Applications of DC Breakers and Concepts for Superconducting Fault-Current Limiter for a DC Distribution Network.

Many alternative energy power generation systems create dc electricity. Also, many devices consume dc converted from ac. Therefore, it may be possible to reduce conversion losses and CO[sub2] emissions by adopting dc distribution. We assume that superconducting cables will be used for dc distribution because their electrical resistance is almost zero. However, if a superconducting cable is adopted, it is of great concern that if an excessive current flows because of, for instance, a short circuit, then there is a possibility that this current cannot be interrupted by a circuit breaker alone. We propose that the fault current be limited by a superconducting fault-current limiter (SFCL) and that this limited current is then interrupted by a dc circuit breaker. In this paper, we have separately investigated the SFCL and dc breaker and their use in combination. [ABSTRACT FROM AUTHOR]