Upgradation plans of SST-1 Cryogenics system at IPR

10th Asia Plasma and Fusion Association Conference

Tanna, V.L.^1 ; Pradhan, S.^1

Institute for Plasma Research, Near Indira Bridge, Bhat, Gandhinagar

382 428, India^1

关键词: Central solenoid;    Engineering solutions;    Experimental campaign;    Flow optimization;    Operation pressure;    Steady state superconducting tokamak (SST-1);    Superconducting tokamak;    Support structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/823/1/012002/pdf
DOI  :  10.1088/1742-6596/823/1/012002

来源: IOP

【 摘 要 】

Steady State Superconducting Tokamak (SST-1) is India's First Superconducting Tokamak and has Toroidal Field (TF) and Poloidal Field (PF) superconducting coils along with the cold mass support structure weighing about 38 ton of cold mass. A 1.3 kW Helium refrigeration and liquefaction (HRL) at 4.5 K along with its distribution network facilitates the cooling down of the cold mass and cryo-stable operation of SST-1TF magnets. SST-1 experimental campaigns have revealed that the existing HRL is just sufficient for the heat loads acting on it. Further, the SST-1 PF magnets require a higher pressure head and mass flow rate than the nominal values on account of the longer paths of some of the PF magnets. In order to make SST-1 being fully superconducting device, we are introducing superconducting central solenoid (CS). Detailed estimates have been made and it has been found that an additional ∼ 900 W at 4.5 K of cryo power is required towards (i) cooling all the PF magnets (ii) the cooling down and the operation of a new Nb3Sn based CS of SST-1. This paper will elaborate on (i) the experimental heat loads acting on the cryo system (ii) the 'thermal runaway amongst the PF magnets observed in the SST-1 campaign' (iii) the robust need of a higher operation pressure up to 2.1 bar (a) (iv) the need of the flow optimizations as per the hydraulic paths (v) the engineering solutions at each of these described (i)-(v) above.