Sökning: "High voltage DC"

Visar resultat 1 - 5 av 154 avhandlingar innehållade orden High voltage DC.

1. 1. 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

3. 2. 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

4. 3. 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

5. 4. High Voltage DC-biased Oil Type Medium Frequency Transformer; A Green Solution for Series DC Wind Park Concept

   Författare :Mohammad Kharezy; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High voltage DC; Insulation design; Offshore wind farm; Leakage inductance; High power isolated DC DC converter; Dual active bridge; Medium-frequency power transformer; Parasitic capacitance; HVDC;

   Sammanfattning : The electric energy generated by remote offshore wind parks is transported to the consumers using high voltage submarine cables. On the generation site, such transmissions are realized today by collecting the energy produced by several wind turbines in a bulky and expensive transformer placed on a dedicated platform. LÄS MER

7. 5. 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