학술논문

4.5 K Paschen Qualification Testing of Terminal Joint and Voltage Tap Insulation Designs for ITER CS Module Test Facility
Document Type
Periodical
Source
IEEE Transactions on Applied Superconductivity IEEE Trans. Appl. Supercond. Applied Superconductivity, IEEE Transactions on. 34(5):1-4 Aug, 2024
Subject
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Wires
Testing
Insulation
Polyimides
Voltage
Test facilities
High-voltage techniques
Central Solenoid
ITER project
magnet testing
Paschen
superconducting
Language
ISSN
1051-8223
1558-2515
2378-7074
Abstract
General Atomics (GA) is fabricating seven ITER Central Solenoid Modules (CSM) for the ITER Organization (IO). As part of the fabrication process, all CSMs undergo factory acceptance testing (FAT) prior to shipment to the IO. The FAT includes charging the modules to 40 kA and performing fast discharges (7.3 second decay time constant) to measure alternating current (AC) losses. These fast discharges generate high voltages at the electrical connections between the CSM and the test facility. Due to a fast discharge fault during the CSM 3 FAT, Paschenization methods of high voltage connections between the CSM and the test facility needed to be developed, qualified, and implemented. These connections included the coaxial and twinbox joints, all in-chamber instrumentation voltage tap wire splices, and voltage tap chamber feedthroughs. A test article was manufactured to replicate these connections and joints, and qualify the locally removable Paschenized insulation designs with a Paschen Test at 4.5 K. The 4.5 K Paschen test was comprised of 15 kV tests between 1E-03 and 1 mbar. This paper will present and discuss the Paschenization methods, lessons learned from research, and the CSM implementation in the test facility.