Sökning: "High-Voltage dc"

Visar resultat 1 - 5 av 63 avhandlingar innehållade orden High-Voltage dc.

1. 1. Thermoplastic Insulation for High Voltage Cables

   Författare :Yingwei Ouyang; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polyethylene; insulation; polypropylene; blends; thermoplastic; high voltage; polymer;

   Sammanfattning : High voltage direct current (HVDC) cables that seamlessly integrate renewables have an important contribution to the modern world’s efforts towards a more sustainable future. Extruded HVDC cables that efficiently and reliably transport electricity require robust insulation materials with good thermomechanical and dielectric properties. LÄS MER

3. 2. Charge Accumulation in Hybrid High Voltage Insulation

   Författare :Mats Sjöberg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dielectric barrier; charge accumulation; high voltage; dielectric barrier discharge; dielectric coating; hybrid insulation; electric field distribution; discharge modelling; breakdown strength; charge conditioning;

   Sammanfattning : This thesis deals with the novel idea of controlling the electric stress or field distribution in a hybrid air - solid-dielectric high voltage insulation by promoting accumulation of surface charges on the internal interfacial layers in the combined (hybrid) dielectric structure. Primarily, applications are expected to be found in high voltage dc systems and as a method to improve the resistance against insulation failure by overvoltages, e. LÄS MER

4. 3. On high-frequency soft-switching DC-converters for high-voltage applications

   Författare :Per Ranstad; KTH; []
   Nyckelord :soft-switching; dc-converter; high-frequency; high-voltage;

   Sammanfattning : .... LÄS MER

5. 4. Control and Design Aspects of Components and Systems in High-Voltage Converters for Industrial Applications

   Författare :Per Ranstad; Hans-Peter Nee; Alfred Rufer; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High-voltage converter; resonant converter; high-voltage transformer; transformer parasitics; IGBT; soft-switching; control; Electric power engineering; Elkraftteknik;

   Sammanfattning : High-frequency dc-dc converters are widely used in power electronic applications, both in consumer products and industrial products. By operating the converter at higher frequencies both a smaller size and better control characteristics can be obtained. LÄS MER

7. 5. Silicon-Carbide-Based High-Voltage Submodules for HVDC Voltage-Source Converters

   Författare :Keijo Jacobs; Hans-Peter Nee; Staffan Norrga; Marc Hiller; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Silicon carbide; HVDC converters; voltage source converters; modular multilevel converters; submodule topologies; metal-oxide-semiconductor field-effect transistor MOSFET ; insulated-gate bipolar-transistor IGBT ; power semiconductor devices; high-voltage; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : In order to transition to renewable energy sources and simultaneously meet the increasing demand for electrical energy, highly flexible and efficient grids are required. High-voltage direct-current (HVDC) transmission and grids are foreseen to be a vital part of the future electricity grid. LÄS MER