Vapour cooled current leads-operations and control for Nb₃ Sn coil test

Current leads are essential components to power the superconducting magnets from room temperature 300 K power supply end to 4.5 K terminals of superconducting magnets. At IPR, recently we have carried out Nb₃ Sn superconducting coil test and validation using indigenously developed 10 kA rated vapour cooled current leads (VCCLs). These VCCLs are operated reliably in different scenario such as initial cooldown, electric current (ramp up, ramp down and log time steady state condition), cold with no current and quench etc. A dedicated 12 kA / 16 V Switch Mode Power Supply (SMPS) was used to power the superconducting magnet via current leads. One pair of VCCLs are used to test Nb₃Sn proto type coil. This paper describes operation and control of VCCLs for Nb₃ Sn coil test with results obtained during the experiment.