Search for dissertations about: "dc drive operation"
Showing result 1 - 5 of 16 swedish dissertations containing the words dc drive operation.
-
1. On the design of hybrid DC-breakers consisting of a mechanical switch and semiconductor devices
Abstract : The interest of using direct current in networks for both transmission and distribution of power is increasing due to the higher efficiency compared to the alternating current used today. As no natural zero crossings exist in direct current, the interruption of fault currents becomes a challenge. READ MORE
-
2. Modular Battery Systems for Electric Vehicles based on Multilevel Inverter Topologies - Opportunities and Challenges
Abstract : 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. READ MORE
-
3. On Gate Drivers for MOS-Controlled Power Devices and dv-dt Filters for Train Traction Converters
Abstract : 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. READ MORE
-
4. Ocean Wave Energy : Underwater Substation System for Wave Energy Converters
Abstract : This thesis deals with a system for operation of directly driven offshore wave energy converters. The work that has been carried out includes laboratory testing of a permanent magnet linear generator, wave energy converter mechanical design and offshore testing, and finally design, implementation, and offshore testing of an underwater collector substation. READ MORE
-
5. Energy-efficient Generating System for HVDC Off-shore Wind Turbine
Abstract : This thesis investigates the design of energy efficient generating systems for off-shore wind turbines. For the generator part of the electric drive system, a surface mounted permanent magnet synchronous generator (SPMSG), an interior permanent magnet generator (IPMSG) as well as a synchronous reluctance generator (SynRG) have been investigated. READ MORE