Sökning: "Power cables"

Visar resultat 1 - 5 av 80 avhandlingar innehållade orden Power cables.

  1. 1. Wind-turbine harmonic emissions and propagation through a wind farm

    Författare :Kai Yang; Åke Larsson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Renewable energy; Electric power system; Wind power; Power quality; Power system harmonics; Electric Power Engineering; Elkraftteknik; Energy Engineering; Energiteknik;

    Sammanfattning : The increasing demand for sustainable energy is one of the driving forces behind the increasing use of wind power by means of wind-turbines in electric power systems. Modern wind turbines commonly employ variable-speed-generator technology associated with a power-electronic converter as part of the grid connection. LÄS MER

  3. 2. Power control strategies for renewable energy systems : The inverter's role in future power systems

    Författare :Sara Anttila; Cecilia Boström; Sandra Eriksson; Lena Max; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Renewable energy systems; Grid-connection; Inverter; Power control; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : Connecting more non-dispatchable renewable energy sources (RESs) will result in a higher power variability and a lower system inertia when the synchronous generators are replaced by inverter-connected RES. Inverter control can be divided in three categories: grid-following, grid-forming (GFM) and grid-supporting. LÄS MER

  4. 3. Estimation of electromagnetic material properties with application to high-voltage power cables

    Författare :Yevhen Ivanenko; Sven Nordebo; Martin Norgren; Linnéuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material losses; power cables; cylindrical multipole expansion; Herglotz functions; convex optimization; sum rules; Waves and Signals; Vågor och signaler;

    Sammanfattning : Efficient design of high-voltage power cables is important to achieve an economical delivery of electric power from wind farms and power plants over the very long distances as well as the overseas electric power. The main focus of this thesis is the investigation of electromagnetic losses in components of high-voltage power cables. LÄS MER

  5. 4. Techniques for Localization of Insulation Degradation along Medium-Voltage Power Cables

    Författare :Ruslan Papazyan; Roland Eriksson; Fred Steennis; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical power technology; Attenuation measurement; cross-linked polyethylene insulation; discontinuities; localization; mass-impregnated insulation; numerical analysis; parameter estimation; power cable metallic screen; scattering parameters; time domain reflectometry; velocity measurements; water treeing; Elkraftteknik; Electric power engineering; Elkraftteknik;

    Sammanfattning : Time Domain Reflectometry (TDR) has been used for localization of transmission line discontinuities in diverse applications. Various challenges have to be addressed when applying TDR for localization of insulation degradation in power cables. LÄS MER

  7. 5. Electromagnetic Dispersion Modeling and Analysis for Power Cables

    Författare :Stefan Gustafsson; Sven Nordebo; Alexander Nosich; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; power cable; electromagnetic model; dispersion relation; asymptotic analysis; sensitivity analysis;

    Sammanfattning : This thesis addresses electromagnetic wave propagation in power cables. It consists of five papers, where the three first papers are based on one and the same model, and the last two papers are based on a similar but slightly different model. LÄS MER