Sökning: "power conversion"

Visar resultat 6 - 10 av 442 avhandlingar innehållade orden power conversion.

  1. 6. High-Efficiency SiC Power Conversion : Base Drivers for Bipolar Junction Transistors and Performance Impacts on Series-Resonant Converters

    Författare :Georg Tolstoy; Hans-Peter Nee; Stig Munk-Nielsen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Silicon Carbide; Bipolar Junction Transistor BJT ; Resonant converter; Series-resonant converter SLR ; Base drive circuits; High- Efficiency Converters; High-Frequency Converters; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : This thesis aims to bring an understanding to the silicon carbide (SiC) bipolar junction transistor (BJT). SiC power devices are superior to the silicon IGBT in several ways. They are for instance, able to operate with higher efficiency, at higher frequencies, and at higher junction temperatures. LÄS MER

  2. 7. Ansikte mot ansikte. Räddningsarbete bland prostituerade kvinnor i Sverige 1850-1920

    Författare :Anna Jansdotter; Historia; []
    Nyckelord :HUMANIORA; HUMANITIES; Contemporary history circa 1800 to 1914 ; private space.; public space; difference; ideology; power; women; gender; conversion; revivalist movement; social work; rescue work; reform movement; prostitution; Sweden; 1850-1920; Modern historia ca. 1800-1914 ; Contemporary history since 1914 ; Nutidshistoria från 1914 ;

    Sammanfattning : The object of this thesis is a Swedish religious reform movement that, from mid nineteenth century to early twentieth century, undertook social work intended to ‘rescue’ female prostitutes. The purpose of the study is to illuminate the encounter between two groups of women, the rescuers and the rescued. LÄS MER

  3. 8. Marine Current Energy Conversion

    Författare :Staffan Lundin; Mats Leijon; AbuBakr S. Bahaj; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; marine current energy; renewable energy; turbine; energy conversion; wake; Söderfors; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : Marine currents, i.e. water currents in oceans and rivers, constitute a large renewable energy resource. This thesis presents research done on the subject of marine current energy conversion in a broad sense. LÄS MER

  4. 9. 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. 10. Buoy and Generator Interaction with Ocean Waves : Studies of a Wave Energy Conversion System

    Författare :Simon Lindroth [formerly Tyrberg]; Mats Leijon; Brian Holmes; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wave power; Measurement systems; Marine technology; Energy conversion; Renewable energy; Energy absorption; Wave resource; Oceanic engineering; Linear generators; Point absorbers; Sea trials; Camera systems; Accelerometers; Offshore experiments; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : On March 13th, 2006, the Division of Electricity at Uppsala University deployed its first wave energy converter, L1, in the ocean southwest of Lysekil. L1 consisted of a buoy at the surface, connected through a line to a linear generator on the seabed. LÄS MER