590 / 2017-05-15 08:32:55

Investigation of the performance of a novel mechanical HVDC circuit breaker topology

HVDC ,Circuit breaker,PSCAD,vacuum interrupter

The objective of this paper is to propose a novel topology of DC circuit breakers. The DC circuit breaker topology has a significant advantage in full-range DC current switching. Meanwhile the topology meets the demand of multiple operations required by DC system. The DC circuit breaker is based on artificial current method. When a load current or an over-load current emerges, one precharge capacitor bank is connected to the LC current injection circuit generating oscillating current. The oscillating current is injected into the DC current generating an artificial current zero, which extinguish the DC arc. However, when a short-circuit current is encountered, which would have been exceeded the amplitude of oscillating current, an additional precharge capacitor bank is connected to the LC current injection circuit. The second precharge capacitor bank is in parallel with the first one and two capacitor banks oscillating with inductor together generating a higher amplitude injection current. In this way, a short-circuit current can be interrupted with lower value of di/dt at current zero. The performance of circuit breaker is tested by PSCAD models and more simulation results will be presented in the full paper.