• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 266
  • 227
  • 34
  • 18
  • 15
  • 7
  • 6
  • 6
  • 6
  • 6
  • 6
  • 5
  • 5
  • 3
  • 3
  • Tagged with
  • 684
  • 684
  • 488
  • 262
  • 261
  • 233
  • 171
  • 115
  • 108
  • 87
  • 76
  • 67
  • 66
  • 65
  • 53
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

La répartition optimale de la puissance réactive pour le contrôle des tensions de barre d'un réseau électrique par simplex LP /

Diarra, Adama D., January 1984 (has links)
Mémoire (M. Sc. A.)-- Université du Québec à Chicoutimi, 1984. / bibliographie: f. 102-104. Document électronique également accessible en format PDF. CaQCU
262

Reduced order power system models for transient stability studies /

Anderson, Sharon Lee. January 1993 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 78-79). Also available via the Internet.
263

Influence de la variation de la température ambiante sur les vibrations induites par effet de couronne /

Hamel, Myriam. January 1991 (has links)
Mémoire (M.Sc.A.)-- Université du Québec à Chicoutimi, 1991. / Bibliogr.: f. 86-91. Document électronique également accessible en format PDF. CaQCU
264

Contribution to study of visible discharge initiation and development on the ice surface = Contribution à l'étude de l'apparition et du développement des décharges visibles à la surface de la glace /

Brettschneider, Stephan, January 2000 (has links)
Thèse (D.Eng.)--Université du Québec à Chicoutimi, 2000. / Document électronique également accessible en format PDF. CaQCU
265

System reliability estimation and component replacement analysis for electricity transmission and distribution systems

Espiritu Nolasco, Jose. January 2007 (has links)
Thesis (Ph. D.)--Rutgers University, 2007. / "Graduate Program in Industrial and Systems Engineering." Includes bibliographical references (p. 181-186).
266

Distributed series reactance a new approach to realize grid power flow control /

Johal, Harjeet. January 2008 (has links)
Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Divan, Deepakraj M.; Committee Member: Begovic, Miroslav M.; Committee Member: Brown, Marilyn; Committee Member: Harley, Ronald G.; Committee Member: Wolf, Wayne H. Part of the SMARTech Electronic Thesis and Dissertation Collection.
267

Monopoly bidding strategy under the Ontario MPMA and system reliability /

He, Aiming. January 1900 (has links)
Thesis (Ph.D.) - Carleton University, 2007. / Includes bibliographical references (p. 180-182). Also available in electronic format on the Internet.
268

Technical consideration and impact of converting overhead power lines to underground power cables

Al-Khalidi, Hassan. January 2009 (has links)
Thesis (Ph.D.)--Victoria University (Melbourne, Vic.), 2009.
269

Αντικεραυνική προστασία εναέριων γραμμών διανομής : προσομοίωση γραμμής διανομής με στοιχεία ελληνικού δικτύου

Μαρούλης, Στυλιανός 20 October 2010 (has links)
Η εργασία αυτή παρουσιάζει τους σημαντικότερους μηχανισμούς με τους οποίους οι υπερτάσεις προκύπτουν από κεραυνό στα εναέρια δίκτυα διανομής ισχύος μέσης και χαμηλής τάσης, όπως επίσης και τυπικές κυματομορφές υπερτάσεων. Η αποτελεσματικότητα των πιο σημαντικών μεθόδων για να μετριάσουμε τέτοιες υπερτάσεις σε δίκτυα μέσης και χαμηλής τάσης συζητούνται επίσης. Αρχικά γίνεται αναφορά στο φαινόμενο του κεραυνού, στο πως δημιουργείται ο κεραυνός καθώς και στα προβλήματα που μπορεί να δημιουργήσει. Στη συνέχεια γίνεται μια σύντομη αναφορά στον τρόπο που είναι δομημένο το εναέριο δίκτυο διανομής και στον τρόπο λειτουργίας του, πριν ξεκινήσει η ανάλυση της αντικεραυνικής συμπεριφοράς του και η μελέτη τρόπων για τη βελτίωση αυτής. Τέλος, παρουσιάζεται η προσομοίωση ενός ελληνικού δικτύου εναέριας διανομής ηλεκτρικής ενέργειας με τη χρήση του προγράμματος ΑΤΡ - ΕΜΤΡ και μελετάται η συμπεριφορά του μετά την πτώση κεραυνού σε αυτή εξάγοντας συμπεράσματα και προτείνοντας λύσεις για τη βελτίωση της. / This work presents the major mechanisms by which the overvoltages are stemmed from lightning in both medium and low voltage overhead power distribution networks, as well as typical surge waveforms. The effectiveness of the main protective measures that can be utilized to improve the line lightning performance are also discussed. Initially what is briefly described is the lightning phenomenon, the ways it is created and the problems it can cause as well. Afterwards the way that the overhead distribution power network is structured is presented as well as the way it works, ending with the complete method of its lightning protection in theoretical basis and the ways this can be improved. Finally, we performed the simulation of a greek overhead power distribution network using the ATP - EMTP software, we studied its lightning performance by making conclusions and proposing ways it can be improved.
270

Transient modelling of induction motors in a petrochemical plant using Matlab

Claassens, Andries Johannes 03 1900 (has links)
Thesis (MScIng)--University of Stellenbosch, 2008. / ENGLISH ABSTRACT: The behaviour of induction motors at a petrochemical plant under transient conditions was investigated with the view to improve plant immunity to voltage fluctuations. The benefits of using a phase-variable induction motor model rather than the simpler d-q models usually employed are investigated. A simplified model of the plant electrical distribution system was derived. Phase variable and d-q induction motor models were implemented as well as a synchronous generator model. Practical considerations precluded the use of commercial software for the simulation of transient conditions and a basic simulation program was developed using Matlab to evaluate the behaviour of the dynamic machine models and distribution system. It was established that the configuration of the installed re-acceleration system can be optimised to reduce the possibility of plant outages as a result of voltage fluctuations. It was found that the use of more detailed induction machine models provide valuable insight into system behaviour and is justified if accurate motor parameters are available or can be estimated. The simplified plant model yielded useful results and enabled the identification of incorrect system data. The investigation showed that Matlab is suitable for the rapid development of a basic transient simulation program that can be used to study the behaviour of different interconnected dynamic machine models. / AFRIKAANSE OPSOMMING: Die gedrag van induksiemotors in 'n petrochemiese aanleg onder oorgangstoestande is ondersoek ten einde die immuniteit van die aanleg vir spanningsfluktuasies te verbeter. Die voordele van die gebruik van 'n fase-veranderlike induksiemotor model eerder as die eenvoudiger d-q modelle wat normaalweg gebruik word is ondersoek. 'n Vereenvoudigde model van die aanleg se elektriese distribusiestelsel is afgelei. Faseveranderlike en d-q induksiemotor modelle is geimplementeer sowel as 'n sinkroongenerator model. Praktiese oorwegings het die gebruik van kommersiële programmatuur vir die simulasie van oorgangstoestande verhoed en 'n basiese program is in Matlab ontwikkel om die gedrag dinamiese masjienmodelle en die distribusiestelsel te evalueer. Daar is vasgestel dat die konfigurasie van die geinstalleerde herversnellerstelsel geoptimeer kan word om die moontlikheid van aanleg onderbrekings as gevolg van spanningsfluktuasies te verminder. Daar is gevind dat die gebruik van meer gedetaileerde induksiemasjien modelle waardevolle insig in die gedrag van die stelsel lewer en geregverdig is indien akkurate motorparameters beskikbaar is of afgeskat kan word. Die vereenvoudigde model van die aanleg het bruikbare resultate gelewer en die het die identifikasie van foutiewe stelseldata moontlik gemaak. Die ondersoek het getoon dat Matlab geskik is vir die snelle ontwikkeling van 'n basiese oorgangsimulasie program wat gebruik kan word om die gedrag van verskillende gekoppelde dinamiese masjienemodelle te bestudeer.

Page generated in 0.0888 seconds