Irregular Flux Linkage for Coupling Current Loops in Different Type CIC Conductors

Coupling current losses in large scale cable-in-conduit conductors (CICCs) for fusion apparatuses are sometimes annoyance because nobody can estimate how large the coupling loss is before fabricating hundred-meters of long conductor. Our approach for analyzing and estimating the loss based on real strand traces is unique compared with that of other research groups. In process of this approach, we have already measured the traces in two types of CICCs, one has circular cross section and the other has rectangular one. The cabling pattern of the former is 3⁴ = 81 the latter is 3⁴ times 6 = 486. The flux linkage area in a coupling current loop which consists of two contacting strands is evaluated as an indicator of driving force of the coupling current, which is proportional to the square root of AC loss per unit time. The flux linkage areas showed that the losses of rectangular-shape CICC would be larger than that of circular-shape CICC.