Sökning: "high-frequency switching"

Visar resultat 6 - 10 av 43 avhandlingar innehållade orden high-frequency switching.

1. 6. High-frequency phenomena in small Bi2Sr2CaCu2O8+x intrinsic Josephson junctions

   Författare :Holger Motzkau; Vladimir M. Krasnov; Reinhold Kleiner; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; high-temperature superconductivity; Bi-2212; cuprates; intrinsic Josephson junctions; intrinsic tunneling; fluxons; flux-flow oscillator; THz-emission; cavity resonances; polaritons; electrical doping; micro nano-fabrication; fysik; Physics;

   Sammanfattning : In this thesis, the tunneling between individual atomic layers in structures of Bi2Sr2CaCu2O8+x based high-temperature superconductors are experimentally studied employing the intrinsic Josephson effect. A special attention is paid to the fabrication of small mesa structures using micro and nanofabrication techniques. LÄS MER

3. 7. Modelling and Interference Analysis of AC-DC Converters for Immunity to Voltage Disturbances up to 150 kHz

   Författare :Selcuk Sakar; Sarah Rönnberg; Math Bollen; Sjef Cobben; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AC-DC power converters; electromagnetic compatibility EMC ; high frequency disturbances; supraharmonics; switching converters; interharmonics; conducted disturbances; Electric Power Engineering; Elkraftteknik;

   Sammanfattning : The function of electrical and electronic equipment is challenged by the high frequency emission originated from the more use of switching-based power electronic equipment and Power line communication (PLC) signaling. Investigations have shown that interferences occur in the frequency range between 2 kHz and 150 kHz, e.g. LÄS MER

4. 8. High Frequency (MHz) Planar Transformers for Next Generation Switch Mode Power Supplies

   Författare :Radhika Ambatipudi; Kent Bertilsson; Bengt Oelmann; Jesus Doval Gandoy; Hans-Peter Nee; Torbjörn Thiringer; Göran Thungström; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Planar Magnetics; DC-DC Converters; Switch Mode Power Supplies; MHz Frequency Region;

   Sammanfattning : Increasing the power density of power electronic converters while reducing or maintaining the same cost, offers a higher potential to meet the current trend inrelation to various power electronic applications. High power density converters can be achieved by increasing the switching frequency, due to which the bulkiest parts, such as transformer, inductors and the capacitor's size in the convertercircuit can be drastically reduced. LÄS MER

5. 9. Transient waves in nonstationary media : with applications to lightning and nonlinear media

   Författare :Ingegerd Åberg; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lightning; Klein-Gordon; nonlinear; characteristics; wave splitting; imbedding; sources; propagators; Green functions; direct and inverse scattering; Nonstationary; transient; high-frequency switching; Kerr.; Technological sciences; Teknik;

   Sammanfattning : Propagation of transient waves in nonstationary, inhomogeneous, dispersive, stratified media is considered. Waves originating from sources exterior to the scatterer as well as from internal sources are treated. Algorithms are developed and illustrated by computations of wave phenomena in stationary, nonstationary and weakly nonlinear media. LÄS MER

7. 10. High Frequency (MHz) Resonant Converters using GaN HEMTs and Novel Planar Transformer Technology

   Författare :Hari Babu Kotte; kent Bertilsson; Bengt Oelmann; Noel Shammas; Torbjörn Thiringer; Per Karlsson; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; GaN HEMTs; MHz Frequency; Resonant Converters; Planar Transformer Technology;

   Sammanfattning : The increased power consumption and power density demands of moderntechnologies have increased the technical requirements of DC/DC and AC/DC powersupplies. In this regard, the primary objective of the power supply researcher/engineeris to build energy efficient, high power density converters by reducing the losses andincreasing the switching frequency of converters respectively. LÄS MER