A novel topology of bridge-type superconducting fault current limiter

A new topology of bridge-type SFCL, which can limit not only the rising speed but also the steady state value of fault current, is proposed in this paper. The new SFCL includes a bridge composed of 4 SCRs and 2 diodes, a superconducting coil and an ordinary bypass reactor. In normal status, the bridge works as a rectifier, the voltage across the coil is zero if the current of the coil keeps greater than the peak value of the load current. When a fault occurs, the fault current is limited in the first cycle by the coil, when the fault is detected, the bridge can be controlled working as two bidirectional switches and the coil is inserted in the ac circuit and the steady fault current can also be limited. By adding the bypass reactor, the cost of the new SFCL can be minimized. Parameter design and simulations are presented. The simulation proves the validity of the new SFCL.