Process optimization of helium cryo plant operation for SST-1 superconducting magnet system

26th International Cryogenic Engineering Conference & International Cryogenic Materials Conference 2016

材料科学;物理学

Panchal, P.^1 ; Panchal, R.^1 ; Patel, R.^1 ; Mahesuriya, G.^1 ; Sonara, D.^1 ; Srikanth, G.L.N.^1 ; Garg, A.^1 ; Christian, D.^1 ; Bairagi, N.^1 ; Sharma, R.^1 ; Patel, K.^1 ; Shah, P.^1 ; Nimavat, H.^1 ; Purwar, G.^1 ; Patel, J.^1 ; Tanna, V.^1 ; Pradhan, S.^1

Institute for Plasma Research, Bhat, Gandhinagar

Gujarat

382 428, India^1

关键词: Distribution systems;    Inlet pressures;    Inlet temperature;    Lower temperatures;    Plant operations;    Plasma discharge;    Stable operation;    Steady state superconducting tokamak (SST-1);   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/171/1/012024/pdf
DOI  :  10.1088/1757-899X/171/1/012024

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Several plasma discharge campaigns have been carried out in steady state superconducting tokamak (SST-1). SST-1 has toroidal field (TF) and poloidal field (PF) superconducting magnet system (SCMS). The TF coils system is cooled to 4.5 - 4.8 K at 1.5 - 1.7 bar(a) under two phase flow condition using 1.3 kW helium cryo plant. Experience revealed that the PF coils demand higher pressure heads even at lower temperatures in comparison to TF coils because of its longer hydraulic path lengths. Thermal run away are observed within PF coils because of single common control valve for all PF coils in distribution system having non-uniform lengths. Thus it is routine practice to stop the cooling of PF path and continue only TF cooling at SCMS inlet temperature of ∼ 14 K. In order to achieve uniform cool down, different control logic is adopted to make cryo stable system. In adopted control logic, the SCMS are cooled down to 80 K at constant inlet pressure of 9 bar(a). After authorization of turbine A/B, the SCMS inlet pressure is gradually controlled by refrigeration J-T valve to achieve stable operation window for cryo system. This paper presents process optimization for cryo plant operation for SST-1 SCMS.