Search for dissertations about: "ac ac converters"

Showing result 1 - 5 of 53 swedish dissertations containing the words ac ac converters.

  2. 1. Modeling of Modular Multilevel Converters for Stability Analysis

    Author : Luca Bessegato; Stefan Östlund; Staffan Norrga; Lennart Harnefors; Xiongfei Wang; KTH; []
    Keywords : 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;

    Abstract : 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. READ MORE

  4. 2. Hybrid Converters for HVDC Transmission

    Author : Panagiotis Bakas; Lennart Harnefors; Staffan Norrga; Hans-Peter Nee; Stephen Finney; KTH; []
    Keywords : 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;

    Abstract : 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. READ MORE

  5. 3. Modelling and Interference Analysis of AC-DC Converters for Immunity to Voltage Disturbances up to 150 kHz

    Author : Selcuk Sakar; Sarah Rönnberg; Math Bollen; Sjef Cobben; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AC-DC power converters; electromagnetic compatibility EMC ; high frequency disturbances; supraharmonics; switching converters; interharmonics; conducted disturbances; Electric Power Engineering; Elkraftteknik;

    Abstract : The function of electrical and electronic equipment is challenged by the high frequency emission originated from the more use of switching-based power electronic equipment and Power line communication (PLC) signaling. Investigations have shown that interferences occur in the frequency range between 2 kHz and 150 kHz, e.g. READ MORE

  6. 4. Grid Connected Three-Level Converters : Studies for Wave Energy Conversion

    Author : Remya Krishna; Mats Leijon; Karin Thorburn; Uppsala universitet; []
    Keywords : Wave energy; power converters; control strategies; grid connection; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

    Abstract : This thesis presents an electrical system analysis of a wave energy converter (WEC) for the objective of grid connection. To transfer the enormous amount of power from waves to the load centers, efficient power electronic systems are essential. READ MORE

  7. 5. Modular Battery Systems for Electric Vehicles based on Multilevel Inverter Topologies - Opportunities and Challenges

    Author : Anton Kersten; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dynamic reconfiguration; Energy storage; Energy efficiency; Drive cycle efficiency; Power MOSFET; vehicles; H-bridge; Multilevel systems; Electromagnetic compatibility; Modular battery systems; Battery system performance; Modular multilevel converters; Conduction losses; Electric vehicles; Batteries; Dual battery pack; Cascaded converters; DC-AC power converters; BMS; Common mode noise; Battery modeling; vehicle electrification;

    Abstract : Modular battery systems based on multilevel inverter (MLI) topologies can possibly overcome some shortcomings of two-level inverters when used for vehicle propulsion. The results presented in this thesis aim to point out the advantages and disadvantages, as well as the technical challenges, of modular vehicle battery systems based on MLIs in comparison to a conventional, two-level IGBT inverter drivetrain. READ MORE