Search for dissertations about: "Saturation"

Showing result 21 - 25 of 486 swedish dissertations containing the word Saturation.

  2. 21. Automating Power Quality Analysis

    Author : Emmanouil Styvaktakis; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pattern classification; expert systems; induction motors; power system transients; voltage dips; power system faults; power quality; Kalman filtering; power system monitoring; transformer saturation; short time Fourier transform;

    Abstract : The increased requirements on supervision, control, and performance in modern power systems make power quality monitoring a common practise for utilities. Large databases are created and automatic processing of the data is required for fast and effective use of the available information. READ MORE

  4. 22. On Power-system Benefits, Main-circuit Design, and Control of StatComs with Energy Storage

    Author : Hailian Xie; Hans-Peter Nee; Lennart Ängquist; Timothy Green; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy storage; Voltage source converter; VSC; Static synchronous compensation; StatCom; Active power compensation; Phase jump; Voltage dip; Weak network; Flux modulation; Deadbeat current control; Transformer saturation; Dual thyristor converter; dc interface; Electrical engineering; Elektroteknik; Electric power engineering; Elkraftteknik;

    Abstract : Static synchronous compensation (StatCom) is an application that utilizes a voltage source converter (VSC) to provide instantaneous reactive power support to the connected power system. Conventionally, StatComs are employed for reactive power support only. READ MORE

  5. 23. Effects of impurities on charge transport in graphene field-effect transistors

    Author : Marlene Bonmann; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carrier transport; electron and hole mobility; impurities; traps; graphene; field-effect transistors; microwave devices; saturation velocity; remote phonons;

    Abstract : In order to push the upper frequency limit of high speed electronics further, thereby extending the range of applications, new device technologies and materials are continuously investigated. The 2D material graphene, with its intrinsically extremely high room temperature charge carrier velocity, is regarded as a promising candidate to push the frequency limit even further. READ MORE

  6. 24. Materials for Magnetic Recording Applications

    Author : Till Burkert; Olle Eriksson; Lars Nordström; Stefan Blügel; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; magnetic materials; magnetic anisotropy; saturation magnetization; magnetic data storage; superlattice; hydrogen; density functional theory; first-principles calculations; two-dimensional magnetism; FP-LMTO; EXAFS; MOKE; Fysik; Physics; Fysik;

    Abstract : In the first part of this work, the influence of hydrogen on the structural and magnetic properties of Fe/V(001) superlattices was studied. The local structure of the vanadium-hydride layers was determined by extended x-ray absorption fine structure (EXAFS) measurements. READ MORE

  7. 25. Influence of Composition and Pore Geometry on Immiscible Fluid Flow through Greensands: Development of Neutron Transmission Methods and Image Analysis

    Author : Mikael Solymar; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; pore geometry; image analysis; fluid flow; petrography; greensand; porosity; glauconite; permeability; neutron transmission methods; fluid saturation;

    Abstract : The effect of the mineralogical composition and pore geometry of sediments on the distribution as well as the flow of immiscible fluids are of importance when evaluating petroleum reservoirs. Greensand containing the clay mineral glauconite is a complex reservoir rock type. READ MORE