Search for dissertations about: "corona discharge"

Showing result 6 - 10 of 23 swedish dissertations containing the words corona discharge.

  2. 6. Electrical Characterization of Partial Discharge Resistant Enamel Insulation

    Author : Tuan Anh Hoang; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Enamel wire insulation; dipolar polarization; charge injection; charge transport; chromium oxide; dc conductivity; partial discharge; twisted pair.; dielectric permittivity;

    Abstract : Adjustable speed drives for rotating machines have become increasingly popular as they provide possibilities of smooth and accurate process control as well as for energy savings. In such systems, due to the fact that the voltage applied at terminals of motor windings is no longer purely sinusoidal but characterized by a high content of harmonics, the appearing electrical and thermal stresses yield premature failures of the winding insulation, mainly because of an increased partial discharge (PD) activity. READ MORE

  4. 7. Electrical Charges on Polymeric Insulator Surfaces and their Impact on Withstand Performance

    Author : Sarath Kumara; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; impulse corona; Surface charge; impulse flashover voltage; corona charging; streamer criterion; surface potential decay; charge relaxation;

    Abstract : Use of polymeric materials for high voltage outdoor insulation systems is increasing continuously. Insulating polymers gradually replace traditional materials like porcelain and glass and become dominant at ultra high voltages, e.g., in 1000 kV ac and 800 kV dc overhead power transmissions, which are presently being developed. READ MORE

  5. 8. Polymer-coated paper and board - Role of substrate, polymer characteristics and additives

    Author : Thomas Schuman; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; surface energy; latex; surface roughness; corona; contact angle; barrier properties; liquid sorption; surface treatment; calendering; poly vinyl alcohol ; coating;

    Abstract : The surface roughness of paper or board has a significant influence on the homogeneity of an applied polymer film, and this thesis discusses how it may be improved by a surface treatment, e.g. high-temperature calendering or precoating. READ MORE

  6. 9. From Macro to Nano : Electrokinetic Transport and Surface Control

    Author : Gaspard Pardon; Wouter van der Wijngaart; Philippe Renaud; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microsystem; nanosystem; microfluidic; nanofluidic; surface modification; surface property; electrokinetics; model; simulation; material; polymer; thiol-ene; microfabrication; nanofabrication; micromanufacturing; nanomanufacturing; breath sampling; aerosol precipitation; corona discharge; electrostatic precipitation; grafting chemistry; click chemistry; nanopore; nanoporous membrane; photolithography; photopatterning; photografting; microfluidics; nanofluidics; oste; OSTE ; OSTEmer; lab-on-chip; loc; point-of-care; poc; biocompatibility; diagnostics; breath analysis; fuel cell; Electrical Engineering; Elektro- och systemteknik; Teknisk materialvetenskap; Materials Science and Engineering; Fysik; Physics; Medical Technology; Medicinsk teknologi;

    Abstract : Today, the growing and aging population, and the rise of new global threats on human health puts an increasing demand on the healthcare system and calls for preventive actions. To make existing medical treatments more efficient and widely accessible and to prevent the emergence of new threats such as drug-resistant bacteria, improved diagnostic technologies are needed. READ MORE

  7. 10. Partial Discharge Signatures of Defects in Insulation Systems Consisting of Oil and Oil-impregnated Paper

    Author : Mohamad Ghaffarian Niasar; Hans Edin; Peter Werelius; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; partial discharge; transformer; oil; ageing; temperature; PD classification;

    Abstract : Partial discharge measurement is a common method for monitoring and diagnostics of power transformers, and can detect insulation malfunctions before they lead to failure. Different parameters extracted from the measured PD activity can be correlated to the PD source, and as a result it is possible to identify the PD source by analyzing the PD activity. READ MORE