Sökning: "Staffan Norrga"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden Staffan Norrga.

  1. 1. On soft-switching isolated AC/DC converters without auxiliary circuit

    Författare :Staffan Norrga; Stefan Östlund; Rik De Doncker; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical power technology; voltage source converter; cycloconverter; isolated converter; medium frequency transformer; soft switching; modulation; commutation; wind power; electric traction; Elkraftteknik; Electric power engineering; Elkraftteknik;

    Sammanfattning : The thesis is concerned with a class of power electronic converter systems that permit bidirectional AC/DC conversion with galvanic separation of the AC and DC sides by a transformer operating at elevated frequency. The systems consist of a capacitively snubbered voltage source converter and a cycloconverter, separated by the mentioned transformer. LÄS MER

  3. 2. Hybrid Converters for HVDC Transmission

    Författare :Panagiotis Bakas; Lennart Harnefors; Staffan Norrga; Hans-Peter Nee; Stephen Finney; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High-voltage direct current HVDC ; hybrid alternate-common arm converter HACC ; hybrid converters; line-commutated converters LCCs ; modular multilevel converters MMCs ; thyristors; Hybrid alternate-common-arm converter HACC ; hybrid omvandlare; högspänd likströmsöverföring HVDC ; linjekommuterade omvandlare LCC ; modulära multinivåomvandlare MMC ; tyristorer; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : The line-commutated converter (LCC) and the voltage-source converter (VSC) are the two main converter technologies utilized in high-voltage direct current (HVDC) transmission applications. Depending on the application requirements, one technology might be more advantageous than the other. LÄS MER

  4. 3. Modeling of Modular Multilevel Converters for Stability Analysis

    Författare :Luca Bessegato; Stefan Östlund; Staffan Norrga; Lennart Harnefors; Xiongfei Wang; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Modular multilevel converters MMCs ; stability; admittance; frequency-domain analysis; linearization techniques; current control; voltage control; ac ac converters; railway engineering.; Modulära multinivåomvandlare MMC ; stabilitet; admittans; frekvensanalys; linjäriseringsmetoder; strömreglering; spänningsreglering; ac ac omvandlare; järnvägsteknik.; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Modular multilevel converters (MMCs) have recently become the state-of-the-art solution for various grid-connected applications, such as high-voltage direct current (HVDC) systems and flexible alternating current transmission systems (FACTS). Modularity, scalability, low power losses, and low harmonic distortion are the outstanding properties that make MMCs a key technology for a sustainable future. LÄS MER

  5. 4. Wireless Control of Modular Multilevel Converter Submodules

    Författare :Baris Ciftci; Hans-Peter Nee; Lennart Harnefors; Staffan Norrga; James Gross; Lars Kildehöj Rasmussen; Remus Teodorescu; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 5G mobile communication; autonomous control; converter control; distributed control; electromagnetic interference; emerging technology; fault ride-through; modular multilevel converter MMC ; prototype; wireless control; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : The modular multilevel converter (MMC) has extensively been used in high-voltage, high-power applications such as high-voltage dc transmission systems and flexible alternating current transmission systems. The control of MMC submodules is conventionally realized using wired communication systems. LÄS MER

  7. 5. Modulation of Modular Multilevel Converters for HVDC Transmission

    Författare :Arman Hassanpoor; Hans-Peter Nee; Staffan Norrga; Rainer Marquardt; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC; switching schemes; modulation; high power converters; power grids; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : The outstanding features of modular multilevel converters (MMC) have recently gained much attention in the high-voltage direct-current (HVDC) transmission field. Power quality, converter cost and system performance are three crucial aspects of HVDC MMCs which are directly linked to the converter modulation and switching schemes. LÄS MER