DC current interruption in HVDC SF/sub 6/ gas MRTB by means of self-excited oscillation superimposition

HVDC Circuit Breakers: A Review Identifying Future Research Needs

“…The total breaker can consist of one single unit [52] or be the series connection of several individual ones with lower voltage rating [61], [62]. The interrupter in the nominal path can be an oil breaker [60], air-blast breaker [62], vacuum interrupter [63]- [65], or an SF6 gas circuit breaker [50], [61], [66]. Breakers where the inductance L c of the commutation path is a separate coil [62] or uses the stray inductance of the path [61] have both been proposed.…”

“…The AC circuit breakers that are typically used as elements in the nominal path are by no means optimized for this. Thus, dedicated investigations studying the arc characteristics under different conditions have been performed [50], [72], [73] and it was even tried to optimize the breaker [66]. Nonetheless, as the classical configuration with only passive elements is probably the most economic and most reliable one, further investigation of the arc behavior under different conditions to optimize the breaker is surely needed.…”

Five years of pulsed current testing for HVDC switchgear

“…The considerable current gradients of up to 50kA/ms lead to extensive voltage drops along any inductance in series with the load 4 . Initially, FPDCS was located in a separate room, some distance away from the devices under test and connected through bus bars of 12µH.…”

“…However, in research and development tests of CB components, significantly higher current gradients have to produced, particularly when evaluating resonance performance and arc characteristics (cf. [3], [4]). For this very reason, an initial plan for building a current source capable of delivering current pulses at a maximum amplitude of 20 kA at gradients of up to 200 kA/ms was presented in 2010 by Walter (cf.…”

Condition Assessment of Passive MRTB Based on Fuzzy Theory

“…AND YET these researches have made a magnificent contribution in improving the safety and stability of HVDC CBs. However, applying of HVDC CBs is impeded by the discoordination of commutation path ,nominal current path and energy absorption path [6]. This paper, on the background of a 500kV convert station, proposes an online condition assessing method and devises a corresponding device.…”