AC loss of a high-T-c superconducting power-cable conductor

We investigate the AC loss of a high-T-c superconducting power-cable conductor with four layers and interlayer insulation. The electric-circuit model is applied for the calculation of the AC loss of the conductor. The result of a calculation for the BC loss shows that the calculated value is nearly equal to the experimental value; therefore this model explains the electromagnetic properly of the conductor well. Moreover the result of a calculation for the current distribution of the conductor indicates that almost all the current passes through the outer layer when the transport current is less than the I-c of the conductor. Finally we calculate the relation between AC loss and the spiral pitch of the high-T-c superconducting wires which make up the conductor. It is found that the AC loss is markedly decreased when the spiral pitch is less than 0.5 m.