Sökning: "electrical ageing"

Visar resultat 1 - 5 av 54 avhandlingar innehållade orden electrical ageing.

  1. 1. Mechanisms of Electrical Ageing of Oilimpregnated Paper due to Partial Discharges

    Författare :Mohamad Ghaffarian Niasar; Hans Edin; Ernst Gockenback; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; partial discharges; oil-impregnated paper; oil; transformer insulation; dielectric frequency response; breakdown strength; ion mobility; thermal ageing; electrical ageing; moisture in paper; life time; thermal breakdown.; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : In this thesis, partial discharge (PD) phenomenon in oil-impregnated paper (OIP) is investigated under accelerated electrical stress. The thesis is mainly focused on the characteristic of PD activity and the influence it has on the insulation properties of OIP. LÄS MER

  3. 2. On reliability modelling of ageing equipment in electric power systems with regard to the effect of maintenance

    Författare :Tommie Lindquist; Prof. Roland Eriksson; Dr. Lina Bertling; Docent Carl-Ejnar Sölver; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical power technology; Maintenance; reliability modelling; electrical power systems; ageing; failure mechanisms; Elkraftteknik; Electric power engineering; Elkraftteknik;

    Sammanfattning : Power system maintenance optimisation involves obtaining the minimum total costs, including preventive and corrective maintenance costs and the cost of failures for both supplier and customer. To calculate the cost of failure, information is needed about the equipment reliability characteristics. LÄS MER

  4. 3. Ageing and characterisation of semiconducting glazes

    Författare :Heike Ullrich; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; outdoor insulation; HV-DC AC system; field monitoring; semiconducting surface insulator; ageing; laboratory testing;

    Sammanfattning : .... LÄS MER

  5. 4. Experimental investigations of ageing of commercial BEV Li-ion batteries

    Författare :Kristian Bartholdsson Frenander; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silicon oxide; lithium plating; ageing; Physics-based modelling; Electric Vehicles; Lithium Ion Batteries; lifetime; NCA; State of Charge;

    Sammanfattning : The rapid development of lithium-ion batteries has enabled changes in widespread applications ranging from portable electronics to electric vehicles and large scale grid energy storage. However, battery ageing remain a challenge in all these applications, and this thesis seeks to contribute to the understanding of Li-ion battery degradation. LÄS MER

  7. 5. Influence of Ageing on Material Properties at Interfaces in Composite Insulators

    Författare :Johan Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; composite insulators; ageing; silicone rubber; salt fog test; Outdoor insulation; inclined plane test; interfaces;

    Sammanfattning : High quality of internal interfaces in composite insulators for high voltage applications is necessary for securing durability of their functionality. Weak macroscopic interfaces between the glass fibre reinforced (FRP) epoxy core and the silicone rubber (SIR) housing, such as spots with reduced bonding or a loss of the adhesion as well as presence of foreign contaminants, can appear to have an accelerating effect on the evolution of ageing processes, though it may take years before the first signs of processes endangering the insulator function appear. LÄS MER