The US is responsible for 88% of the ion cyclotron transmission lines, including research and development (with Oak Ridge National Laboratory and Princeton Plasma Physics Laboratory), design, fabrication, and interfaces. The ITER Organization is responsible for installing the ion cyclotron transmission lines (12%).
The ion cyclotron system heats the ions in the plasma with a high-intensity beam of electromagnetic radiation. Generators produce high-power radio frequency waves that are carried along multiple transmission lines to antennas located in the vacuum vessel, sending the waves into the plasma. The US ion cyclotron transmission lines will provide efficient power transfer from 40–55MHz radio frequency sources to the plasma heating antennas.
The system will include coaxial transmission lines and a matching/tuning system to minimize power transfer losses. The pressurized lines can transmit up to 6 MW per line. In total, approximately 1.5 km of line connects 8 sources to 16 antenna feeds, with 14 types of transmission line and matching system components. The main interfaces include sources, launchers, buildings, port cells, and water cooling. The short coaxial line also provides secondary tritium confinement.
For more information, contact: Ben Hardy, IC Transmission Lines Team Leader, US ITER Project Office, Oak Ridge National Laboratory, hardybl@ornl.gov | 281-740-1996.
The I&C team has completed a number of design achievements in preparation of First Plasma deliveries, including: Ion Cyclotron Heating (RF Bldg.) I&C First Plasma Final Design Review (December 2017), Tokamak Cooling Water System I&C First Plasma Final Design Review (November 2017), Vacuum Auxiliary System (03) Conceptual Design Review (July 2017) and Roughing Pumps System I&C Conceptual Design Review (April 2017).
To provide initial heating for fusion reactions, a combination of high-powered heating systems will be installed for the international ITER tokamak, including radio frequency (RF) transmission lines that will deliver 20 million watts of power to the plasma. For perspective, that’s about 400 times more power than a large radio station uses for transmission. The US ITER ion cyclotron team at Oak Ridge National Laboratory has achieved high RF power levels in the laboratory and is working to finalize the design of the transmission lines and matching systems.
US ITER researchers at the University of Wisconsin and Oak Ridge National Laboratory are developing advanced processes to assess ITER’s unique tokamak components and materials in the presence of the tremendous amount of neutron flux and energy released by fusion reactions. The process, called neutronics analysis, involves a palette of complex computational codes and libraries for predicting neutron impacts.
