Search for dissertations about: "DIELECTRIC RESPONSE, OIL PAPER"

Showing result 1 - 5 of 12 swedish dissertations containing the words DIELECTRIC RESPONSE, OIL PAPER.

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

   Author : Mohamad Ghaffarian Niasar; Hans Edin; Ernst Gockenback; KTH; []
   Keywords : 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;

   Abstract : 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. READ MORE

4. 2. Enhanced Dielectric Response Methods for the Characterization of Dielectric Materials

   Author : Jing Hao; Nathaniel Taylor; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; FDS; non-contact; dielectric response; combined AC and DC; space-charge polarization;

   Abstract : Dielectric response measurement is widely used for condition assessment of high voltage equipment and for characterizing candidate materials. Measurement with high accuracy and reliability is important in all stages of the lifetime of high voltage equipment, from manufacture to replacement decision. READ MORE

5. 3. 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

6. 4. 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

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