A Novel Bi-directional Hybrid High Voltage DC Fault Current Limiter Based on Superconducting Material and Power Electronic Devices

Compared with traditional AC transmission system, the development of DC transmission system is constrained by the amplitude limitation of fault current, since there is no natural zero crossing. This paper provides a new high voltage directional current hybrid fault current limiter topology which can be used to limit bi-directional fault current. The new hybrid fault current limiter topology uses the topology including fully-controlled electrical power switches and superconducting materials, which works together to limit the fault DC current. Superconducting material in this hybrid fault current limiter topology is being applied during the time when fault current is losing control, especially in time delay of sensing and judging the fault current by electrical power switches. As long as fault current is conformed, the part of power switches will take the rest of the works. Compared with other types of fault current limiter topologies, it provides a better fault current limitation results and at the mean time with much simpler control strategy.