Critical Current Measurement of REBCO Cables by Using a Superconducting Transformer

TL;DR

This paper reports on the critical current measurements of REBCO cables using a superconducting transformer, highlighting the effects of magnetic field and cable construction on performance.

Contribution

It introduces a novel measurement method for REBCO cables using a superconducting transformer, providing detailed analysis of different cable configurations under high magnetic fields.

Findings

Critical currents depend on magnetic field and cable configuration.

The superconducting transformer enables high-current measurements up to 45 kA.

Differences observed between simple-stacked and CORC cable performances.

Abstract

Development of REBCO cables that carry high electrical current in high magnetic field is crucial for future large-scale magnet applications. This experimental work presents the critical current measurements of two different REBCO cables by a test facility at the National High Magnetic Field Laboratory (NHMFL). The simple-stacked cable is made by the NHMFL by stacking 21 REBCO tapes without soldering. The Conductor-on-Round-Core (CORC) cable provided by Advanced Conductor Technologies has 21 layers of REBCO tapes with 2 tapes/layer. The test facility consists of a 12 T split solenoid magnet with 15 cm bore providing transverse field to the samples, a superconducting transformer (SCT) as a current source providing up to 45 kA current. Special attentions were paid to fabrication of solder joints between REBCO cables and the SCT output. The voltage-current traces were measured as a function of magnetic field at 4.2 K, from which the critical currents are determined. The details of this measurement are discussed.