Search

The activities in Europe towards the development of the EC power sources for ITER are centered on the development of a 170GHz, 2MW, CW coaxial cavity gyrotron of collector potential depressed (CPD) type. A gyrotron with a higher unit power than the ITER reference (I MW) would yield a reduction of the installation costs, a more compact launcher design and, if required, an increase of the power delivered through one port. Tests proving the principle were successfully performed on a short-pulse experimental gyrotron delivering up to 2.2 MW in single mode. Following this success, a coordinated and fully consistent programme of development has been launched. The first industrial 2 MW prototype is now at an advanced stage of construction. The associated superconductive magnet producing 6.86 T on the cavity axis is also being procured. Dummy loads suitable for short and CW operation are also part of the development effort. Finally, a new EC test facility, with the features necessary for the testing of the gyrotron up to full power in CW, has been established and includes a fully solid-state power supply system. (c) 2007 Published by Elsevier B.V.

The EU will be providing the largest contribution to the ITER electron cyclotron (EC) heating and current drive (H&CD) system (20 MW, CW at 170 GHz). The contribution includes one third of the H&CD gyrotrons, their associated power supplies and four upper port launcher antennas. In all areas of participation, the EU EC partnership (coordinated by the European Fusion Development Agreement) aims toward advancing the technology, while staying within a specified cost envelope. This is portrayed in the co-axial gyrotron development that offers the potential to double the output power per source (2.0 MW), increasing the delivered power for a fixed number of auxiliary systems. The EU partnerships also attempt to increase performance for the entire EC system, in particular the launching antennas. The proposed front steering launcher design offers greater control of MHD activity than the previous remote steering design and opens up the possibility of an enhanced performance UL. The EC physics requirements are repartitioned between the upper and equatorial launchers for a synergetic balance, which increases the EC physics capabilities while relaxing some of the engineering requirements. (c) 2007 Elsevier B.V. All rights reserved.