Sökning: "Conduction losses"

Visar resultat 16 - 20 av 31 avhandlingar innehållade orden Conduction losses.

  1. 16. In the confines of Cu(In,Ga)Se2 thin film solar cells with rear surface passivating oxide layers

    Författare :Dorothea Ledinek; Marika Edoff; Charlotte Platzer Björkman; Jan Keller; Christian Kaufmann; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Alkali; Alumina; Back contact; CIGS; CIGSe; Hafnia; Passivation; Rear contact; Sodium fluoride; Ultra-thin; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

    Sammanfattning : The material supply to build renewable energy conversion systems needs to be considered from both a cost and an energy security perspective. For Cu(In,Ga)Se2 (CIGS) thin film solar cells the use of indium in the absorber layer is most problematic. LÄS MER

  3. 17. Alternative Redox Couples for Dye-Sensitized Solar Cells

    Författare :Sandra Feldt; Anders Hagfeldt; Gerrit Boschloo; Petra Cameron; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; redox mediator; triphenylamine; cobalt; ferrocene; titanium dioxide; regeneration; recombination; Physical Chemistry; Fysikalisk kemi;

    Sammanfattning : Dye-sensitized solar cells (DSCs) convert sunlight to electricity at a low cost. In the DSC, a dye anchored to a mesoporous TiO2 semiconductor is responsible for capturing the sunlight. LÄS MER

  4. 18. Main Circuits, Submodules, and Auxiliary Power Concepts for Converters in HVDC Grids

    Författare :Stefanie Heinig; Hans-Peter Nee; Staffan Norrga; Kalle Ilves; Rainer Marquardt; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ac–dc power conversion; energy storage; fault tolerance; HVDC converters; HVDC grid; isolated power supply; modular multilevel converter MMC ; power system faults; silicon carbide; submodules; voltage source converter VSC ; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : In order to enable the massive introduction of renewable energies the need for high-voltage direct current (HVDC) grids is anticipated. Large, globally interconnected HVDC networks will likely be the most cost-efficient means to balance electricity demand and available generation. LÄS MER

  5. 19. Electrical Insulating Properties of Poly(Ethylene-co-Butyl Acrylate) Filled with Alumina Nanoparticles

    Författare :Nadejda Jäverberg; Hans Edin; John Fothergill; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nanocomposites; poly ethylene-co-butyl acrylate ; EBA; alumina; dielectric permittivity; absorbed water; humidity; temperature; dielectric spectroscopy; breakdown strength; pre-breakdown current;

    Sammanfattning : In this work the electrical insulating properties of the nanocomposite materials based on poly(ethylene-co-butyl acrylate) filled with alumina nanoparticles are studied. The dielectric properties chosen for the evaluation are the dielectric permittivity and loss as well as the breakdown strength and the pre-breakdown currents. LÄS MER

  7. 20. Diamond Devices Based on Valley Polarization

    Författare :Nattakarn Suntornwipat; Jan Isberg; Markus Gabrysch; Saman Majdi; Hitoshi Umezawa; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CVD diamond; valleytronics; Negative Differential Mobility; NDM; electron polarization; Time-of-Flight; magnetotransport; carrier transport; drift velocity; valley-transistor; Transferred-Electron Oscillator; TEO; TED; Gunn diode;

    Sammanfattning : Diamond is a wide bandgap semiconductor with extreme properties such as high thermal conductivity, high breakdown field, high carrier mobilities and chemical inertness. These properties together with the possibility to synthesize high purity Single-Crystalline (SC) diamond by Chemical Vapor Deposition (CVD), make it a very interesting material and a candidate for use in power electronics and in hazardous environments. LÄS MER