Sökning: "Multiterminal DC Systems"
Hittade 4 avhandlingar innehållade orden Multiterminal DC Systems.
1. 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
2. Efficient Modeling of Modular Multilevel Converters for HVDC Transmission Systems
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
3. Protection for Multiterminal HVDC Grids - A Digital Contribution
Sammanfattning : The aim of this thesis is to (1) enhance understanding of mechanisms that are important for the protection of high-voltage direct-current (HVDC) grids, and (2) suggest possible technical solutions. To that end, digital technologies were used both in simulation, as well as in a laboratory environment. LÄS MER
4. Analysis of VSC-based HVDC systems
Sammanfattning : The main objective of this thesis is to perform stability and control studies in the area of VSC-HVDC systems. A major part of the investigation focuses on the development of procedures, whose aim is to understand, explain and avoid poorly-damped conditions or instability that may appear due to dc-side resonances, which stem from the interaction of converters and passive elements in such systems. LÄS MER