Sökning: "AC DC system"
Visar resultat 1 - 5 av 83 avhandlingar innehållade orden AC DC system.
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. On Techno-economic Assessment of a Multi-terminal VSC-HVDC in AC Transmission Systems
Sammanfattning : The Voltage Source Converter based Multi-Terminal high voltage Direct Current transmission system (VSC-MTDC) is currently considered as an attractive technical option for increased transmission capacity and improved controllability and flexibility of an electric power grid, thanks to its unique performance characteristics, and the possibility of using the extruded XLPE cables. In the planning process of embedding a VSC-MTDC system into an ac transmission grid, one must assess the potential values in terms of improved energy efficiency, i. LÄS MER
3. Operation and control of HVDC links embedded in AC systems
Sammanfattning : .... LÄS MER
4. Coordinated Frequency Control Between Interconnected AC/DC Systems
Sammanfattning : With ambitions of reducing the environmental pollution, power systems integrate larger shares of Renewable Energy Sources (RES) to phase out conventional thermal and nuclear generators. Since RES (such as wind and solar power) are connected to the grid through power electronics devices, they do not inherently contribute to system inertia. LÄS MER
5. On Stability Enhancement in AC/DC Power Systems through Multi-terminal HVDC Controllers
Sammanfattning : Due to the increasing share of renewable energy sources in modern power systems and electricity market deregulation, heavy inter-regional and cross-border power flows are becoming a commonplace in system operation. Moreover, large-scale integration of renewable energy sources is expected to pace up, therefore new solutions have to be developed to integrate these intermittent sources, which are also characterized by being distributed over large geographical areas, such as offshore wind farms. LÄS MER