131 research outputs found
Is there any future for the power system network ? (white book)
Il s'agit d'un livre blanc sur l'avenir du réseau d'énergie électrique : devra-t-il encore exister demain ? Quels sont les avantages et les inconvénients soit du système actuel soit des micro-réseaux individuels
Which energy policy in Belgium for the next 30 years ?
L’évolution vers les énergies renouvelables (éoliennes et panneaux photovoltaïques) paraît incontournable. La cogénération (électricité et chaleur) aussi. Sans doute faut-il faire encore des progrès dans le stockage de l’énergie et, peut-être, dans l’utilisation de l’hydrogène. Hélas la variabilité du climat ne génère pas une production constante d’énergie. Notre proposons dès lors une solution basée sur une solidarité européenne (au sens large) et une souplesse d’utilisation du réseau d’énergie électrique. Tout en prônant un changement radical de paradigme : notre consommation doit s’adapter à la production et non l’inverse
Full-scale tests of torsional damper and detuner (TDD) antigalloping device
peer reviewedA new antigalloping device for overhead lines with bundle conductors was introduced ten years ago, after laboratory tests and observations on actual 400-kV lines. A systematic fullscale test was performed in Kazakhstan in order to better evaluate torsional damper and detuner (TDD) efficiency. This report details the test station and the results obtained over a several month period of testing and measurement. The tests were carried out thanks to the mutual efforts of the ESSP and the Kazakh Power Research Institute (KazNIIE) at the field tests stand located in Chokpar.INTAS 51-373
Industrial adoption of solar air conditioning : measurement problems, solutions and marketing implications
Short-circuit mechanical effects on outdoor HV substations with wide bundling.
peer reviewedThis paper presents results of a research project investigating the mechanical effects of short-circuit currents in high-voltage substations with conductor bundles. The experimental part was performed on two set-ups, called "100 kV arrangement" and "400 kV arrangement". Those two set-ups differed in the height of the crossarm, the phase-to-phase distance and the conductor sag. Additional parameters which were varied in the course of the experiments included the level and duration of the short-circuit current, the type and number of the spacers used and the bundle spacing. Various forces in the flexible busbar and the supporting structure were recorded during the tests and the stiffness as well as the eigenfrequency of the portals used for supporting the conductors were determined.
The test results were evaluated with respect to the maxima of the pinch force, the tensile force and the drop force. They are presented and compared with existing assumptions and calculation methods. The results of this project shall enable IEC standardization committees and CIGRE working groups to carry on with their intended studies and establish a comprehensive method of calculating the mechanical effects in substations with bundle conductors
The mechanical effects of short-circuit currents in open air substations.
SHort-circuit mechanical effects in substation is investigated by tests and simulations. Simplified equations are deduced to prepare standardisation of a procedure forthe design of substation against short-circuit mechanicle effects
Wake-Induced Vibration in Power Transmission Line. Parametric study
peer reviewedThe paper discusses some aspects of modeling the wake-induced vibrations of the bundle conductors in transmission lines.
The wake coupling between subconductors is modeled with the modified Simpson’s approach. In order to apply this model to the analysis of power transmission line (PTL), a modal representation of a span could be used. In present paper we study how application of Dynamic Reduction (Component Mode) technique may improve such analysis under finite-element approach. The present paper, to extent of authors’ knowledge, is the first where Component Mode method application is discussed to study the subspan oscillation.
Finally, bundled conductors’ susceptibility to wake-induced vibrations is illustrated on an exemplary twin-bundle, three-subspan model. Effects of bundle parameters (initial subconductor spacing, frequency ratio, subconductor mass), and the means to account them when applying the component mode method are discussed
Electrification Rurale. Vers une technique innovatrice pour l'Afrique.
peer reviewedIn many developing countries , there are a lot of high voltage lines which cross many regions to supply electricity to the main towns or connect to networks the distanced electric substations .
These lines, used for supplying electricity to big towns, cross a lot of villages whose people broadly poor hope to be supplied with electricity without a suitable solution.
However it seems very deplorable that the power conducted by these lines doesn’t profit to surrounding population.
Unfortunately , for these villages , the use of classical substations is too expensive to the power distributors because of high cost of investment and production for these potential scattered consumers with the low demand of electricity.
This paper presents the original solution settled in 2002 in one of the village located in Congo Brazzaville and continue to operate correctly in 2006. It is a new power transformer, based on the technique of SF6 measuring transformer, which is connected on one phase of the high voltage line 220kV and which produces the low voltage 230 V directly useful by the rural population.
This prototype sample for the rural electrification has been designed to deliver a power of 50kVA. A cheap and robust system ! It requires a large popularization, mainly in sub saharian Africa that has got many such opportunities. Outside the role of bulk power transmission, the high voltage line is now also able to distribute a part of it.On trouve dans les pays en développement de nombreux cas de lignes à haute tension qui traversent des régions entières pour alimenter les principales villes ou relient au réseau des centrales électriques éloignées.
Ces lignes prévues pour l’alimentation en électricité des grandes agglomérations traversent sur leur passage de nombreux petits villages dispersés et dont les habitants souvent pauvres, espèrent en vain d’être alimentés en électricité.
Il paraît cependant très regrettable que le flux de puissance que ces lignes transportent ne puisse être partiellement déployé au profit des ces populations riveraines impatientes.
Malheureusement pour ces villages, le recours à des postes classiques HT / MT et MT / BT s’annonce trop coûteux pour les distributeurs d’énergie à cause des investissements et des coûts de production élevés pour un marché où les consommateurs sont dispersés sur des distances considérables et pour une demande globale énergétique faible.
Cet article présente une solution originale installée en 2002 dans un village du Congo Brazzaville et qui continue à fonctionner à merveille. Il s’agit d’un nouveau type de transformateur monophasé, qui est relié sur un conducteur de phase de la ligne à HT 220kV et qui délivre spectaculairement de la basse tension 230 volts directement utilisable par les populations rurales.
Ce prototype conçu pour l’électrification rurale, a été dimensionné pour une puissance de 50kVA , basé sur la technologie des transformateurs de mesure isolé au SF6. Un appareil bon marché et dont la fiabilité n’est plus à démontrer ; il mérite une diffusion à grande échelle et surtout sa vulgarisation en Afrique subsaharienne qui possède de nombreux sites potentiels. Au-delà de sa mission première de transport d’énergie, la ligne à haute tension peut maintenant jouer également un rôle de distribution.Electrification rural
Management of Electric and Hybrid vehicles
peer reviewedThe battery management system (BMS) is an important feature for electric (EVs) and hybrid (HVs) vehicles. The BMS has close connections with the vehicle control and command and gives access to real time power available and remaining autonomy. Such information is dramatic and comprises major inputs of the hybrid vehicle strategy on the road. The BMS is obviously related to battery modeling.
Electrochemical modeling would be based on the qualification of the intrinsic chemical reactions and would help to define the parameters of the battery. Generally it is hopeless to use this model in such applications, due to all its complexitie
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