1 / 6

Merging-Compression Start-up

XP511. Merging-Compression Start-up. Y. Takase, Y. Ono, O. Mitarai, D. Gates, J. Menard, R. Raman, J.R. Wilson, M. Yamada, S. Zweben, et al. New scenario of solenoidless start-up by merging of two STs formed by external PF coils Advantages: 1) high-power heating 2) electrode-free

carver
Download Presentation

Merging-Compression Start-up

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. XP511 Merging-Compression Start-up Y. Takase, Y. Ono, O. Mitarai, D. Gates, J. Menard, R. Raman, J.R. Wilson, M. Yamada, S. Zweben, et al. New scenario of solenoidless start-up by merging of two STs formed by external PF coils Advantages: 1) high-power heating 2) electrode-free 3) high efficiency hmerging (>> hRF) startup of ST plasmas. Flux for separation (field index control) EC ionization Flux for formation/ merging

  2. ST Merging (TS-3): High power heating of merging enables quick formation of a high-b ST plasma

  3. Coils ST ST ECH ST ST ST TS-3/4 Coils 1) Two merging STs were produced by internal PF coils (TS-3/4)2) One ST/tokamak was produced by external PF coils with ECH (TST-2, JT-60). Merging start-up of high-b ST without X-points

  4. Smal l ST Coils ST ECH ST ST Coils Smal l ST New Merging ST Experiment (@ Univ. Tokyo) Merging of two STs produced by external PF coil induction at X-points  high-b ST startup We can expect • MW-GW class heating power 2) Efficient formation of ST without CS coil 3) Injection of toroidal flux (helicity) 4) Profile control effect Can also explore current-drive by intermittent merging

  5. Example of LRDIAG Simulation Bt = 4.5 kG Optimization with updated PF1A will be completed prior to execution of XP

  6. Planned sequence 1) Start with merging scenario with X-point • Two field nulls are created inside the vacuum vessel (top/bottom) by PF1A and PF5 coils • PF2, PF3 and PF5 are used to drive current and compress the plasma • About 100 kA of plasma current is expected to be driven, if successful 2) Optimize current rise • Vary initial field null configuration • Vary subsequent poloidal field evolution for merging and compression 3) If successful, try merging scenario without X-point • Available EC power may be insufficient for this scenario This experiment requires diagnosis of start-up plasma at low current and low density.

More Related