Cryogenic process optimization for simultaneous cool down of the TF and PF superconducting coils of SST-1 Tokamak

Recent experiments of SST-1 have shown that cryogenic heat loads are more than installed cold capacity. Due to this fact, the system cool down goes into the status-quo in temperatures at ~12K and further cool down is not possible. This issue can be resolved in three folds i.e. by grouping and distribution of the PF coils, optimization of the cryogenic plant process and heat loads reduction. First, we replaced common PF coils distribution to three groups having equal path lengths. Secondly, providing the best possible pressure heads to each PF groups during cool down and using turbine-C to get cold capacity with active cooling of all paths. Third is the heat loads reduction at some parts of SST-1. While adopting the same, it has been shown that the simultaneous cool down of the TF and PF coils are possible while achieving superconducting transition in all the coils except PF-5(lower).