Major MAST Developments
A new antenna was installed in August 2002. This will provide the first
EBW (Electron Bernstein Wave) heating and current drive studies in an
ST.
The present M3b MAST campaign began in October 2002, and features investigations
of EBW physics. When the campaign ends, a major engineering break is planned,
during which key upgrades will be made to the MAST facility. These include:
- A Replacement centre stack giving 37% more inductive flux;
- An Improved Divertor featuring improved centre-column armour; smaller,
shaped P2 plates; and shingled main divertor plates. This is designed
to handle the high power loading expected during high performance operation.
Together with the re-positioning of the P2 coils, these modifications
will provide increased plasma performance and higher plasma elongation.
In addition, the NBI systems will be increased in power and pulse length;
and the Poloidal Field coil power supplies will be upgraded.
These changes will enable MAST to perform up to its design specification
of 2MA plasma current
EBW (Electron Bernstein Wave) antenna (using the Culham 60GHz
ECRH facility)
The new antenna, installed Sept 2002. There are 7 sets of mirrors
to give full control over direction, polarisation and focussing.
Up to 200kW per line (7 lines) is available.
This is being used in ECRH pre-ionisation experiments and tests
of EBW heating.
|
 |
 |
Replacement centre stack
To be installed in the major engineering break scheduled for
June 2003 - March 2004
The present central solenoid was repaired and re-wound in 1999
after an early insulation failure. For this reason, it has been
operated at reduced performance. A complete new centre column (central
TF winding, plus solenoid winding) has been manufactured. It features:
- Improved design
- Longer solenoid
- TF: operation at up to 92kA x 24 turns, giving 0.52T at R=0.85m
- Solenoid: swing from ± 55kA (cf. ± 40kA), giving
~ 1V-s
|
MAST Improved Divertor (MID)
|
Present divertor
(simple P2 plate, ribs on tank ends)
|
MID (to be installed in 2003)
shaped P2 plates; shingled tile divertor plates; improved c/col
armour
|
Mast layout for 2004
- Longer solenoid
- upper P2 coil raised by 10cm,
- lower P2 coil lowered by 10cm
- shaped P2 armour
- larger footprint for inner exhaust strike points
- controllable inner gas puff (arrowed)
- a top launch Pellet Injector will be incorporated
|
 |
February 2003 |
