Upgrades to the 4-strap ICRF Antenna in Alcator C-Mod
A 4-strap ICRF antenna suitable for plasma heating and current drive has been designed and fabricated for the Alcator C-Mod tokamak. Initial operation in plasma was limited by high metallic impurity injection resulting from front surface arcing between protection tiles and from current straps to Faraday shields. Antenna modifications were made in February 2000, resulting in impurity reduction, but low-heating efficiency was observed when the antenna was operated in its 4-strap rather than a 2-strap configuration. Further modifications were made in July 2000, with the installation of BN plasma-facing tiles and radio- frequency bypassing of the antenna backplane edges and ends to reduce potential leakage coupling to plasma surface modes. Good heating efficiency was now observed in both heating configurations, but coupled power was limited to 2.5 MW in H-mode, 3 MW in L-mode, by plasma-wall interactions. Additional modifications were started in February 2001 and will be completed by this meeting. All the above upgrades and their effect on antenna performance will be presented.
- Research Organization:
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC02-76CH03073
- OSTI ID:
- 786538
- Report Number(s):
- PPPL-3575; TRN: US0108930
- Resource Relation:
- Other Information: PBD: 12 Jun 2001
- Country of Publication:
- United States
- Language:
- English
Similar Records
Initial Operation of the Alcator C-Mod ICRF Antennas with High-Z Metal Antenna Guards
ICRF antenna designs for CIT and alcator C-Mod