Sökning: "DC DC converters"

Visar resultat 16 - 20 av 91 avhandlingar innehållade orden DC DC converters.

1. 16. Modular Battery Systems for Electric Vehicles based on Multilevel Inverter Topologies - Opportunities and Challenges

   Författare :Anton Kersten; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dynamic reconfiguration; Energy storage; Energy efficiency; Drive cycle efficiency; Power MOSFET; vehicles; H-bridge; Multilevel systems; Electromagnetic compatibility; Modular battery systems; Battery system performance; Modular multilevel converters; Conduction losses; Electric vehicles; Batteries; Dual battery pack; Cascaded converters; DC-AC power converters; BMS; Common mode noise; Battery modeling; vehicle electrification;

   Sammanfattning : Modular battery systems based on multilevel inverter (MLI) topologies can possibly overcome some shortcomings of two-level inverters when used for vehicle propulsion. The results presented in this thesis aim to point out the advantages and disadvantages, as well as the technical challenges, of modular vehicle battery systems based on MLIs in comparison to a conventional, two-level IGBT inverter drivetrain. LÄS MER

3. 17. The control of VSC-HVDC and its use for large industrial power systems

   Författare :Cuiqing Du; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VSC-HVDC; inner current controller; outer controller; PWM; dc dc converter; voltage dips; dc networks;

   Sammanfattning : With the recent developments in semiconductors and control equipment, Voltage Source Converter based High Voltage direct Current (VSC-HVDC) has become feasible. Due to the use of VSC technology and Pulse Width Modulation (PWM), it has a number of potential advantages: short circuit current reduction; rapid, independent control of the active and reactive power, etc. LÄS MER

4. 18. Efficient Modeling of Modular Multilevel Converters for HVDC Transmission Systems

   Författare :Noman Ahmed; Hans-Peter Nee; Tim Green; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High-Voltage dc; Modular Multilevel Converter; Voltage-Source Converter; HVDC Grids; Multiterminal DC Systems; Hybrid HVDC Breaker; Modeling; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : The drive towards getting more and more electrical energy from renewable sources, requires more efficient electric transmission systems. A stronger grid, with more controllability and higher capacity, that can handle power fluctuations due to a mismatch between generation and load is also needed. LÄS MER

5. 19. On Gate Drivers for MOS-Controlled Power Devices and dv-dt Filters for Train Traction Converters

   Författare :Erik Velander; Hans-Peter Nee; Francesco Iannuzzo; KTH; []
   Nyckelord :Power semiconductor devices; DC-AC power converters; Silicon carbide; Insulated gate bipolar transistors; P-i-n diodes; Schottky diodes; Traction motors; Power MOSFET; Krafthalvledare; DC-AC kraftomvandlare; kiselkarbid; IGBT; P-i-n dioder; Schottky dioder; traktionsmotorer; Effekt-MOSFET; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : In this thesis, low-loss gate-drive solutions and a proposed dv/dt-filter have been investigated with focus on train traction converters with dv/dt constraints.By using the silicon carbide (SiC) junction field-effect transistor (JFET), the switching losses can be significantly reduced compared to the commonly used insulated-gate bipolar transistor (IGBT), but complex gate-driver solutions are required for high utilization in terms of loss reduction. LÄS MER

7. 20. On small-signal analysis and control of the single- and the dual-active bridge topologies

   Författare :Georgios D. Demetriades; Hans-Peter Nee; Jorma Kyyrä; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronics; DC-DC converters; Soft-switching; High-frequency; High-power; Bi-directional; Single-Active Bridge; Elektronik; Electronics; Elektronik;

   Sammanfattning : High-frequency dc-dc converters are nowadays widely used in a diversity of power electronic applications. High operating frequencies entail a reduction in size of the passive components, such as inductors, capacitors and power transformers. LÄS MER