Speaker
Mireille Schneider
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/I4.010.pdf
Heating and Current Drive systems in the ITER research plan
M. Schneider, D. Boilson, M. Henderson, S.-H. Kim, P. Lamalle, A. Loarte, A. Polevoi
ITER Organization, Route de Vinon / Verdon, CS 90 046, 13067 St Paul-lez-Durance, France
Reaching ITER’s mission goals of exploring burning plasma physics and achieving high
fusion gain will depend on the efficiency and robustness of its ancillary heating and current
drive (H&CD) systems for a routine access to high performance plasmas. In view of the
many roles foreseen for the H&CD systems, ITER's baseline capability consists of neutral
beam injection (NBI), electron cyclotron heating (ECH) and ion cyclotron resonance heating
(ICRH). Their complementary capabilities will address the challenges anticipated in
establishing and sustaining burning plasmas with high fusion power for various operating
scenarios. This flexibility will also be key to the development of scenarios in hydrogen and
helium plasmas during the pre-fusion power operation phase. High power heating is essential
to ensure H-mode access for high fusion gain, relying on the most advanced built to date
systems, utilizing several aspects of novel technology. They must ensure routine stationary or
modulated operation for 3600 s to support the development of long-pulse plasmas,
particularly in predominantly non-inductive operation.
NBI will deliver 33 MW through vertically steerable beamlines to provide radial variation of
H&CD profiles. It is the main source of bulk current drive in ITER. As in most fusion
devices, the main operational constraint is the plasma density, which must be sufficiently
high to prevent excessive ‘shinethrough’ heat loads on in-vessel components. ECH system
can launch 20 MW via a single equatorial launcher combining co- and counter-current
injection, or through 4 upper ports, enabling plasma breakdown EC-assist, MHD control,
current profile shaping and core tungsten control. Its local H&CD deposition over a
substantial radial range provides high flexibility for both inductive and non-inductive
scenarios. ICRH antennas will deliver 20 MW providing high flexibility ion and electron
heating, through the appropriate choice of frequency and heating scheme to support scenarios
over a significant range in toroidal field, current, density and fuel species. They also provide
sawtooth and core tungsten control capabilities. Outstanding issues are related to ITER edge
plasma profiles that influence coupling efficiency and RF sheath effects.
This paper will discuss recent developments of the ITER project and specific roles of ITER
H&CD systems in meeting the challenges associated with the successful implementation of
the ITER Research Plan, making use of physics modelling and supporting experiments to
evaluate their expected performance in ITER. Options available to the ITER project for
longer term upgrades of the H&CD systems will also be discussed.
