Commissioning and Operation of ITER CS Module Test Facility: DC Power Supply and DC Breaker Systems

Two systems used in factory acceptance power testing of the ITER Central Solenoid Module (CSM) at General Atomics’ Magnet Technologies Center are the Alpha Scientific 50 kA dc power supply (DCPS) and the Siemens 50 kA dc circuit breaker (DCB). Both systems were designed specifically for this application; capable of charging the CSM to 50 kA and safely discharging its stored energy, up to 1GJ. Nominally the DCPS and DCB would have been fully commissioned after completion of CSM1 testing. However, several issues occurred during the first three test campaigns, precluding completion of the full power test plan. This paper discusses these issues, their investigations, and upgrades implemented to both the DCPS and DCB; including the design and build of a superconducting inductor (SCL) used as a test load to debug the DCPS. All of which culminated in successful completion of CSM4 power testing, verifying the commissioning of both these systems.