The Development of a HVDC SF6 Breaker

HVDC Circuit Breakers: A Review Identifying Future Research Needs

“…An alternative to the self-excited growing oscillations with purely passive components in the commutation path is the use of additional active components, like the closing switch S c . If the capacitor C c is pre-charged, a current is injected into the nominal path upon closing of S c and a counter-current is induced [61].…”

“…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].…”

“…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. If the capacitor in the commutation path is precharged, it can be inserted with a spark-gap [67], [68] or a closing switch [52], [69].…”

“…The capacitor can be charged with a dedicated charging unit with isolation switch or directly from the line [52], [69]. The energy absorption can be realized by linear or non-linear resistors [55] or non-linear ZnO surge arrestors [61], [62]. From the combination of these possible configurations, numerous breakers have been proposed and a few have been realized.…”

Topological analysis of HVDC circuit breaker with coupling transformer

“…The study on mechanical HVDC circuit breaker was carried out earlier by foreign companies and research institutions, and has successfully realized the transformation from theory design to engineering practice [11], [12]. Although mechanical HVDC breaker has the advantage of low loss and inexpensive, but its breaking current capacity is limited, the breaking time is too long to reach tens of milliseconds, which can't meet the needs of disconnecting fault current quickly in DC grid [13].…”