RAMP RATE EXPERIMENTS ON A NB3SN CICC WIND-AND-REACT MAGNET

The Central Solenoid of ITER is designed to operate at 13T, 0.5-1 T/s, 5.8K. There is an experimental evidence that reduced performances in variable field, not explained by BC loss, could occur in CIC conductor s. Such ramp rate limitations have to be well understood in order to b e avoided in the ITER conductors. The ENEA Nb3Sn solenoid is a Im OD, 0.6 m ID coil, made of a CIC conductor which is a factor 8 smaller tha n the ITER full size cable. The total conductor length, 750m, is ITER relevant. An experimental setup has been assembled, allowing ramp rate and DC tests on the ENEA coil up to 8T, 2-4T/s, 12K. Main objectives of the program are experimental data on ramp rate limitation, pulsed c urrent distribution in the s/c cable, limiting currents and global AC loss. This paper reports the results of the measurements carried out u p to now.