

Coupled energy and reactive power market clearing considering power system security

International Nuclear Information System (INIS)

Rabiee, Abdorreza; Shayanfar, Heidarali; Amjady, Nima

2009-01-01

In a deregulated environment, when talking about electricity markets, one usually refers to energy market, paying less attention to the reactive power market. Active and reactive powers are, however, coupled through the AC power flow equations and branch loading limits as well as the synchronous generators capability curves. However, the sequential approach for energy and reactive power markets cannot present the optimal solution due to the interactions between these markets. For instance, clearing of the reactive power market can change active power dispatch (e.g. due to a change of transmission system losses and the capability curve limitation), which can lead to degradation of the energy market clearing point. This paper presents a coupled day ahead energy and reactive power market based on the pay-at-MCP settlement mechanism. Besides, the proposed coupled framework considers voltage stability and security issues and branch loading limits. The coupled market is cleared through optimal power flow (OPF). Its objective function includes total payment of generating units for their active power production along with the total payment function (TPF) of units for their reactive power compensation. Moreover, lost opportunity cost (LOC) of the units is also considered. The effectiveness of the proposed framework is examined on the IEEE 24 bus Reliability Test System

Coupled energy and reactive power market clearing considering power system security

Energy Technology Data Exchange (ETDEWEB)

Rabiee, Abdorreza; Shayanfar, Heidarali [Center of Excellence for Power System Automation and Operation, Electrical Engineering Department, Iran University of Science and Technology (IUST), Tehran (Iran); Amjady, Nima [Department of Electrical Engineering, Semnan University, Semnan (Iran)

2009-04-15

In a deregulated environment, when talking about electricity markets, one usually refers to energy market, paying less attention to the reactive power market. Active and reactive powers are, however, coupled through the AC power flow equations and branch loading limits as well as the synchronous generators capability curves. However, the sequential approach for energy and reactive power markets cannot present the optimal solution due to the interactions between these markets. For instance, clearing of the reactive power market can change active power dispatch (e.g. due to a change of transmission system losses and the capability curve limitation), which can lead to degradation of the energy market clearing point. This paper presents a coupled day ahead energy and reactive power market based on the pay-at-MCP settlement mechanism. Besides, the proposed coupled framework considers voltage stability and security issues and branch loading limits. The coupled market is cleared through optimal power flow (OPF). Its objective function includes total payment of generating units for their active power production along with the total payment function (TPF) of units for their reactive power compensation. Moreover, lost opportunity cost (LOC) of the units is also considered. The effectiveness of the proposed framework is examined on the IEEE 24 bus Reliability Test System. (author)

Comparative studies between nuclear power plants and hydroelectric power plants

International Nuclear Information System (INIS)

Menegassi, J.

1984-01-01

This paper shows the quantitative evolution of the power plants in the main countries of the world. The Brazilian situation is analysed, with emphasys in the technical and economical aspects related to power production by hidroelectric or nuclear power plants. The conclusion is that the electricity produced by hidro power plants becomes not economics when is intended to be produced at large distances from the demand centers. (Author) [pt

UPWARD POWER TENDENCIES IN A HIERARCHY - POWER DISTANCE THEORY VERSUS BUREAUCRATIC RULE

NARCIS (Netherlands)

WILKE, HAM

1993-01-01

Two contrasting notions concerning upward power tendencies within hierarchically structured groups are investigated. Power Distance Theory assumes that people have a desire for power that results in a tendency to reduce the power distance towards a more powerful other, and this tendency is assumed

Power monitors: A framework for system-level power estimation using heterogeneous power models

NARCIS (Netherlands)

Bansal, N.; Lahiri, K.; Raghunathan, A.; Chakradhar, S.T.

2005-01-01

Paper analysis early in the design cycle is critical for the design of low-power systems. With the move to system-level specifications and design methodologies, there has been significant research interest in system-level power estimation. However, as demonstrated in this paper, the addition of

Modern nuclear power-green power of the millennium

International Nuclear Information System (INIS)

Biswas, R.N.

2003-01-01

In India, as well as many developing countries, the demand for power continues to race ahead of the supply position. Our present generating capacity of about 1,08,000 MW needs to be increased by another 1 lac MW during 10th and 11th 5-year plans. Whereas more friendly renewable energy may reach about 10-12%, the rest has to come from conventional thermal, hydel or nuclear energy. Thermal energy actually needs low investment per MW but it is the least eco-friendly. Hydel power is green and clean power but the actual energy generated depends on the water quantity available, hence not fully dependable. Therefore in short, nuclear energy available in abundance, has no option for meeting the increasing base demand, as has been proved in Britain, USA, France, Japan and other countries. This paper gives the latest improvements in nuclear power plant design and construction for improved efficiency, operating safety and safe waste storage facilities and explains that nuclear power is affordable and indispensable

Smart power. Great leaders know when hard power is not enough.

Science.gov (United States)

Nye, Joseph S

2008-11-01

The next U.S. administration will face enormous challenges to world peace, the global economy, and the environment. Exercising military and economic muscle alone will not bring peace and prosperity. According to Nye, a former U.S. government official and a former dean at Harvard University's John F. Kennedy School of Government, the next president must be able to combine hard power, characterized by coercion, and what Nye calls "soft" power, which relies instead on attraction. The result is smart power, a tool great leaders use to mobilize people around agendas that look beyond current problems. Hard power is often necessary, Nye explains. In the 1990s, when the Taliban was providing refuge to Al Oaeda, President Clinton tried---and failed--to solve the problem diplomatically instead of destroying terrorist havens in Afghanistan. In other situations, however, soft power is more effective, though it has been too often overlooked. In Iraq, Nye argues, the use of soft power could draw young people toward something other than terrorism. "I think that there's an awakening to the need for soft power as people look at the crisis in the Middle East and begin to realize that hard power is not sufficient to resolve it," he says. Solving today's global problems will require smart power--a judicious blend of the other two powers. While there are notable examples of men who have used smart power--Teddy Roosevelt, for instance--it's much more difficult for women to lead with smart power, especially in the United States, where women feel pressure to prove that they are not "soft." Only by exercising smart power, Nye says, can the next president of the United States set a new tone for U.S. foreign policy in this century.

Wind power

International Nuclear Information System (INIS)

Gipe, P.

2007-01-01

This book is a translation of the edition published in the USA under the title of ''wind power: renewable energy for home, farm and business''. In the wake of mass blackouts and energy crises, wind power remains a largely untapped resource of renewable energy. It is a booming worldwide industry whose technology, under the collective wing of aficionados like author Paul Gipe, is coming of age. Wind Power guides us through the emergent, sometimes daunting discourse on wind technology, giving frank explanations of how to use wind technology wisely and sound advice on how to avoid common mistakes. Since the mid-1970's, Paul Gipe has played a part in nearly every aspect of wind energy development from installing small turbines to promoting wind energy worldwide. As an American proponent of renewable energy, Gipe has earned the acclaim and respect of European energy specialists for years, but his arguments have often fallen on deaf ears at home. Today, the topic of wind power is cropping up everywhere from the beaches of Cape Cod to the Oregon-Washington border, and one wind turbine is capable of producing enough electricity per year to run 200 average American households. Now, Paul Gipe is back to shed light on this increasingly important energy source with a revised edition of Wind Power. Over the course of his career, Paul Gipe has been a proponent, participant, observer, and critic of the wind industry. His experience with wind has given rise to two previous books on the subject, Wind Energy Basics and Wind Power for Home and Business, which have sold over 50,000 copies. Wind Power for Home and Business has become a staple for both homeowners and professionals interested in the subject, and now, with energy prices soaring, interest in wind power is hitting an all-time high. With chapters on output and economics, Wind Power discloses how much you can expect from each method of wind technology, both in terms of energy and financial savings. The book updated models

Routing power flows in distribution networks using locally controlled power electronics

NARCIS (Netherlands)

Hamelink, J.; Nguyen, P.H.; Kling, W.L.; Ribeiro, P.F.; Groot, de R.J.W.

2012-01-01

The power grid has gradually changed its operation during the recent decades. These developments have encouraged a shift from centralized to decentralized power flow control. A research has been carried out to investigate the possibilities to control power flows using the Smart Power Router (SPR) in

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

CERN Document Server

Revuelta, Patricio Salmeron; Litrán, Salvador Pérez

2015-01-01

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

Multi-port power router and its impact on resilient power grid systems

Science.gov (United States)

Kado, Yuichi; Iwatsuki, Katsumi; Wada, Keiji

2016-02-01

We propose a Y-configuration power router as a unit cell to easily construct a power delivery system that can meet many types of user requirements. The Y-configuration power router controls the direction and magnitude of power flow among three ports regardless of DC and AC. We constructed a prototype three-way isolated DC/DC converter that is the core unit of the Y-configuration power router and tested the power flow control operation. Experimental results revealed that our methodology based on the governing equation was appropriate for the power flow control of the three-way DC/DC converter. In addition, the hexagonal distribution network composed of the power routers has the ability to easily interchange electric power between autonomous microgrid cells. We also explored the requirements for communication between energy routers to achieve dynamic adjustments of energy flow in a coordinated manner and its impact on resilient power grid systems.

Power uprates in nuclear power plants: international experiences and approaches for implementation

International Nuclear Information System (INIS)

Kang, Ki Sig

2008-01-01

The greater demand for electricity and the available capacity within safety margins in some operating NPPs are prompting nuclear utilities to request license modification to enable operation at a higher power level, beyond their original license provisions. Such plant modifications require an in-depth safety analysis to evaluate the possible safety impact. The analysis must consider the thermo hydraulic, radiological and structural aspects, and the plant behavior, while taking into account the capability of the structures, systems and components, and the reactor protection and safeguard systems set points. The purpose of this paper is to introduce international experiences and approaches for implementation of power uprates related to the reactor thermal power of nuclear power plants. The paper is intended to give the reader a general overview of the major processes, work products, issues, challenges, events, and experiences in the power uprates program. The process of increasing the licensed power level of a nuclear power plants is called a power uprate. One way of increasing the thermal output from a reactor is to increase the amount of fissile material in use. It is also possible to increase the core power by increasing the performance of the high power bundles. Safety margins can be maintained by either using fuels with a higher performance, or through the use of improved methods of analysis to demonstrate that the required margins are retained even at the higher power levels. The paper will review all types of power uprates, from small to large, and across various reactor types, including light and heavy water, pressurized, and boiling water reactors. Generally, however, the content of the report focuses on power uprates of the stretch and extended type. The International Atomic Energy Agency (IAEA) is developing a technical guideline on power uprates and side effects of power uprates in nuclear power plants

Applications of power beaming from space-based nuclear power stations

International Nuclear Information System (INIS)

Powell, J.R.; Botts, T.E.; Hertzberg, A.

1981-01-01

Power beaming from space-based reactor systems is examined using an advanced compact, lightweight Rotating Bed Reactor (RBR). Closed Brayton power conversion efficiencies in the range of 30 to 40% can be achieved with turbines, with reactor exit temperatures on the order of 2000 0 K and a liquid drop radiator to reject heat at temperatures of approx. 500 0 K. Higher RBR coolant temperatures (up to approx. 3000 0 K) are possible, but gains in power conversion efficiency are minimal, due to lower expander efficiency (e.g., a MHD generator). Two power beaming applications are examined - laser beaming to airplanes and microwave beaming to fixed ground receivers. Use of the RBR greatly reduces system weight and cost, as compared to solar power sources. Payback times are a few years at present prices for power and airplane fuel

Mitigation of Power System Oscillation Caused by Wind Power Fluctuation

DEFF Research Database (Denmark)

Su, Chi; Hu, Weihao; Chen, Zhe

2013-01-01

oscillation mitigation controllers are proposed and compared. A model of direct-drive-full-convertor-based wind farm connected to the IEEE 10-machine 39-bus system is adopted as the test system. The calculations and simulations are conducted in DIgSILENT PowerFactory 14.0. Results are presented to show......Wind power is increasingly integrated in modern power grids, which brings new challenges to the power system operation. Wind power is fluctuating because of the uncertain nature of wind, whereas wind shear and tower shadow effects also cause periodic fluctuations. These may lead to serious forced...... oscillation when the frequencies of the periodic fluctuations are close to the natural oscillation frequencies of the connected power system. By using modal analysis and time-domain simulations, this study studies the forced oscillation caused by the wind shear and tower shadow effects. Three forced...

Financing of nuclear power plant using resources of power generation

International Nuclear Information System (INIS)

Slechta, V.; Milackova, H.

1987-01-01

It is proved that during the lifetime of a power plant, financial resources are produced from depreciation and from the profit for the delivered electrical power in an amount allowing to meet the cost of construction, interests of credits, the corporation taxes, and the means usable by the utility for simple reproduction of the power plant, additional investment, or for the ultimate decommissioning of the nuclear power plant. The considerations are simplified to 1 MW of installed capacity of a WWER-440 nuclear power plant. The breakdown is shown of the profit and the depreciation over the power plant lifetime, the resources of regular payments of credit instalments for the construction and the method of its calculation, and the income for the state budget and for the utility during the plant liofetime. (J.B.). 5 tabs., 5 refs

Multiobjective clearing of reactive power market in deregulated power systems

International Nuclear Information System (INIS)

Rabiee, A.; Shayanfar, H.; Amjady, N.

2009-01-01

This paper presents a day-ahead reactive power market which is cleared in the form of multiobjective context. Total payment function (TPF) of generators, representing the payment paid to the generators for their reactive power compensation, is considered as the main objective function of reactive power market. Besides that, voltage security margin, overload index, and also voltage drop index are the other objective functions of the optimal power flow (OPF) problem to clear the reactive power market. A Multiobjective Mathematical Programming (MMP) formulation is implemented to solve the problem of reactive power market clearing using a fuzzy approach to choose the best compromise solution according to the specific preference among various non-dominated (pareto optimal) solutions. The effectiveness of the proposed method is examined based on the IEEE 24-bus reliability test system (IEEE 24-bus RTS). (author)

Employing modern power plant simulators in nuclear power plants

International Nuclear Information System (INIS)

Niedorf, V.; Storm, J.

2005-01-01

At the present state of the art, modern power plant simulators are characterized by new qualitative features, thus enabling operators to use them far beyond the traditional field of training. In its first part, this contribution presents an overview of the requirements to be met by simulators for multivalent uses. In part two, a survey of the uses and perspectives of simulation technology in power plants is presented on the basis of experience accumulated by Rheinmetall Defence Electronics (RDE).Modern simulators are shown to have applications by far exceeding traditional training areas. Modular client - sever systems on standard computers allow inexpensive uses to be designed at several levels, thus minimizing maintenance cost. Complex development and running time environments, like the SEMS developed by RDE, have made power plant simulators the workhorses of power plant engineers in all power plant areas. (orig.)

Power Oscillation Damping from VSC-HVDC Connected Offshore Wind Power Plants

DEFF Research Database (Denmark)

Zeni, Lorenzo; Eriksson, Robert; Goumalatsos, Spyridon

2016-01-01

The implementation of power oscillation damping service on offshore wind power plants connected to onshore grids by voltage-source-converter-based high voltage direct current transmission is discussed. Novel design guidelines for damping controllers on voltage-source converters and wind power plant...... regarding real wind power plants are discussed: 1) robustness against control/communication delays; 2) limitations due to mechanical resonances in wind turbine generators; 3) actual capability of wind power plants to provide damping without curtailing production; and 4) power-ramp rate limiters....... controllers are derived, using phasor diagrams and a test network model and are then verified on a generic power system model. The effect of voltage regulators is analyzed, which is important for selecting the most robust damping strategy. Furthermore, other often disregarded practical implementation aspects...

Distributed Power System Virtual Inertia Implemented by Grid-Connected Power Converters

DEFF Research Database (Denmark)

Fang, Jingyang; Li, Hongchang; Tang, Yi

2018-01-01

Renewable energy sources (RESs), e.g. wind and solar photovoltaics, have been increasingly used to meet worldwide growing energy demands and reduce greenhouse gas emissions. However, RESs are normally coupled to the power grid through fast-response power converters without any inertia, leading...... to decreased power system inertia. As a result, the grid frequency may easily go beyond the acceptable range under severe frequency events, resulting in undesirable load-shedding, cascading failures, or even large-scale blackouts. To address the ever-decreasing inertia issue, this paper proposes the concept...... of distributed power system virtual inertia, which can be implemented by grid-connected power converters. Without modifications of system hardware, power system inertia can be emulated by the energy stored in the dc-link capacitors of grid-connected power converters. By regulating the dc-link voltages...

Environmental Assessment for power marketing policy for Southwestern Power Administration

Energy Technology Data Exchange (ETDEWEB)

1993-12-01

Southwestern Power Administration (Southwestern) needs to renew expiring power sales contracts with new term (10 year) sales contracts. The existing contracts have been in place for several years and many will expire over the next ten years. Southwestern completed an Environmental Assessment on the existing power allocation in June, 1979 (a copy of the EA is attached), and there are no proposed additions of any major new generation resources, service to discrete major new loads, or major changes in operating parameters, beyond those included in the existing power allocation. Impacts from a no action plan, proposed alternative, and market power for less than 10 years are described.

Environmental Assessment for power marketing policy for Southwestern Power Administration

International Nuclear Information System (INIS)

1993-01-01

Southwestern Power Administration (Southwestern) needs to renew expiring power sales contracts with new term (10 year) sales contracts. The existing contracts have been in place for several years and many will expire over the next ten years. Southwestern completed an Environmental Assessment on the existing power allocation in June, 1979 (a copy of the EA is attached), and there are no proposed additions of any major new generation resources, service to discrete major new loads, or major changes in operating parameters, beyond those included in the existing power allocation. Impacts from a no action plan, proposed alternative, and market power for less than 10 years are described

Nuclear power generation incorporating modern power system practice

CERN Document Server

Myerscough, PB

1992-01-01

Nuclear power generation has undergone major expansion and developments in recent years; this third edition contains much revised material in presenting the state-of-the-art of nuclear power station designs currently in operation throughout the world. The volume covers nuclear physics and basic technology, nuclear station design, nuclear station operation, and nuclear safety. Each chapter is independent but with the necessary technical overlap to provide a complete work on the safe and economic design and operation of nuclear power stations.

Power beaming providing a space power infrastructure

International Nuclear Information System (INIS)

Bamberger, J.A.; Coomes, E.P.

1992-01-01

This paper, based on two levels of technology maturity, applied the power beaming concept to four panned satellite constellations. The analysis shows that with currently available technology, power beaming can provide mass savings to constellations in orbits ranging from low-Earth orbit to geosynchronous orbit. Two constellations, space surveillance and tracking system and space-based radar, can be supported with current technology. The other two constellations, space-based laser array and boost surveillance and tracking system, will require power and transmission system improvements before their breakeven specific mass is achieved. A doubling of SP-100 conversion efficiency from 10 to 20% would meet or exceed breakeven for these constellations

Studies on silicone based antifoaming agents to be used in G.S. (Girlder sulfide) heavy water plants

International Nuclear Information System (INIS)

Delfino, C.A.

1986-01-01

In Girlder sulfide (G.S.) heavy water plants hydrogen sulfide-water systems are inherentely foaming, so the adding of antifoaming materials is of great importance. These may be of high volatility, pyrolizable or chemically unstable in plant operation conditions (water and hydrogen sulfide at 2MPa, up to 230 deg C). Six commercial silicone based antifoaming agents were studied from the point of view of their chemical and thermical stability in order to select the most suitable. (Author) [es

Time-of-flight spectrometer for slow neutrons in use at the reactor in Saclay. Its application for the study of the inelastic diffusion of cold neutrons; L'appareillage de spectrometrie a temps-de-vol pour neutrons lents en service a la pile de Saclay. Son application a l'etude de la diffusion inelastique des neutrons froids

Energy Technology Data Exchange (ETDEWEB)

Jacsot, B; Netter, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Galula, M [Centre National de la Recherche Scientifique (CNRS), 91 - Gif-sur-Yvette (France)

1955-07-01

The time-of-flight spectrometers is constituted of a mechanic swivel obturator which absorbs neutrons until energies above 1 KeV, a mechanic filter which allow to retain only high wave length components and a delayed pulses selector with 100 channels. Its main application field is the thermic region where it allowed to measure the inelastic scattering of neutrons using various materials as H{sub 2}O, D{sub 2}O, Be, BeO, etc... (M.P.)

Impact of Poultry Litter Cake, Cleanout, and Bedding following Chemical Amendments on Soil C and N Mineralization

OpenAIRE

Watts, Dexter B.; Smith, Katy E.; Torbert, H. A.

2012-01-01

Poultry litter is a great alternative N source for crop production. However, recent poultry litter management changes, and increased chemical amendment use may impact its N availability. Thus, research was initiated to evaluate the effect that broiler cake and total cleanout litter amended with chemical additives have on C and N mineralization. A 35-day incubation study was carried out on a Hartsells fine sandy loam (fine-loamy, siliceous, subactive, thermic Typic Hapludults) soil common to t...

Innovation of power management structure in Czechoslovakia and nuclear power

Energy Technology Data Exchange (ETDEWEB)

Cibula, M

1979-01-01

The estimate is briefly indicated of power demand in Czechoslovakia till 1990 with the objective of attaining 142 mil. tonnes of specific fuel in that year. The demand will be met from domestic resources by 49%, exports by 44.2% and nuclear power by 6.8%. A brief comparison is presented of capital and fuel costs of brown coal fired power plants, hydroelectric plants and nuclear power plants in Czechoslovakia in 1990.

Innovative use of power integrated modules for DC power supplies

DEFF Research Database (Denmark)

Ørndrup Nielsen, Rasmus; Elkiær, Alexander; Munk-Nielsen, Stig

2013-01-01

In this article several innovative ways of utilizing Power Integrated Modules (PIM) as switching device in a DC power supply are presented. PIM have advantages in compactness of design, cost and fast prototype due to easier PCB layout. A PIM converter topology is chosen and designed resulting...... in an experimental setup. Results from the setup are presented showing the feasibility of using a PIM module as almost all power semiconductors in a DC power supply....

Fusion Power Deployment

International Nuclear Information System (INIS)

Schmidt, J.A.; Ogden, J.M.

2002-01-01

Fusion power plants could be part of a future portfolio of non-carbon dioxide producing energy supplies such as wind, solar, biomass, advanced fission power, and fossil energy with carbon dioxide sequestration. In this paper, we discuss key issues that could impact fusion energy deployment during the last half of this century. These include geographic issues such as resource availability, scale issues, energy storage requirements, and waste issues. The resource needs and waste production associated with fusion deployment in the U.S. should not pose serious problems. One important feature of fusion power is the fact that a fusion power plant should be locatable within most local or regional electrical distribution systems. For this reason, fusion power plants should not increase the burden of long distance power transmission to our distribution system. In contrast to fusion power, regional factors could play an important role in the deployment of renewable resources such as wind, solar and biomass or fossil energy with CO2 sequestration. We examine the role of these regional factors and their implications for fusion power deployment

Electrical Power Conversion of River and Tidal Power Generator

Energy Technology Data Exchange (ETDEWEB)

Muljadi, Eduard; Gevorgian, Vahan; Wright, Alan; Donegan, James; Marnagh, Cian; McEntee, Jarlath

2016-11-21

As renewable generation has become less expensive during recent decades, and it becomes more accepted by the global population, the focus on renewable generation has expanded to include new types with promising future applications, such as river and tidal generation. Although the utilization of power electronics and electric machines in industry is phenomenal, the emphasis on system design is different for various sectors of industry. In precision control, robotics, and weaponry, the design emphasis is on accuracy and reliability with less concern for the cost of the final product. In energy generation, the cost of energy is the prime concern; thus, capital expenditures (CAPEX) and operations and maintenance expenditures (OPEX) are the major design objectives. This paper describes the electrical power conversion aspects of river and tidal generation. Although modern power converter control is available to control the generation side, the design was chosen on the bases of minimizing the CAPEX and OPEX; thus, the architecture is simple and modular for ease of replacement and maintenance. The power conversion is simplified by considering a simple diode bridge and a DC-DC power converter to take advantage of abundant and low-cost photovoltaic inverters that have well-proven grid integration characteristics (i.e., the capability to produce energy with good power quality and control real power and voltage on the grid side).

Sea water pumping-up power plant system combined with nuclear power plant

International Nuclear Information System (INIS)

Ichiki, Tadaharu; Tanaka, Masayuki.

1991-01-01

It is difficult to find a site suitable to construction for a sea water pumping-up power plant at a place relatively near the electric power consumption area. Then, a nuclear power plant is set at the sea bottom or the land portion of a sea shore near the power consumption area. A cavity is excavated underground or at the bottom of the sea in the vicinity of the power plant to form a lower pond, and the bottom of the sea, as an upper pond and the lower pond are connected by a water pressure pipe and a water discharge pipe. A pump water turbine is disposed therebetween, to which electric power generator is connected. In addition, an ordinary or emergency cooling facility in the nuclear power plant is constituted such that sea water in the cavity is supplied by a sea water pump. Accordingly, the sea water pumping-up plant system in combination with the nuclear power plant is constituted with no injuring from salts to animals and plants on land in the suburbs of a large city. The cost for facilities for supplying power from a remote power plant to large city areas and power loss are decreased and stable electric power can be supplied. (N.H.)

Low-power laser therapy for carpal tunnel syndrome: effective optical power

Directory of Open Access Journals (Sweden)

Yan Chen

2016-01-01

Full Text Available Low-power laser therapy has been used for the non-surgical treatment of mild to moderate carpal tunnel syndrome, although its efficacy has been a long-standing controversy. The laser parameters in low-power laser therapy are closely related to the laser effect on human tissue. To evaluate the efficacy of low-power laser therapy, laser parameters should be accurately measured and controlled, which has been ignored in previous clinical trials. Here, we report the measurement of the effective optical power of low-power laser therapy for carpal tunnel syndrome. By monitoring the backside reflection and scattering laser power from human skin at the wrist, the effective laser power can be inferred. Using clinical measurements from 30 cases, we found that the effective laser power differed significantly among cases, with the measured laser reflection coefficient ranging from 1.8% to 54%. The reflection coefficient for 36.7% of these 30 cases was in the range of 10–20%, but for 16.7% of cases, it was higher than 40%. Consequently, monitoring the effective optical power during laser irradiation is necessary for the laser therapy of carpal tunnel syndrome.

Power reserve provision with wind farms. Grid integration of wind power

Energy Technology Data Exchange (ETDEWEB)

Gesino, Alejandro J.

2011-07-01

Wind power is, admittedly, different from other power technologies and integrating large amounts of it in the existing power systems is a challenge that requires innovative approaches to keep the sustainability of the power system operation. In the coming years its contribution to the system security will become mandatory as far as the trend goes towards more decentralized structures and an increase in complexity due to a higher number of market participants. This PhD addresses one of the fundamental ancillary services researching about a secure and flexible methodology for power reserve provision with wind farms. Based on the current needs and security standards of those highly developed European grid codes, a new model for power reserve provision with wind power is developed. This methodology, algorithms and variables are tested based on real scenarios from five German wind farm clusters. Finally, once the methodology for power reserve provision with wind power has been tested, real control capabilities from already installed wind farms in Germany and Portugal are analyzed. Their capabilities of following control commands as well as an error deviation analysis are also presented. (orig.)

Unified Power Flow Controller Placement to Improve Damping of Power Oscillations

OpenAIRE

M. Salehi; A. A. Motie Birjandi; F. Namdari

2015-01-01

Weak damping of low frequency oscillations is a frequent phenomenon in electrical power systems. These frequencies can be damped by power system stabilizers. Unified power flow controller (UPFC), as one of the most important FACTS devices, can be applied to increase the damping of power system oscillations and the more effect of this controller on increasing the damping of oscillations depends on its proper placement in power systems. In this paper, a technique based on controllability is pro...

Power distribution arrangement

DEFF Research Database (Denmark)

2010-01-01

An arrangement and a method for distributing power supplied by a power source to two or more of loads (e.g., electrical vehicular systems) is disclosed, where a representation of the power taken by a particular one of the loads from the source is measured. The measured representation of the amount...... of power taken from the source by the particular one of the loads is compared to a threshold to provide an overload signal in the event the representation exceeds the threshold. Control signals dependant on the occurring of the overload signal are provided such that the control signal decreases the output...... power of the power circuit in case the overload signal occurs...

Power grid complexity

Energy Technology Data Exchange (ETDEWEB)

Mei, Shengwei; Zhang, Xuemin [Tsinghua Univ., Beijing, BJ (China). Dept. of Electrical Engineering; Cao, Ming [Groningen Univ. (Netherlands). Faculty of Mathematics and Natural Sciences

2011-07-01

''Power Grid Complexity'' introduces the complex system theory known as self-organized criticality (SOC) theory and complex network theory, and their applications to power systems. It studies the network characteristics of power systems, such as their small-world properties, structural vulnerability, decomposition and coordination strategies, and simplification and equivalence methods. The book also establishes four blackout models based on SOC theory through which the SOC of power systems is studied at both the macroscopic and microscopic levels. Additionally, applications of complex system theory in power system planning and emergency management platforms are also discussed in depth. This book can serve as a useful reference for engineers and researchers working with power systems. (orig.)

76 FR 20624 - Oglethorpe Power Corporation: Proposed Biomass Power Plant

Science.gov (United States)

2011-04-13

... DEPARTMENT OF AGRICULTURE Rural Utilities Service Oglethorpe Power Corporation: Proposed Biomass Power Plant AGENCY: Rural Utilities Service, USDA. ACTION: Notice of Availability of a Draft... financial assistance to Oglethorpe Power Corporation (Oglethorpe) for the construction of a 100 megawatt (MW...

Powering biomedical devices

CERN Document Server

Romero, Edwar

2013-01-01

From exoskeletons to neural implants, biomedical devices are no less than life-changing. Compact and constant power sources are necessary to keep these devices running efficiently. Edwar Romero's Powering Biomedical Devices reviews the background, current technologies, and possible future developments of these power sources, examining not only the types of biomedical power sources available (macro, mini, MEMS, and nano), but also what they power (such as prostheses, insulin pumps, and muscular and neural stimulators), and how they work (covering batteries, biofluids, kinetic and ther

Intelligent Power Management of hybrid Wind/ Fuel Cell/ Energy Storage Power Generation System

OpenAIRE

A. Hajizadeh; F. Hassanzadeh

2013-01-01

This paper presents an intelligent power management strategy for hybrid wind/ fuel cell/ energy storage power generation system. The dynamic models of wind turbine, fuel cell and energy storage have been used for simulation of hybrid power system. In order to design power flow control strategy, a fuzzy logic control has been implemented to manage the power between power sources. The optimal operation of the hybrid power system is a main goal of designing power management strategy. The hybrid ...

Impact of integrating wind power in the Norwegian power system

International Nuclear Information System (INIS)

Tande, John Olav

2006-04-01

Wind power may in the future constitute a significant part of the Norwegian electricity supply. 20 TWh annual wind generation is a realistic goal for 2020 assuming wind farms on-land and offshore. The development of grid codes for wind farms is sound. It is recognising that large wind farms are basically power plants and may participate in securing efficient and stable power system operation. Modern wind farms may control the reactive power or voltage as any other power plant, and may also control active power or frequency as long as wind conditions permits. Grid code requirements must however be carefully assessed and possibly adjusted over time aiming for overall least cost solutions. Development of wind farms are today to some degree hindered by conservative assumptions being made on operation of wind farms in areas with limited power transfer capacity. By accepting temporary grid congestions, however, a large increase installed wind power is viable. For grid congestion that appears a few hours per year only, the cost of lost generation will be modest and may be economic over the alternatives of limiting wind farm capacities or increasing the grid transfer capacity. Wind generation impact on power system operation and adequacy will be overall positive. Combining wind and hydro provides for a more stable annual energy supply than hydro alone, and wind generation will generally be higher in the winter period than in the summer. Wind will replace the generation with the highest operating cost, and reduce the average Nord Pool spot market price. 20 TWh wind will reduce price with about 3 oere/kWh and CO 2 emissions by 12-14 million tons for the case of replacing coal, and about 6 million tons for replacing natural gas. Wind impact on need for balancing power is small, i.e. the extra balancing cost is about 0,8 oere per kWh wind, and about half if investment in new reserve capacity is not needed. In summary this report demonstrates options for large scale integration

Experience in connecting the power generating units of thermal power plants to automatic secondary frequency regulation within the united power system of Russia

International Nuclear Information System (INIS)

Zhukov, A. V.; Komarov, A. N.; Safronov, A. N.; Barsukov, I. V.

2009-01-01

The principles of central control of the power generating units of thermal power plants by automatic secondary frequency and active power overcurrent regulation systems, and the algorithms for interactions between automatic power control systems for the power production units in thermal power plants and centralized systems for automatic frequency and power regulation, are discussed. The order of switching the power generating units of thermal power plants over to control by a centralized system for automatic frequency and power regulation and by the Central Coordinating System for automatic frequency and power regulation is presented. The results of full-scale system tests of the control of power generating units of the Kirishskaya, Stavropol, and Perm GRES (State Regional Electric Power Plants) by the Central Coordinating System for automatic frequency and power regulation at the United Power System of Russia on September 23-25, 2008, are reported.

Green Certificates and Market Power on the Nordic Power Market

International Nuclear Information System (INIS)

Bergman, Lars; Amundsen, Eirik S

2007-06-01

In Sweden a market for Tradable Green Certificates (TGCs) was introduced in 2003. The purpose was to stimulate investments in electricity generation based on renewable energy sources without using direct governmental subsidies to renewable energy. More precisely the aim is to create a market where different types of renewable electricity can compete on equal terms, thus relieving governments and public agencies from being directly involved in power industry investment decisions. The purpose of this study is to elucidate under which circumstances, how, and to what extent market power in the TGC market can be used to affect the entire electricity market. There are basically two reasons for being concerned with market power in TGC markets. The first is the fact that the industry average cost curve for 'green' electricity tends to be upward sloping. This is because the cost of wind power, the main source of green electricity, depends on the location of the power plants, and that the availability of first rate sites that do not involve sizable investments in new transmission and network infrastructure, is limited. The situation is similar for environmentally friendly hydro power, and, to some extent, for other types of 'green' electricity. Thus, given the state of technology and an upper cost limit, there is a maximum amount of 'green' electricity that can be produced within a country. This means that some generators, by getting access to the suitable sites, will become dominating producers of 'green' electricity and thus may be able to exercise market power in the TGC market. The second reason for being concerned with market power in a TGC market is that, as a result of the percentage requirement, the withdrawal of a given number of TGCs from the market forces a much larger reduction of electricity consumption. Thus relatively modest exercise of market power in the TGC market may have a significant impact on the price of electricity and the allocation of resources in

Power facility plan and power supply plan of Japan in 1988

Energy Technology Data Exchange (ETDEWEB)

Yoshino, Shoji; Makino, Masao

1988-06-01

The power facility plan and the power supply plan for 1988 are described. The demand by non-industrial use will grow at an average of 3.8% for the 1986-97 period due to changes in the life style, construction and extension of buildings and increasing use of OA equipment although the power conservation is promoted. The industrial consumption will increase at only 1.2% a year due to the slowed growth and energy saving. As a result, the total demand will be 778,200 million kWh in 1997 with annual growth of 2.4%. The maximum demand will be 151,210 kW in 1997 with annual growth of 2.9%. The annual load rate will decrease to 56.9%, showing a continuously worsening utilization efficiency of power facilities. The development of 29 power units with total capacity of 2,760 MW is planned in 1988 for a stable power supply with a sufficient margin regarding maximum demand. The plan requires the investment of 3,700 billion yen, including the power transmission systems and substations. The power supply plan in 1988 is aimed at the effective operation of facilities and cost reduction by regional management under proper recognition of local characteristics of each power source, while maintaining a stable power supply with specified margins. (1 fig, 11 tabs)

Cooperation of nuclear, thermal and hydroelectric power plants in the power system

International Nuclear Information System (INIS)

1984-01-01

The conference heard 36 papers of which 23 were incorporated in INIS. The subjects discussed were: the development of power industry in Czechoslovakia, methods of statistical analysis of data regarding nuclear power plant operation, the incorporation of WWER nuclear power plants in the power supply system, the standardization of nuclear power plants, the service life of components, use of nuclear energy sources, performance of the reactor accident protection system, the use of nuclear power and heating plants in Hungary, risk analysis, optimization of nuclear power plants, accidents caused by leakage of the primary and secondary circuit. (J.P.)

Solar thermal power: the seamless solar link to the conventional power world

International Nuclear Information System (INIS)

Geyer, Michael; Quaschning, Volker

2000-01-01

This article focuses on solar thermal power generation and describes two solar thermal power concepts, namely, the parabolic trough or solar farm, and the solar central receiver or power tower. Details are given of grid-connected parabolic trough power plants in California and recent developments in collector design and absorber tubes, and the operation of power tower plants with different heat transfer media. Market issues are discussed, and solar thermal power projects under development, and application for support for solar thermal power projects under the Global Environment Facility's Operational Programme by Egypt, India, Iran, Mexico and Morocco are reported

Photonic-powered cable assembly

Science.gov (United States)

Sanderson, Stephen N.; Appel, Titus James; Wrye, IV, Walter C.

2013-01-22

A photonic-cable assembly includes a power source cable connector ("PSCC") coupled to a power receive cable connector ("PRCC") via a fiber cable. The PSCC electrically connects to a first electronic device and houses a photonic power source and an optical data transmitter. The fiber cable includes an optical transmit data path coupled to the optical data transmitter, an optical power path coupled to the photonic power source, and an optical feedback path coupled to provide feedback control to the photonic power source. The PRCC electrically connects to a second electronic device and houses an optical data receiver coupled to the optical transmit data path, a feedback controller coupled to the optical feedback path to control the photonic power source, and a photonic power converter coupled to the optical power path to convert photonic energy received over the optical power path to electrical energy to power components of the PRCC.

Women, Power, and Libraries.

Science.gov (United States)

Schuman, Patricia Glass

1984-01-01

Discusses the concept of power in the context of women and the library profession, citing views of power by Max Weber, John Kenneth Galbraith, Letty Cottin Pogrebin, and Rosabeth Moss Kantor. Male power and female submission, defining power, organizing for power, and sharing power are highlighted. A 12-item bibliography is included. (EJS)

A study on electric power management for power producer-suppliers utilizing output of megawatt-solar power plants

Directory of Open Access Journals (Sweden)

Hirotaka Takano

2016-01-01

Full Text Available The growth in penetration of photovoltaic generation units (PVs has brought new power management ideas, which achieve more profitable operation, to Power Producer-Suppliers (PPSs. The expected profit for the PPSs will improve if they appropriately operate their controllable generators and sell the generated electricity to contracted customers and Power Exchanges together with the output of Megawatt-Solar Power Plants (MSPPs. Moreover, we can expect that the profitable cooperation between the PPSs and the MSPPs decreases difficulties in the supply-demand balancing operation for the main power grids. However, it is necessary that the PPSs treat the uncertainty in output prediction of PVs carefully. This is because there is a risk for them to pay a heavy imbalance penalty. This paper presents a problem framework and its solution to make the optimal power management plan for the PPSs in consideration with the electricity procurement from the MSPPs. The validity of the authors’ proposal is verified through numerical simulations and discussions of their results.

Robust Power Control of Microgrid based on Hybrid Renewable Power Generation Systems

Directory of Open Access Journals (Sweden)

A. Hajizadeh

2013-03-01

Full Text Available This paper presents modeling and control of a hybrid distributed energy sources including photovoltaic (PV, fuel cell (FC and battery energy storage (BES in a microgrid which provides both real and reactive power to support an unbalanced utility grid. The overall configuration of the microgrid including dynamic models for the PV, FC, BES and its power electronic interfacing are briefly described. Then controller design methodologies for the power conditioning units to control the power flow from the hybrid power plant to the unbalanced utility grid are presented. In order to distribute the power between power sources, the neuro-fuzzy power controller has been developed. Simulation results are presented to demonstrate the effectiveness and capability of proposed control strategy.

Tasks of a power engineer in future thermal power plants

International Nuclear Information System (INIS)

Freymeyer, P.; Scherschmidt, F.

1982-01-01

Today already the power plants provide plenty of tasks and problems to the electrical engineer in the fields of power and conductive engineering. A completely new orientation of power engineering leads to larger, more complex system and even to systems unknown so far. In conductive engineering entirely new solutions have come in view. There are a lot of interesting topics for the electrical engineer in the rearrangement and advance into virgin territory of thermal power plants. (orig.) [de

Dynamic impedance compensation for wireless power transfer using conjugate power

OpenAIRE

Suqi Liu; Jianping Tan; Xue Wen

2018-01-01

Wireless power transfer (WPT) via coupled magnetic resonances has been in development for over a decade. However, the frequency splitting phenomenon occurs in the over-coupled region. Thus, the output power of the two-coil system achieves the maximum output power at the two splitting angular frequencies, and not at the natural resonant angular frequency. According to the maximum power transfer theorem, the impedance compensation method was adopted in many WPT projects. However, it remains a c...

Different Frequencies between Power and Efficiency in Wireless Power Transfer

OpenAIRE

Muhammad Afnan, Habibi; Hodaka, Ichijo

2017-01-01

Wireless Power Transfer (WPT) has been recognized as a common power transfer method because it transfers electric power without any cable from source to the load. One of the physical principle of WPT is the law of electromagnetic induction, and the WPT system is driven by alternative current power source under specific frequency. The frequency that provides maximum gain between voltages or currents is called resonance frequency. On the other hand, some studies about WPT said that resonance fr...

Pulsed power

International Nuclear Information System (INIS)

Anon.

1977-01-01

The key element of our pulsed power program is concentration of power in time and space by suppression of breakdown in dielectrics and in vacuum. Magnetically insulated vacuum transmission lines and magnetic suppression of insulator flashover have continued as the main reserch directions. Vacuum insulated line studies at Physics International have been expanded and a test bed at Sandia, called MITE (Magnetically Insulated Transmission Experiment), is under development. The choice for the baseline EBFA design will depend on the outcome of these studies and should be made in July 1977. The slow and intermediate speed pulsed power approaches to EBFA will be based on Proto I and Proto II results and several of the projected EBFA subsystems are presently being tested in Proto II. A further stage of power concentration, within the vacuum diode itself, would considerably ease the burden on dielectrics; methods of power multiplication involving magnetically imploded plasmas are being considered and tests have begun using the Ripple III apparatus

Power without Glory

DEFF Research Database (Denmark)

Jørgensen, Kenneth Mølbjerg

This book is about power and language in organizations. Its purpose is, more specifically, to develop and apply a method for exploring power in organizations where organizations are conceptualized by drawing on Wittgenstein’s concept of language games. The method is genealogy and is closely linked...... to Foucault’s conception of power. The book is written with one main purpose—to highlight some aspects of Foucault’s conception of power that, in my opinion, are not sufficiently explored in extant organization studies: Genealogy and the practices of power....

Power system relaying

CERN Document Server

Horowitz, Stanley H; Niemira, James K

2013-01-01

The previous three editions of Power System Relaying offer comprehensive and accessible coverage of the theory and fundamentals of relaying and have been widely adopted on university and industry courses worldwide. With the third edition, the authors have added new and detailed descriptions of power system phenomena such as stability, system-wide protection concepts and discussion of historic outages. Power System Relaying, 4th Edition continues its role as an outstanding textbook on power system protection for senior and graduate students in the field of electric power engineering and a refer

Simulation of the energy - environment economic system power generation costs in power-stations

International Nuclear Information System (INIS)

Weible, H.

1978-09-01

The costs of power generation are an important point in the electricity industry. The present report tries to supply a model representation for these problems. The costs of power generation for base load, average and peak load power stations are examined on the basis of fossil energy sources, nuclear power and water power. The methods of calculation where dynamic investment calculation processes are used, are given in the shape of formulae. From the point of view of long term prediction, power generation cost sensitivity studies are added to the technical, economic and energy-political uncertainties. The sensitivity of models for calculations is examined by deterministic and stochastic processes. In the base load and average region, power generation based on nuclear power and water power is economically more favourable than that from fossilfired power stations. Even including subsidies, this cost advantage is not in doubt. In the peak load region, pumped storage power stations are more economic than fossilfired power stations. (orig.) [de

Radiation effects on power cables for nuclear power plants

International Nuclear Information System (INIS)

Arora, R.; Munshi, P.; Badshah, M.G.Q.

1988-01-01

A large number of power and control cables, insulated with organic/polymeric materials, are installed quite near the reactor in nuclear power plants. The reliability of electrical equipment, receiving power through these cables, is critically important for the design and safety of the power stations. The radiation intensity inside the containment varies significantly from one location to another. The extent of material degradation is associated with the local radiation intensity. The cables used in the nuclear environment require several unique properties, the most obvious of these being radiation resistance, fire resistance, and the ability to withstand the loss-of-coolant accident in a nuclear power plant as specified in Institute of Electrical and Electronics Engineers (IEEE) Standard 383. In this study, four specific electrical power cable samples insulated with polyethylene, polyvinyl chloride, ethylene propylene rubber, and silicone rubber were chosen to investigate the effect of radiation in reactor environments on the electrical properties of the samples. Voltage breakdown tests and dielectric loss factor (tan δ) and conductor resistance measurements were carried out on each sample before and after irradiating them to near lifetime doses at ambient temperatures in atmospheric conditions

Load following operation of nuclear power plants for meeting power system requirements

International Nuclear Information System (INIS)

Isoda, Hachiro

1987-01-01

This paper describes a calculating program on the availability factors of nuclear, thermal and pumed storage hydro power stations and some calculated results for typical three load factors, 55 %, 60 % and 71 %, are provided when the share of the nuclea power station in the generation facilities is increased. The load following requirement of the nuclear power station is also provided. Load following requirement: If there is a 10 % pumped storage hydro power station, the nuclear power station enables to be operated with its rated output up to 30 % - 35 % of its share. Its daily load following operation for 40 % and 50 % nuclear power station needs every weekend and every day respectively. Availability factor: The availability factor of the nuclear power station manages to get 80 % (maximum availability factor of the nuclear power station in this study) up to 30 % share of it with 10 % pumpued storage hydro power station. When the nuclear power station shares 40 % and 50 %, its availability factor decreases down 1 % and 5 % respectively. (author)

Power Quality Improvements in Wind Diesel Power Generation System

Directory of Open Access Journals (Sweden)

Omar Feddaoui

2015-08-01

Full Text Available Generation of electricity using diesel is costly for small remote isolated communities. At remote location electricity generation from renewable energy such as wind can help reduce the overall operating costs by reducing the fuel costs. However, the penetration of wind power into small diesel-based grids is limited because of its effect on power quality and reliability. This paper focuses on the combination of Wind Turbine and Diesel Generator systems for sustained power generation, to improve the power quality of wind generation system. The performances of the optimal control structure are assessed and discussed by means of a set of simulations.

Characterization and design of a low-power wireless power delivery system

Science.gov (United States)

Falkenstein, Erez Avigdor

There is an increased demand for wireless sensors for data gathering and transmission where running wires to power a device or changing/charging batteries is difficult. Often the data is gathered at locations that are difficult to access, that need to be covert, and/or where the sensors cannot be easily maintained. Some examples are implanted sensors for medical diagnostics and therapy, structural monitoring sensors, sensors inside hazardous manufacturing or other hazardous environments, etc. For any low power sensor that operates at a low duty cycle, and in an environment with low levels of light or vibration, RF wireless powering offers the potential for maintenance-free operation. The thesis focuses on a design methodology for low-power non-directional far-field wireless powering. The power receiver consists of one or more antennae which receive plane waves transmitted by the powering source, and deliver the RF power to a rectifying element. The resulting DC power is optimally transferred to the electronic application via a power management circuit. The powering is independent of the electronic application which can include wireless transmission of sensor data. The design and implementation of an integrated rectifier-antenna at low incident power densities (from 25--200 muW/cm2) is presented. Nonlinear source-pull measurements and harmonic balance simulations are used for finding the optimal rectifying device RF and DC impedances for efficient rectification. Experimental results show that an antenna design with a specific complex impedance reaches the highest rectification efficiency. Several examples of the design methodology will be shown. In specific, characterization of a rectifying patch antenna at frequency of 2.45GHz will be detailed, with an optimal RF impedance of 137+j149O and an optimal DC load of 365O resulting in RF to DC conversion efficiency of 63% for the rectifier alone and 56% for the total rectifying antenna.