4 MW upgrade to DIII-D FWCD system: system commissioning and initial operation
W.P. Cary, F.W. Baity, G.C. Barber, R.W. Callis, J.S. deGrassie, S.W. Ferguson, T.E. Harris, R.C. O'Neill, R.I. Pinsker · 2002
The initial installation of the 4 MW fast wave current drive (FWCD) upgrade started in 1992 with the purchase of two ABB/Thomcast AG RF power amplifiers. These amplifiers cover the frequency range 30 MHz to 120 MHz. A maximum output power of over 2 MW between 30 MHz and 80 MHz and 1 MW at 120 MHz were the specification requirements. The system as installed is comprised of the two mentioned RF amplifiers, coaxial transmission and matching components, RF phase and amplitude monitoring, and a SUN SparcStation 10 control system. Due to various reasons almost every major component in the system required redesign and engineering in order to meet the system requirements. The failures, probable cause and the final redesigns will be discussed as well as some thoughts on how better to specify system requirements for future systems.