Sökning: "dielectric spectroscopy"

Visar resultat 6 - 10 av 90 avhandlingar innehållade orden dielectric spectroscopy.

1. 6. Dielectric properties of poly(ethyelene-co-butyl acrylate) filled with Alumina nanoparticles

   Författare :Nadejda Jäverberg; Hans Edin; Eva Mårtensson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nanocomposites; poly ethylene-co-butyl acrylate ; EBA; alumina; dielectric permittivity; absorbed water; humidity; temperature; dielectric spectroscopy; partial discharge; electrical treeing; Electrical engineering; Elektroteknik;

   Sammanfattning : In this work dielectric properties of the poly(ethylene-co-butyl acrylate)filled with alumina nanoparticles are evaluated. These nanocomposite materialswere manufactured at the department of Fibre and Polymer Technology,KTH.This study is limited to the properties of general importance for the AC applications. LÄS MER

3. 7. Development and application of high voltage dielectric spectroscopy for diagnosis of medium voltage XLPE cables

   Författare :Peter Werelius; KTH; []
   Nyckelord :dielectric spectroscopy; high voltage; variable frequency; diagnostics; non-disgnostics;

   Sammanfattning : When polymer power cables were introduced into mediumvoltage applications in the late 1960s, the degradationphenomenon later referred to aswater treeingwas still unknown. However, this changedwithin a relatively short space of time. LÄS MER

4. 8. Dielectric relaxation spectroscopy of chiral smectic liquid crystals

   Författare :Fathi M. Gouda; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dielectric relaxation measurement; goldstone mode; liquid crystals; ; soft mode; polarisation mode; perpendicular component; tilt fluctuation;

   Sammanfattning : .... LÄS MER

5. 9. Partial discharges studied by dielectric response method

   Författare :Xiangdong Xu; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency domain spectroscopy; AWIS; partial discharge excess current; dielectric characterization; partial discharge; non-PD excess current;

   Sammanfattning : The increasing demand of integrating various renewable energy recourses in power system requires extensive use of power electronic solutions, which allows energy conversion between different frequencies and stabilizes the system. Consequently, other than the traditional 50/60 Hz sinusoidal voltage stresses act on the high voltage insulation systems. LÄS MER

7. 10. Electrical Insulating Properties of Poly(Ethylene-co-Butyl Acrylate) Filled with Alumina Nanoparticles

   Författare :Nadejda Jäverberg; Hans Edin; John Fothergill; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nanocomposites; poly ethylene-co-butyl acrylate ; EBA; alumina; dielectric permittivity; absorbed water; humidity; temperature; dielectric spectroscopy; breakdown strength; pre-breakdown current;

   Sammanfattning : In this work the electrical insulating properties of the nanocomposite materials based on poly(ethylene-co-butyl acrylate) filled with alumina nanoparticles are studied. The dielectric properties chosen for the evaluation are the dielectric permittivity and loss as well as the breakdown strength and the pre-breakdown currents. LÄS MER