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  • 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.
21

DC capacitor voltage balancing in multi-level converters

Espah Boroojeni, Mehrdad 19 January 2012 (has links)
Multi-level converters that provide more than two levels of voltage to achieve an output waveform closer to sinusoidal waveform with less distortion are very attractive to power applications. This thesis investigates several multi-level converter topologies and different modulation strategies such as pulse-width modulation and space vector modulation. Attention is paid in particular to SVM strategy. Although SVM strategy is applicable for N-level converter, this thesis only focuses on five-level and three-level diode clamped converter (DCC). Despite their appealing harmonic spectrum and low losses, multi-level converters are known to suffer from inherent voltage imbalance on their dc side. The thesis presents a method in order to balance the dc side capacitor voltages for an N-level converter. The presented balancing method is based on minimizing a cost function which is related to voltage divergence of the dc capacitors. This method is used for a three-level SVM to overcome the voltage drifting problem.
22

DC capacitor voltage balancing in multi-level converters

Espah Boroojeni, Mehrdad 19 January 2012 (has links)
Multi-level converters that provide more than two levels of voltage to achieve an output waveform closer to sinusoidal waveform with less distortion are very attractive to power applications. This thesis investigates several multi-level converter topologies and different modulation strategies such as pulse-width modulation and space vector modulation. Attention is paid in particular to SVM strategy. Although SVM strategy is applicable for N-level converter, this thesis only focuses on five-level and three-level diode clamped converter (DCC). Despite their appealing harmonic spectrum and low losses, multi-level converters are known to suffer from inherent voltage imbalance on their dc side. The thesis presents a method in order to balance the dc side capacitor voltages for an N-level converter. The presented balancing method is based on minimizing a cost function which is related to voltage divergence of the dc capacitors. This method is used for a three-level SVM to overcome the voltage drifting problem.
23

Sequence stratigraphic control on carbonate cementation in distal shallow marine sandstones : Upper Cretaceous Book Cliffs, Utah, USA

Machent, Philip Geoffrey January 2003 (has links)
No description available.
24

Examining the strategic impact of using enterprise systems in manufacturing businesses

Ullmann, Kay Dirk January 2001 (has links)
No description available.
25

Erfolgsfaktoren im Network-Management Aufbau und Gestaltung hierarchieloser Netzwerke

Schmiech, Chris January 2007 (has links)
Zugl.: Kassel, Univ., Diss., 2007
26

Multi-Level-Marketing Identität und Ideologie im Network-Marketing

Gross, Claudia January 2007 (has links)
Zugl.: Mannheim, Univ. Diss., 2007
27

Decadal mass balance of the Antarctic ice sheet from satellite radar altimetry and its contribution

Li, Yonghong. January 2006 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 29, 2009) Vita. Includes bibliographical references.
28

Multi-Level-Marketing : Identität und Ideologie im Network-Marketing

Gross, Claudia January 2008 (has links)
Zugl.: Mannheim, Univ., Diss., 2007
29

Slope of sea level along U.S. coasts,

Sturges, Wilton, January 1966 (has links)
Thesis (Ph. D.)--Johns Hopkins University, 1966. / Bibliography: leaves 66-70.
30

Erfolgsfaktoren im Network Management : Aufbau und Gestaltung hierarchieloser Netzwerke /

Schmiech, Chris. January 2008 (has links)
Zugl.: Kassel, Universiẗat, Diss., 2007.

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