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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.
191

Control and Interfacing of Three Phase Grid Connected Photovoltaic Systems

Khalifa, Ahmed Said January 2010 (has links)
Solar power is considered a very promising source for electric power generation. The abundance of sunlight over a large area of the earth surface gives rise to several applications of photovoltaic systems. Electricity can be generated from sunlight either directly by employing the photovoltaic effect, or by using energy from the sun to heat up a working fluid that can be used to power up electricity generators. These two technologies are widely used today to provide power to either stand-alone loads or for connection to the power system grid. Maximum power point tracking (MPPT) is a very important consideration that is taken into account when building a new photovoltaic power system. This is needed in order to extract maximum power output from a PV array under varying atmospheric conditions to maximize the return on initial investments. Several techniques have been used to tackle this problem including perturb and observe (P&O), incremental conductance (IncCond) and fuzzy logic based algorithms. Judging between these techniques is based on their speed of locating the maximum power point (MPP) of a PV array under given atmospheric conditions, besides the cost and complexity of implementing them. The P&O and IncCond algorithms have a low implementation complexity but their tracking speed is slow. Fuzzy logic techniques are faster but suffer from high implementation complexity. One of the goals of this thesis is to present an MPPT algorithm implementation that is based on the fractional open circuit voltage method. This technique is easy to implement and offers a fast tracking speed for the MPP of a PV array. It provides an approximation within 4-5% of the maximum power point, which is a tradeoff between the speed and accuracy of operation around the MPP. It offers a speed advantage in grid connected PV systems. The P&O algorithm, which is very common, is difficult to implement under these conditions due to its poor response time. There is also a need for developing control techniques for three phase grid connected PV systems including a method for DC link voltage control that can stabilize the voltage at the inverter input. This area of research is currently growing with the increase in number of PV installations backed up by government incentives in several countries. In addition to the previously mentioned points, this work is intended to be used in further research to replace the representation of PV arrays as a simple DC source when included in power system studies. That is a basic assumption and does not take into consideration the various dynamics caused by changing solar irradiation and surface temperature of the array.
192

Optical phonon modes of PbSe nanoparticles

Carreto, Francisco Javier, January 2007 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
193

Synthesis and optical properties of four oligothiophene-ruthenium complexes and synthesis of a bidentate ligand for C-F bond activation /

Bair, Joseph Spencer, January 2006 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Chemistry and Biochemistry, 2006. / Includes bibliographical references.
194

A solar concentrating photovoltaic/thermal collector /

Coventry, Joseph Sydney. January 2004 (has links)
Thesis (Ph.D.)--Australian National University, 2004.
195

Infrared furnace emitter diffusion for solar cells /

Voyer, Catherine, January 1900 (has links)
Thesis (M. App. Sc.)--Carleton University, 2003. / Includes bibliographical references (p. 112-118). Also available in electronic format on the Internet.
196

Bandstructure engineering of indium arsenide quantum dots in gallium arsenide antimonide barriers for photovoltaic applications

Boyle, Jonathan. January 2008 (has links)
Thesis (M.M.S.E.)--University of Delaware, 2008. / Principal faculty advisor: Valeria Gabriela Stoleru, Dept. of Materials Science & Engineering. Includes bibliographical references.
197

Modeling solutions and simulations for advanced III-V photovoltaics based on nanostructures /

Aguinaldo, Ryan. January 2008 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2008. / Typescript. Includes bibliographical references (p. 151-153).
198

Triple junction amorphous silicon based flexible photovoltaic submodules on polyimide substrates /

Vijh, Aarohi. January 2005 (has links)
Dissertation (Ph.D.)--University of Toledo, 2005. / Typescript. "As partial fulfillment of the requirements for the Doctor of Philosophy Degree in Engineering."
199

Rectifying characteristics, photovoltaic effect and magnetoresistance in heterojunctions composed of manganite and titanate

Luo, Zhi, January 2008 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references. Also available in print.
200

Characterisation of organic materials for photovoltaic devices /

Lewis, Andrew J. January 2006 (has links)
Thesis (Ph.D.) - University of St Andrews, October 2006.

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