Development of high Tc superconducting elements for a novel design of fault current limiter.

The operation of a superconducting fault current limiter (SFCL) relies on the increase in circuit impedance produced when a superconducting element changes from its superconducting to its normal state during a fault. In this work, composite reaction textured Bi-2212 has been modified to optimise its material properties specifically for use in a SFCL. The normal state resistivity, rho(n), and rate of change of resistivity in the flux flow region, d rho(f)/dt, are shown to be particularly important, together with the mechanical and thermal properties of the material. A single phase test SFCL has been constructed to characterise the performance of this material during simulated faults.