Title :
Test Results of a 100 kA NbTi CICC
Author :
Bruzzone, P. ; Stepanov, B. ; Wesche, R. ; Calvi, M.
Author_Institution :
CRPP, Fusion Technol., EPFL, Villigen, Switzerland
fDate :
6/1/2012 12:00:00 AM
Abstract :
For the secondary winding of the flux pump (super- conducting transformer) of the EDIPO test facility at CRPP Villigen, a NbTi cable-in-conduit conductor (CICC) was designed at CRPP and procured at the industry. From a left section of the CICC a SULTAN sample, nicknamed TRASEK, has been assembled and tested. In the conductor design, high Cu:non-Cu ratio in the strand (no copper segregation), low void fraction and SnAg5 coating of the strand surface are selected to allow smooth current redistribution and enhance the take-off voltage. The DC tests are carried out be- fore and after solder filling the sample termination and current sharing is observed up to 80 kA. Eventually, the DC conductor performance is limited by the self field of the sample in the U-bend region. In normal operation, the secondary coil of the transformer is not exposed to significant magnetic field sweeps. The AC loss is expected to be large according to the design choices (tin coating, low void fraction). The AC loss characterization in SULTAN includes over 400 load cycles. The pressure drop vs. mass flow rate is measured in SULTAN to complement the data base for friction factor of CICC´s.
Keywords :
magnetic fields; niobium alloys; silver alloys; superconducting cables; superconducting transformers; tin alloys; titanium alloys; transformer windings; AC loss characterization; CICC; CRPP Villigen; DC conductor performance; DC tests; EDIPO test facility; NbTi; SULTAN sample; SnAg; TRASEK; U-bend region; cable-in-conduit conductor; conductor design; copper segregation; current 100 kA; current sharing; flux pump; magnetic field sweeps; mass flow rate; pressure drop; sample termination; secondary coil; secondary winding; smooth current redistribution; solder filling; strand surface; superconducting transformer; take-off voltage; test results; void fraction; Cable shielding; Conductors; Copper; Helium; Resistance; Superconducting cables; Windings; Cryogenics; data processing; superconducting cables; test facilities; testing;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2011.2174597