Analysis of the ITER central solenoid insert (CSI) coil stability tests

作者：Savoldi L^*; Bonifetto R; Breschi M; Isono T; Martovetsky N; Ozeki H; Zanino R

来源：Cryogenics, 2017, 85: 8-14.

DOI：10.1016/j.cryogenics.2017.05.001

• ITER
• Nuclear fusion
• Stability
• Superconducting magnets
• Thermal-hydraulics

At the end of the test campaign of the ITER Central Solenoid Insert (CSI) coil in 2015, after 16,000 electromagnetic (EM) cycles, some tests were devoted to the study of the conductor stability, through the measurement of the Minimum Quench Energy (MQE). The tests were performed by means of an inductive heater (IH), located in the high-field region of the CSI and wrapped around the conductor. The calorimetric calibration of the IH is presented here, aimed at assessing the energy deposited in the conductor for different values of the IH electrical operating conditions. The MQE of the conductor of the ITER CS module 3L can be estimated as similar to 200 +/- 20%, deposited on the whole conductor on a length of similar to 10 cm (the IH length) in similar to 40 ms, at current and magnetic field conditions relevant for the ITER CS operation. The repartition of the energy deposited in the conductor under the IH is computed to be similar to 10% in the cable and 90% in the jacket by means of a 3D Finite Elements EM model. It is shown how this repartition implies that the bundle (cable + helium) heat capacity is fully available for stability on the time scale of the tested disturbances. This repartition is used in input to the thermal-hydraulic analysis performed with the 4C code, to assess the capability of the model to accurately reproduce the stability threshold of the conductor. The MQE computed by the code for this disturbance is in good agreement with the measured value, with an underestimation within 15% of the experimental value.

• 出版日期2017-7