The electrical aspects of the choice of former in a high T-c superconducting power cable

Centrally located in a superconducting power cable the former supplies a ri gid means onto which to wind the superconducting tapes and enables a contin uous supply of cooling power via a flow of liquid cryogen through it. There fore, the choice of former has a broad impact on the construction and desig n of a cable. The diameter of the former determines the overall diameter of the total cable, influences the heat loss to the ambient and enters into t he total AC-losses. Depending on whether the former is made of a good or po or electrical conductor eddy currents in the former itself may also contrib ute significantly to the AC-loss of the cable; the choice between an open a nd a closed former determines how and where the pressure load (pressurized coolant) has to be accommodated. In this work the electrical impact of the choice of material and diameter of the former on the AC-loss of a cable con ductor is addressed.