Construction and Commissioning of the KSTAR Helium Distribution System

Abstract

The KSTAR components requiring cryogenic helium coolant for superconducting magnet operations are connected to the helium refrigeration system (HRS) through the helium distribution system (HDS), the final helium distribution station. Twenty eight cryogenic valves including 4 quench protecting valves, many sensors such as temperature sensors, pressure transmitters, and flowmeters are mounted on the system. The HDS has to control the 4.5 K supercritical helium (600 g/s) for 30 superconducting coils and their superconducting bus-lines, 55 K helium (270 g/s) pressurized to 18 bars for the thermal shields and the gravity supports, and a maximum 17.5 g/s of liquid helium for 18 current leads, provided from the HRS which has a 4.5 K equivalent cooling power of 9 kW. The helium distribution system consists of a helium distribution box (DB), 5 helium transfer lines, a PLC based helium control system (HCS), etc. The helium control system is connected to the KSTAR supervisory control & interlock system. The detailed status regarding the construction, commissioning during first cool-down, and the instrumentation & control (I&C) system are included in this paper.Index Terms-Helium distribution system (HDS), helium refrigeration system (HRS), KSTAR, superconducting magnet.

Analysis of the Helium Behavior Due to AC Losses in the KSTAR Superconducting Coils

“…The HRS provides 600 g/s of SHe for the SC coils including 300 g/s for the TF coils and 300 g/s for the PF coils. The SHe distributed by the helium distribution system (HDS) has sufficient mass flow to operate each of the SC coils [4]. Fig.…”