Sökning: "three-phase"

Visar resultat 1 - 5 av 89 avhandlingar innehållade ordet three-phase.

  1. 1. Monolith Reactors in Three-Phase Processes

    Författare :Rolf Edvinsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; desulfurization; methanol synthesis; acetylene hydrogenation; Taylor flow; monolith reactor; three-phase; computational fluid dynamics;

    Sammanfattning : The use of monoliths in chemical processes has been studied with the emphasis on liquid-phase hydrogenations. A monolithic catalyst consists of many narrow, parallel channels with catalytically active species either incorporated into the wall itself or into a layer of a porous oxide deposited on the wall (a washcoat). LÄS MER

  3. 2. Three-phase unbalance of voltage dips

    Författare :Lidong Zhang; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; equipment immunity test; power quality; characterisation; power systems; field measurement; voltage dips sags ; symmetrical components;

    Sammanfattning : .... LÄS MER

  4. 3. Differential Protection for Arbitrary Three-Phase Power Transformers

    Författare :Zoran Gajic; Industriell elektroteknik och automation; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; electric power systems; power transformers; differential protection; power system protection;

    Sammanfattning : This thesis describes how to provide standardized, current based, differential protection for any three-phase power transformer, including phase-shifting transformers with variable phase angle shift and transformers of all construction types and internal on-load tap-changer configurations. The use of standard transformer differential protection for such applications is considered impossible in the protective relaying standards and practices currently applied. LÄS MER

  5. 4. Faults detection and diagnosis for three phase induction machines

    Författare :Mohammed Obaid Mustafa; George Georgoulas; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reglerteknik; Control Engineering;

    Sammanfattning : Three phase induction motors have been intensively utilized in industrial applications, mainly due to their efficiency and reliability. These motors have good properties such as: increased stability and robustness, durability, large power to weight ratio, low production costs and controllability easiness. LÄS MER

  7. 5. Multilevel three-phase dual active bridge dc-dc converters - A study on converter modulation, capacitive energy requirement, ZVS boundaries, MFT's winding connections, and core losses

    Författare :Babak Alikhanzadehalamdari; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high-voltage power converters; dual active bridge; harmonic analysis; three-phase system; medium-frequency transformer; capacitor sizing; multilevel converters; high power-density systems; transformer winding connection; core loss modeling; dc collector network; soft-switching converters;

    Sammanfattning : The collection and transmission of power from offshore wind turbines using dc have advantages over the ac system. One of the enabling technologies for deploying dc collection is the dc-dc converter that boosts the dc output from the turbine to the medium-voltage dc level of the collection grid. LÄS MER