Sökning: "High Voltage Direct Current HVDC"

Visar resultat 1 - 5 av 39 uppsatser innehållade orden High Voltage Direct Current HVDC.

1. 1. Humidity dependent conductivity of air in HVDC applications and the role of surfaces

   Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Fasta tillståndets fysik

   Författare :Erik Svensson; [2023]
   Nyckelord :HVDC; humidity; air conductivity; thin films; HVDC; luftfuktighet; luftkonduktivitet; tunna filmer;

   Sammanfattning : High Voltage Direct Current (HVDC) bushings are insulated devices designed to facilitate the safe passage of electric current across an earthed barrier. Understanding air conductivity is of utmost importance in the design of HVDC components, which is determined by ion density and ion mobility. LÄS MER

3. 2. Control Aid Implementation -Modelling and simulation of triple extruder-

   Master-uppsats, Lunds universitet/Kemiteknik (CI)

   Författare :Karl Langsér; [2023]
   Nyckelord :Machine Learning; Extruder; Modelling; Simulation; Extreme learning machine; Chemical engineering; Technology and Engineering;

   Sammanfattning : In the production of their High Voltage Direct Current Cables (HVDC) and High Voltage Alternating Current Cables (HVAC), NKT uses triple extruders to create layers of insulation and semi-conduction. A model to predict the effect of extruder inputs on the cable’s insulation and semi-conducting layers has been created and trained to predict the extruder in discrete time. LÄS MER

4. 3. Investigation of charge injection at electrode-dielectric interface relevant for HVDC cables : Simulation of charge injection and transport dynamics in electrical insulation for HVDC cables

   Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Tillämpad mekanik

   Författare :Mohammed Mosa; [2023]
   Nyckelord :BCT model; charge injection; space charge density; electric field distribution; Fowler-Nordheim; Richardson-Schottky;

   Sammanfattning : A bipolar charge transport (BCT) model is used to simulate charge injection and transportdynamics inside insulation material which are used in a high voltage direct current (HVDC)cable. Gaining knowledge about space charge density and electric field distribution in theinsulation material enables minimising charge injection at the metal-insulator interface andavoiding unnecessary energy loss. LÄS MER

5. 4. Closed-loop control and data- recording of a modular-multilevel converter (MMC)

   Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

   Författare :Longgang Su; [2022]
   Nyckelord :Modular multilevel converters MMCs ; filed programmable gate array FPGA ; direct memory access DMA ; energy closed-loop control; data recording; ethernet.; Modulära multilevel-omvandlare MMC ; filed programmeable gate array FPGA ; direkt minnesåtkomst DMA ; energistyrning med sluten slinga; datainspelning; ethernet.;

   Sammanfattning : Modular multilevel converters (MMCs) are the preferred converter solution in flexible ac transmission systems (FACTS) and high-voltage direct current (HVDC) applications. This is due to the high quality of the voltage and current signals, lower overall losses, and fewer problems with switching-related EMI. LÄS MER

7. 5. Damping of sub-synchronous control interactions with a STATCOM : Wind farms & series compensated power lines

   Master-uppsats, Uppsala universitet/Institutionen för elektroteknik

   Författare :Leonardo Alvarez Urrutia; [2022]
   Nyckelord :Sub-Synchronous Control Interactions; Power Systems; STATCOM; Network Stability; Doubly-Fed Induction Generator; Impedance-Based Stability Analysis;

   Sammanfattning : The power converter is one of the key components in power system applications such as high voltage direct current (HVDC) systems and the grid connection of intermittent sources such as wind and solar power. However, the increased penetration of converter-based generation introduces challenges, such as sub-synchronous interaction between the converter control system and the grid. LÄS MER