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Description
This research explored thermal and electrical sharing, as well as quench, in the cable/composite winding cross-section of an epoxy-impregnated HEP dipole accelerator magnet using HTS（ReBCO）Cables. While HTS insert designs can vary, and in some cases, either no insulation tape windings or fully cooled cable windings are being contemplated, this design is for cables with indirect cooling (epoxy impregnation) with specified electrical and thermal inter-cable resistances. The cables also have a defined level of defects within them, both in terms of severity and density. A direct simulation of the magnet winding with full detail in the cable structures would be far too computationally expensive to give sensible run times. However, our approach was to use results from previous modeling runs on cables to develop simple cable proxies which replicated the main results of the cable properties (Temperature and voltage distribution at a given current), but were averaged over length scales smaller than the cable length scale, but larger than that of the tape. These proxies were then used to construct a magnet winding cross-section, where inter-cable electrical and thermal interlayer values could be specified. Due to the complexity of the structure, we used Modelica to guide the research direction which is coarser but faster. For the present study, the magnet was designed with nine cables in each of the four quadrants, and one quadrant was studied. The cables themselves were constructed from thirty tapes each. The tendency for quench as a function of current was explored, and compared to the performance of the isolated cables.
