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The AC loss of different HTS cable types were measured in alternating magnetic fields including Conductor On Round Core (CORC) cables, stacked tape conductors and Roebel cable. The applied AC magnetic field is sinusoidal with amplitudes in the range of 5 to 400 mT and frequencies up to 0.1 Hz. The AC loss of CORC and Roebel cable was measured at 4.2 and 77 K. Inter-tape contact resistance measurements showed differences for current sharing between REBCO tapes in HTS cables.
In addition detailed method of stress-strain state modeling in CORC conductors was developed. The model is based on Finite Element Method (FEM) and extensive strain measurements on REBCO tapes. Systematic measurements on single REBCO tapes were carried out combining axial tension and torsion as well as transverse loading. The FE model takes into account temperature dependence and the elastic-plastic properties of the tape materials and includes initial processing conditions during tape manufacture up to magnet operating conditions. Furthermore a comparison of FEM simulations with CORC cable bending experiments is presented with special attention for the critical bending radius as the threshold where the tapes in the CORC become irreversibly degraded. The influence of tape inter-layer friction was also investigated. A brief overview of the results is presented.