Sökning: "DC systems"
Visar resultat 1 - 5 av 230 avhandlingar innehållade orden DC systems.
1. DC distribution systems
Sammanfattning : .... LÄS MER
2. Accelerating Distributed Storage in Heterogeneous Settings
Sammanfattning : Heterogeneity in cloud environments is a fact of life—from workload skews and network path changes, to the diversity of server hardware components, these are all factors that impact the performance of distributed storage. In this dissertation, we identify that heterogeneity can in fact be one of the primary causes of service degradation for storage systems. LÄS MER
3. Modular Battery Systems for Electric Vehicles based on Multilevel Inverter Topologies - Opportunities and Challenges
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
4. On the design of hybrid DC-breakers consisting of a mechanical switch and semiconductor devices
Sammanfattning : 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. LÄS MER
5. Enhanced Active Resonant DC Circuit Breakers for HVDC Grids
Sammanfattning : High-voltage DC (HVDC) grids are considered promising for the electricity grid expansion required to integrate renewable energy sources into the existing infrastructure. DC fault currents increase rapidly and lack a current zero crossing. LÄS MER