Sökning: "Magnetization measurements"

Visar resultat 1 - 5 av 62 avhandlingar innehållade orden Magnetization measurements.

  1. 1. Magnetization Dynamics in Ferromagnetic Thin Films : Evaluation of Different Contributions to Damping in Co2FeAl and FeCo Film Structures

    Författare :Serkan Akansel; Peter Svedlindh; Olof Karis; Erik Wahlström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spintronics; Gilbert damping parameter; magnetization dynamics; ferromagnetic resonance; Heusler alloys; magnetic thin films; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : Static and dynamic magnetic properties of Co2FeAl and Fe65Co35 alloys have been investigated. Co2FeAl films were deposited at different temperatures and the deposition parameters were optimized with respect to structural and magnetic properties. As a result, a film with B2 crystalline phase was obtained without any post-annealing process. LÄS MER

  3. 2. Electromagnetic Modelling of Power Transformers with DC Magnetization

    Författare :Seyed Ali Mousavi; Göran Engdahl; S. V. Kulkarni; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transformer; Hysteresis; DC magnetization; GICs; FEM; reluctance network method;

    Sammanfattning : DC currents that flow through the ground can be injected to the star windings of power transformers from their grounded neutral points and close their path with transmission lines. The geomagnetically induced currents (GICs) and AC/DC convertors of high voltage direct current (HVDC) systems are the sources of such DC currents. LÄS MER

  4. 3. Constructing and Commissioning HELIOS – A High Harmonic Generation Source for Pump-Probe Measurements with sub 50 fs Temporal Resolution : The Development of Experimental Equipment for Extreme Ultraviolet Spectroscopy

    Författare :Joachim A. Terschlüsen; Johan Söderström; Margaret Murnane; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Angle-resolved photoemission spectroscopy; Angle resolved photoemission spectroscopy; Angle-resolved time-of-flight; Angle resolved time of flight; ARTOF; ARPES; tr-ARPES; fs; fs resolution; Fourier transform spectrometer; Fourier-transform spectrometer; Fourier transform spectroscopy; Fourier-transform spectroscopy; FTS; gas cell; high harmonic generation; laser; liquid jet; monochromator; HELIOS; HHG; off-plane mount; off plane mount; OPA; optical parametric amplifier; PCPDTBT; pulse shaping; pump probe; pump-probe measurements; pump-probe measurements; pump-probe spectroscopy; pump-probe spectroscopy; Rowland spectrometer; time-of-flight spectrometer; time of flight spectrometer; TOF; time-resolved spectroscopy; time resolved spectroscopy; time-resolved experiments; time resolved experiments; T-MOKE; tr-PES; PES; photoelectron spectroscopy; transverse magneto optical Kerr effect; transverse magneto-optical Kerr effect; ultrafast; ultra-high vacuum; ultra high vacuum; UHV; XUV; VUV; X-rays; Permalloy; magnetization dynamic; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : This thesis presents HELIOS, an in-house laboratory for time-resolved pump-probe spectroscopy with extreme-ultraviolet (XUV) probe radiation. A wide span of pump wavelengths can be generated using commercial laser equipment while XUV probe radiation is generated via a high harmonic generation process in a noble gas delivering probe photons with energies between 20 eV and 72 eV. LÄS MER

  5. 4. Electromagnetic transformer modelling including the ferromagnetic core

    Författare :David Ribbenfjärd; Göran Engdahl; David Jiles; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Power transformer; hysteresis; dynamic hysteresis; dynamic magnetization; eddy currents; excess losses; leakage flux; winding model; core model; magnetic measurements; magnetic materials; Electric power engineering; Elkraftteknik;

    Sammanfattning : In order to design a power transformer it is important to understand its internal electromagnetic behaviour. That can be obtained by measurements on physical transformers, analytical expressions and computer simulations. LÄS MER

  7. 5. Magnetizing Currents in Power Transformers : Measurements, Simulations, and Diagnostic Methods

    Författare :Claes Carrander; Hans Edin; Göran Engdahl; Rajeev Thottappillil; Amr Adly; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transformer core; diagnostics; three-phase; no-load; hysteresis; modeling; resonance; remanence; delta; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : This thesis demonstrates a method for transformer core diagnostics. The method uses the no-load current of the transformer as an indicator, and gives different characteristic signatures for different types of faults or defects. Using the no-load current for the diagnostic gives high sensitivity. LÄS MER