Search for dissertations about: "charge decay"

Showing result 1 - 5 of 69 swedish dissertations containing the words charge decay.

2. 1. Charge transport in polymer-based insulating materials for high voltage applications: effect of single- and multi-layered structures

   Author : Tuan Anh Hoang; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; charge trapping and de-trapping; polyethylene; surface potential decay; enamel insulation; charge transport; charging current; charge injection; charge mobility; DC conductivity; nanocomposite;

   Abstract : Polymer composites have been widely employed as electrical insulating materials for high voltage components and devices such as power cables, gas-insulated systems, rotating machines, line and post insulators, etc. Such materials are usually made by introducing inorganic oxides (SiO2, TiO2, Al2O3, MgO) into polymeric matrices e.g. READ MORE

4. 2. Characterization of Different Interface Types for HVDC Extruded Cable Applications

   Author : Espen Doedens; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polymer surfaces; cable peelings; HVDC; Roughness; Charge injection; XLPE; Field enhancement factors; Schottky injection; DC breakdown; Voltage decay; interfaces; Fowler-Nordheim injection; extruded cable; Roughness assisted charge injection.; Charge decay;

   Abstract : In extruded HVDC cable systems a variety of interface types can be found, and the interfacial properties depend on the application within the system. Such applications can be joints, terminations or the cable itself and they will all have different material combinations and manufacturing methods. READ MORE

5. 3. Electrical Charges on Polymeric Insulator Surfaces and their Impact on Flashover Performance

   Author : Sarath Kumara; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; streamer criterion; polymeric insulation; flashover voltage; surface potential; bulk conductivity; surface conduction; humidity; bulk neutralization; charge decay; Surface charge; silicone rubber; corona charging; gas neutralization;

   Abstract : Utilization of remotely located sustainable energy resources such as solar, wind and hydro calls for further developments of long-distance electric power transmissions operating at ultra-high voltage (UHV) levels which may exceed 1000 kV ac and 800 kV dc utilized today. It is foreseen that insulation of such transmission systems is to be based on polymeric materials that can provide a number of technical benefits over traditionally used glass and porcelain based insulation. READ MORE

6. 4. Surface Charge Dynamics on Polymeric Insulating Materials for High Voltage Applications

   Author : Shahid Alam; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC insulation.; gas neutralization; decay rate; Surface charging; electrical conductivity; surface potential; charge transport; ambient pressure;

   Abstract : To meet increasing demands in electric energy, it is essential to enhance production of electricity from renewable energy sources (solar, wind and hydro). Such generation sites, however, are usually separated from consumption sites by long distances. READ MORE

7. 5. 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