R. H. Goulding , M. Carter , P. Ryan ,
D. Swain , F. W. Baity , D. B. Batchelor ,
E. F. Jaeger
Oak Ridge National Laboratory, Oak Ridge, TN, US
R. Majeski and J. R. Wilson
Princeton Plasma Physics Laboratory, Princeton, NJ, US
G. Bosia
ITER Joint Central Team, Garching, Germany
Abstract
Advanced physics scenarios need radiofrequency (rf) systems to heat
either ions or electrons, to drive current at the center of high density
discharges, to control plasma conditions by manipulation of the heating and
current profiles, and possibly to establish rf-driven transport
barriers. Operationally, the systems must deliver high power into rapidly
varying plasma loads, with good performance over a wide range of plasma
density and magnetic field strengths, and both high reliability and efficient
use of installed power capability. Other important features are high power
density to decrease port space, long-pulse or steady state operation, and
compatibility with a reactor environment. Two programs in which ORNL is
helping to advance the level of rf system development are the ICRF antenna
design for ITER and the high harmonic fast wave (HHFW) antenna array for
NSTX . The ITER antenna array is designed to heat both ions and electrons and
to drive current over a frequency range of 40-70 MHz. An ITER prototype
antenna has been fabricated and is undergoing vacuum testing at
ORNL. Initial test results are presented. The NSTX HHFW 12-strap array has
been designed to launch a highly directional wave spectrum for
non-inductive current drive . We report on the antenna and feed system
design, measurements
on a mockup antenna, and physics modeling used in the design process.
IAEA 1999