1. Poster ID: FIP/P7-26: Preventive measures to avoid electrical arcing incidences in SST-1 PF current leads
As a preventive measure to mitigate arcing inside CFS chamber, insulation strengthening processes have been initiated to increase the voltage withstand capability of the SST-1 PF current leads.
An insulation scheme using polyimide and GFRP along with Bisphenol-A based epoxy resin has been developed at lab scale.
Electrical characterization involves insulation resistance (IR) measurement, tan delta measurement (dissipation factor test), thermal cycles (subjecting insulation to thermal shock from room temperature to 80 K) and breakdown voltage measurement. A breakdown voltage of > 25 kV DC has been successfully achieved with ~1.2 mm of insulation thickness at lab scale insulation samples at room temperature (RT).
In order to validate the proposed insulation system for SST-1 PF current leads under low temperature and helium environment, a test setup has been developed, fabricated and assembled. During the testing of dummy current leads in the helium Paschen condition, the leakage current of the insulation will be measured at different applied voltages.
Vacuum and room temperature testing of the dummy current lead insulation samples have been tested at 5 kV DC. Further testing at low temperature and under helium gas environment to simulate Paschen condition has been initiated.