Search for dissertations about: "bushing"

Showing result 1 - 5 of 11 swedish dissertations containing the word bushing.

2. 1. Engineering rubber bushing stiffness formulas including dynamic amplitude dependence

   Author : Maria-José Garcia; Leif Kari; Anders Ågren; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Construction engineering; Konstruktionsteknik;

   Abstract : Engineering design models for the torsion and axial dynamic stiffness of carbon black filled rubber bushings in the frequency domain including amplitude dependence are presented. They are founded on a developed material model which is the result of applying a separable elastic, viscoelastic and friction rubber component model to the material level. READ MORE

4. 2. Diagnostics of Oil-Impregnated Paper Insulation Systems by Utilizing Lightning and Switching Transients

   Author : Roya Nikjoo; Hans Edin; Christer Törnkvist; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Capacitance; Dielectric Response; Loss tangent; Moisture content; Oil - impregnated paper; Temperature; Transformer Bushing; Transients;

   Abstract : Development of the power gridtowards a more reliable and smarter system requires frequent on-line monitoring of the power components. Power transformers and their bushings are particularly important components in a power transmission system and their insulation degradation may lead to catastrophic failures. READ MORE

5. 3. Dielectric Response and Partial Discharge Diagnostics of Insulation Systems by Utilizing High Voltage Impulses

   Author : Roya Nikjoo; Hans Edin; Andrea Cavallini; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dielectric Response; Transients; Transformer bushing; Oil-impregnated paper; Moisture content; Partial discharge; Surface PD; Cavity PD; Superimposed impulse; Nanoparticles; Electrical Engineering; Elektro- och systemteknik;

   Abstract : In this thesis, power system transients are considered as an opportunity for development of on-line diagnostics of power components and specifically the insulation systems of power transformers and bushings.A new technique for on-line dielectric response measurement of power transformer bushings is proposed which utilizes natural transients in the power system, such as lightning and switching surges, as stimuli. READ MORE

6. 4. Magneto-sensitive rubber in the audible frequency range

   Author : Peter Blom; Leif Kari; Luigi Bregant; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magneto-sensitivity; Rubber; Audible frequency range; Amplitude dependence; Vibration isolator; Fletcher-Gent effect; Stiffness; Acoustics; Akustik;

   Abstract : The dynamic behaviour in the audible frequency range of magneto-sensitive (MS) rubber is the focus of this thesis consisting of five papers A-E. Paper A presents results drawn from experiments on samples subjected to different constant shear strains over varying frequencies and magnetic fields. READ MORE

7. 5. The Effect of HV Impulses on Partial Discharge Activity and on the Dielectric Response in Oil-impregnated Paper Insulation

   Author : Respicius Clemence Kiiza; Hans Edin; Jörgen Blennow; KTH; []
   Keywords : Partial discharge; high voltage impulses; oil-impregnated paper; dielectric spectroscopy; Finite Element Method.;

   Abstract : This work investigates how HV impulses affect the behavior of partial discharge (PD) activity and the low voltage dielectric response of oil-impregnated paper insulation. It also investigates how the change in the PD activity is related to the degradation level of oil-impregnated paper insulation. READ MORE