US PERSPECTIVE ON THE ITER MAGNETICS R&D PROGRAM

The ITER magnetic systems will be unprecedented in size and in reliability requirements. An international R&D program is being planned for the next six years, to prepare for a decision to construct the device. The conductors will use an internally cooled cabled approach, using A-15 conductors in the toroidal field coils, and in major portions, if not all, of the poloidal field coil system. It is planned to support two approaches to Nb3Sn production, and to give parallel consideration to NbAl and other advanced strands. Several approaches to conductor jackets will be considered, both circular and rectangular, with alternative methods of fabrication and alternative materials. The selected conductors will be incorporated into significant scale model coils and tested in one or more common test facilities. Development of connectors, leads, and quench protection systems will be important parallel activities. The on-site construction and test of full-scale prototypes is anticipated to follow the initial six-year R&D program.