Search for dissertations about: "magnetic leakage fields"

Found 5 swedish dissertations containing the words magnetic leakage fields.

  2. 1. Magnetic Leakage Fields and End Region Eddy Current Power Losses in Synchronous Generators

    Author : Birger Marcusson; Urban Lundin; Göran Engdahl; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; magnetic leakage fields; leakage flux; eddy currents; losses; synchronous generator; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : The conversion of mechanical energy to electrical energy is done mainly with synchronous generators. They are used in hydropower generators and nuclear plants that presently account for about 80% of the electric energy production in Sweden. READ MORE

  4. 2. Application of 3-D Computation of Magnetic Fields to the Design of Claw-Pole Motors

    Author : Sonja Lundmark; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : The main advantage of claw-pole machines lies in their ability to yield higher torque density values than is obtainable from a conventional machine. However, the high torque density has its price; leakage flux is often high resulting in low power factor and efficiency. READ MORE

  5. 3. On the System Optimization of Magnetic Circuit with Alternative Permanent Magnets and its Demagnetization

    Author : Jonathan Sjölund; Sandra Eriksson; Leijon Mats; Sami Ruoho; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Permanent magnet machines; Finite element method; ferrite permanent magnets; linear machines; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : Permanent magnet (PM) machines are often associated with the usage of rare earth magnets, due to their high energy density. One such rare earth magnet is the neodymium-iron-boron (NdFeB), which is mainly produced in China. Due to the global scarcity of the rare earth magnets, much interest is put into utilizing other permanent magnet materials. READ MORE

  6. 4. Semiconductor Nanoelectronic Devices Based on Ballistic and Quantum Effects

    Author : Jie Sun; Fasta tillståndets fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Semiconductor; Quantum Dots; Ballistic Transport; InGaAs InP 2DEG; Nanoelectronics;

    Abstract : As current silicon-based microelectronic devices and circuits are approaching their fundamental limits, the research field of nanoelectronics is emerging worldwide. With this background, the present thesis focuses on semiconductor nanoelectronic devices based on ballistic and quantum effects. The main material studied was a modulation doped In0. READ MORE

  7. 5. Spectroscopic studies of InGaAs/GaAs/A1GaAs quantum dots and wires

    Author : Fredrik Karlsson; Manfred Bayer; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : It is demonstrated that the photoluminescence (PL) spectra of single selfassembled lnAs/GaAs quantum dots (QDs) are very sensitive to excitation energy and crystal temperature, which is explained in terms of modulation of the effective diffusivity of the photogenerated carriers affecting the capture probability into theQD. This effect results in a population of the QD with excess electrons, and can be used as a simple tool to create and study charged exciton complexes. READ MORE