| Presentation: | submitted: | by: |
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| wrobel_icc__3_.pdf | 2007-04-02 11:09:27 | Jonathan Wrobel |
HIT-SI Machine Upgrades
Author: Jonathan S Wrobel
Requested Type: Poster Only
Submitted: 2006-12-15 15:20:42
Co-authors: T.R.Jarboe, R.Z.Aboul Hosn, C.Akcay, W.T.Hamp, R.G.O’Neill, B.A.Nelson, A.J.Redd, R.J.Smith, B.T.Stewart
Contact Info:
University of Washington
AERB Rm 120, Box 352250
Seattle, WA 98115-2
USA
Abstract Text:
HIT-SI has successfully established spheromaks of 28kA using only 6MW of helicity injection power. Further advancements have been hampered by the capability of the insulating wall in the injectors. Machine upgrades are underway on the insulating wall and other areas to further increase spheromak performance. Testing has been done on new plasma facing insulating coatings for the HIT-SI vessel, to identify a stronger insulating coating that may withstand higher injector voltages. The diagnostic gap that separates the close fitting conducting wall in HIT-SI will be fitted with an enhanced copper bridge to reduce flux leakage. Improved performance has been observed in operations with a copper strap bridging the diagnostic gap, motivating the upgrade to a more effective conductive bridge with longer L/R time. Feedback is also being developed to counter resistive wall modes and help correct for long term soak through of fields into the flux conserver. Modification of the injector flux coil winding configuration will increase efficiency and minimize field errors that lead to plasma-wall interactions. In conjunction the power supply available to the injector flux coils will be doubled through the addition of 8 more Switching Power Amplifiers. Installation of a new turbo pump will increase pumping speeds from 450 to 1100 L/s, in efforts to further reduce base pressure and allow greater gas loads during a shot, increasing the available operation space.
Characterization: A3
Comments:
Please place with other HIT-SI posters.
