Sökning: "DC circuit breakers"

Hittade 5 avhandlingar innehållade orden DC circuit breakers.

  1. 1. Enhanced Active Resonant DC Circuit Breakers for HVDC Grids

    Författare :Tim Augustin; Hans-Peter Nee; Marley Becerra; Jürgen Biela; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Active damping; Actuator; DC circuit breakers; DC grid; DC power systems; Fast mechanical switch; Fault handling strategy; Gas discharge devices; HVDC; HVDC circuit breakers; Multilevel converters; Multiterminal HVDC; Power transmission; Spark gaps; Thomson-coil actuator; Vacuum interrupter; Voltage Source Converter VSC ; Electrical Engineering; Elektro- och systemteknik;

    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

  3. 2. On the design of hybrid DC-breakers consisting of a mechanical switch and semiconductor devices

    Författare :Jesper Magnusson; Göran Engdahl; Staffan Norrga; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DC; circuit breaker; hybrid breaker; DC systems; DC; brytare; hybridbrytare; likström;

    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

  4. 3. Studies on Current Commutation in Hybrid DC-breakers

    Författare :Jesper Magnusson; Göran Engdahl; Magne Runde; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Commutation; Hybrid DC-breakers; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Compared to conventional AC-circuit breakers, a DC-breaker has to act fast and force the current down to zero. Many different DC-breaker topologies are available, and this thesis is focused on the hybrid DC-breaker comprising a mechanical switch and high power semiconductors. LÄS MER

  5. 4. Ultra-fast electromechanical commutation switch for hybrid breakers

    Författare :Mrunal Parekh; Marley Becerra Garcia; Christian Franck; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : In a power system with the ability to integrate geographically spread diverse renewable energy sources, there is a need for efficient control of the power flow and effective power transmission. Power electronics can provide this controllability, at the expense of conductive losses in the used components. LÄS MER

  7. 5. Multi-terminal HVDC protections based on transient line modeling

    Författare :Niclas Johannesson; Staffan Norrga; Hans-Peter Nee; Jef Berteen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC transmission; HVDC protection; traveling wave protection; MTDC protection; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : High voltage direct current (HVDC) is considered one of the critical technologies required for the power system to enable the transition toward renewables. With an increasing geographical density of HVDC converters, there is a potential for optimization by connecting more than two converters into a shared DC transmission system, thus forming a multi-terminal HVDC (MTDC) system. LÄS MER