Predictions of equivalent modulus of superconducting busbar

The cable body of the superconducting busbar conductor for ITER by the multistage twist of the superconductivity strand and the pure copper strand is quite soft. How to process it affects the equivalent prediction of the entire conductor performance. According to the traditional composite theory, the following several predictions were carried: only consider the functions of the stainless steel conduit outside the cable body, the double insulation and the double shielding layer; the influence of the flexible cable body is neglect, so only consider the function of its internal helium tube; the material nature of the cable body is assumed the isotropism, which the elasticity modulus is 1-10 GPa (here taking 2 GPa); combining the homogenization theory with the composite damage theory. Finally, the equivalent elasticity modulus and the reference experimental moduli were compared. The result of the last prediction is relatively reasonable and the influence of the cable body to the superconducting busbar conductor is very small. (authors)