Search for dissertations about: "high voltage impulses"
Showing result 1 - 5 of 9 swedish dissertations containing the words high voltage impulses.
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1. The Effect of HV Impulses on Partial Discharge Activity and on the Dielectric Response in Oil-impregnated Paper Insulation
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
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2. Dielectric Response and Partial Discharge Diagnostics of Insulation Systems by Utilizing High Voltage Impulses
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
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3. The Effects of Lightning on Low Voltage Power Networks
Abstract : The present society is highly dependant on complex electronics systems, which have a low damage threshold level. Therefore, there is a high risk of partial or total loss of the system’s electronics when they are exposed to a thunderstorm environment. READ MORE
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4. Numerical modelling of positive electrical discharges in long air gaps
Abstract : This dissertation deals with research on the numerical modelling of electrical discharges in laboratory long air gaps excited with positive switching impulses. It begins with the preliminary work of several scientists during the last decades, making a detailed analysis of different approaches for modelling all the stages in a full discharge. READ MORE
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5. Effect of HV Impulses on Partial Discharge Activity in Oil-Impregnated Paper Insulation
Abstract : High voltage (HV) transients in electrical power systems are mainly caused by lightning strikes and switching operations. The high voltage transient from its point of origin can propagate in either direction in the electrical power transmission line, and if its magnitude would be below the Basic Insulation Level (BIL) of the equipment for impulse voltage, it can reach the terminals of the equipment without being dissipated by surge arresters. READ MORE