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arXiv · 2101.01754

Blocks-in-Conduit: REBCO cable for a 20T@20K toroid for compact fusion tokamaks

Peter M McIntyre·John S Rogers·Akhdiyor Sattarov
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Abstract

Blocks-in-Conduit is a novel approach to cable, coil, and splice technologies with unique benefits for a high-current-den-sity toroid D winding to operate at 20 T, 20 K. Blocks of REBCO tape are cabled in conduit, with a thin-wall center-tube spring that provides transposition, stress management at the cable level, and cross-flow cooling of a thick-coil toroid winding. The coil technology utilizes a co-wound armor structure that integrates stress manage-ment and cross-flow cooling and bypasses coil stress to protect the BIC. An interleaved splice joint enables low-resistance demountable splices of the windings. These provisions yield maximum current density in the winding pack, maximum stability of the REBCO tape blocks, and minimum conductor cost for a tokamak toroid.

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Peter M McIntyre, John S Rogers, Akhdiyor Sattarov. 2021-01-05. Blocks-in-Conduit: REBCO cable for a 20T@20K toroid for compact fusion tokamaks. https://doi.org/10.1109/tasc.2021.3064518

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