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High temperature superconducting current leads (HTS-CL) are designed to supply the current to the large superconducting ITER magnets for the operation with reduced heat load to the cryogenic system. The Toroidal field (TF) current leads are the largest with a current capacity of 68 kA each. The Institute of Plasma Physics of the Chinese Academy of Sciences (ASIPP) is responsible for the supply of the current leads based on a design jointly developed with the ITER organization. Before the supply of the TF HTS-CL series, a pair of prototypes was manufactured in 2014 by ASIPP and associated manufacturers according to previously qualified manufacturing procedures. Rigorous quality control measures were developed and applied in preparation for series manufacturing. To verify compliance of the prototypes with the ITER specification, thorough testing was conducted in 2015. The test items under particular scrutiny were: the pressure drop in the counter-flow heat exchanger, the loss of flow accident test after steady state operation at 68 kA current, the so-called overheating time of the HTS module following an induced quench, the electrical resistances of the soldered joints inside the lead assembly (i.e., the low temperature superconducting (LTS) to busbar and the HTS to LTS joints), and the conduction heat load per lead to the 4.5  K end. In this paper, the main manufacturing steps are discussed, and test results are presented and discussed. [ABSTRACT FROM AUTHOR]

To carry current for the ITER correction coils, the 10-kA high-temperature superconducting current leads studied here are designed. Current leads provide the transition from 4.5-K low temperature to room temperature. This paper summarizes the major design features of the prototypes, which is followed by a discussion of the manufacturing and testing. The test results approved their excellent performance on low joint resistance and long loss-of-flow accident time. The overheating time, mass flow, and heat loads to 5-K ends also reached the expectation. [ABSTRACT FROM AUTHOR]

ASIPP will supply for ITER all the current leads. There are three types of high temperature superconducting (HTS) current leads designed to carry 68 kA, 55 kA, or 10 kA to the ITER magnets. Different from the trial leads manufactured and tested in Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), some critical technologies were qualified before the manufacturing of the ITER leads could commence, including: 1) welding, brazing, and soldering qualification; 2) fin type heat exchanger (HEX) with tight assembly tolerance; 3) low temperature superconducting (LTS) linker with cables soldered to the 5 K copper terminal; 4) instrumentation mock-up for the temperature and voltage test. In this paper, the outcome of these qualification activities will be reported together with the plans for the series production planning and development. [ABSTRACT FROM PUBLISHER]