Sökning: "HVDC isolation"
Visar resultat 1 - 5 av 6 avhandlingar innehållade orden HVDC isolation.
1. Polyethylene/metal oxide nanocomposites for electrical insulation in future HVDC-cables : probing properties from nano to macro
Sammanfattning : Nanocomposites of polyethylene and metal oxide nanoparticles have shown to be a feasible approachto the next generation of insulation in high voltage direct current cables. In order to reach an operationvoltage of 1 MV new insulation materials with reduced conductivity and increased breakdown strengthas compared to modern low-density polyethylene (LDPE) is needed. LÄS MER
2. Characterization of Conduction and Polarization Properties of HVDC Cable XLPE Insulation Materials
Sammanfattning : Since its first introduction in 1998, extruded direct current (DC) cable technology has been growing rapidly leading to many cable system installations with operation voltages up to 320 kV. Cable manufacturers invest heavily on technology development in this field and today extruded DC cable systems for operation voltages as high as 525 kV are commercially available. LÄS MER
3. Polyethylene – metal oxide particle nanocomposites for future HVDC cable insulation : From interface tailoring to designed performance
Sammanfattning : Low-density polyethylene (LDPE) nanocomposites containing metal oxide nanoparticles are considered as promising candidates for insulating materials in future high-voltage direct-current (HVDC) cables. The significant improvement in dielectric properties compared with unfilled polymer is attributed to the large and active interface between the nanoparticles and the polymer. LÄS MER
4. Measuring degradation in cable insulation material under realistic operation conditions
Sammanfattning : One of the challenges in laboratory investigation of degradation and ageing of HVDC cable insulation is related to securing, or in other words, imitating the real service environment of the material specimens. So far, the published data refer to experiments conducted in thermo-oxidative conditions, which is not the case during normal cable operation. LÄS MER
5. Design and Optimization of HF Transformers for High Power DC-DC Applications
Sammanfattning : Increasing the operational frequency is the most common solution to achieve higherpower densities, since the weight and volume of the magnetic part, the bulkiestelement in power electronics converters, are then decreased. This solution is wellestablished in low power high frequency applications, while in the recent decade,the possibility of utilizing high frequency at higher power and voltage levels hasgenerated wide interest as well. LÄS MER