Speaker
Cristina Rea
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P1.1076.pdf
The Development of First Plasma Operations on ITER
J. A. Snipes1, H. Anand1, K. Blackler1, P.C. de Vries1, J. L. Fernandez-Hernando1,
Y. Gribov1, T. C. Luce1, I. Nunes2, I. Prieto-Diaz1, L. Zabeo1
1
ITER Organization, CS 90 046, 13067 St. Paul-lez-Durance, France
2
Instituto Superior Técnico, Lisbon, Portugal
ITER construction is well underway and first plasma operations on ITER are planned at the
end of 2025. Individual plant system commissioning will begin with the Steady State
Electrical Network in late 2018 and proceed as each of the initial plant systems becomes
available up to the closure of the cryostat in late 2024. That defines the start of integrated
commissioning and final preparations for plasma operation. Operational plant system
commissioning must include commissioning with the Central Interlock System (CIS) and the
Plasma Control System (PCS) to ensure investment protection and coordinated central
control functions can be carried out. An additional Plasma Investment Protection System
(PIPS) will also need to be commissioned initially for superconducting magnet protection of
the poloidal field (PF) and central solenoid (CS) coils to avoid approaching force and field
limits. Control and investment protection diagnostic commissioning will also be carried out
as each diagnostic comes on line. The development, testing, and pre-pulse validation of
control algorithms will be carried out using the Plasma Control System Simulation Platform
(PCSSP) and similar simulation platforms for PIPS and CIS investment protection functions.
First plasma scenarios will begin in hydrogen at a toroidal field of 2.65 T with
attempts to achieve Ohmic breakdown within a limited neutral pressure range calculated to
be around 0.3 mPa < p < 0.5 mPa. At higher neutral pressures, plasmas are not expected to
reach the first plasma requirements of Ip ≥ 100 kA for at least 100 ms. If Ohmic breakdown is
unsuccessful, electron cyclotron heating will be progressively added in 0.83 MW increments
for short pulses (< 300 ms), possibly up to a total of 6.7 MW injected power. Plasma control
scenarios must be designed to ensure that the maximum plasma current does not exceed 1
MA to stay within j x B structural limits of the vacuum vessel supports to the temporary
poloidal stainless steel limiters. A backup option to improve breakdown conditions may also
be to operate at full toroidal field up to 5.3 T after full magnet commissioning.
The development of first plasma operations, initial PCS and investment protection
commissioning, initial control and investment protection algorithm development and testing,
and first plasma operation scenarios will be described.
