Skip to main content
Log in

Initial Experiments at High Normalized Current in the Pegasus Toroidal Experiment

  • Published:
Journal of Fusion Energy Aims and scope Submit manuscript

 

Initial experiments in the Pegasus ST exhibited an operational limit of I pI tf at A ∼ 1.15. With new power supplies, discharge control has greatly increased. Equilibria and stability modeling of the high I p/I tf regime has produced stable equilibria with I p/I tf up to 2 while values of I p/I tf approaching 3 show a potential upper bound on stability. A new operating regime has been accessed in recent experiments with the addition of electrostatic plasma sources. Using the sources as a pre-ionization technique, I p/I tf values of 1.5 have been accessed at very low toroidal fields. Using the sources as a means for non-inductive startup, values of I p/I tf up to 2.3 are attained. The MHD activity in these discharges is characteristically different than ohmic discharges, suggesting the new current sources are modifying the current profile to allow stable discharge evolution at minimal toroidal field.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.

Similar content being viewed by others

References

  1. Peng Y.-K. M., Strickler D. J. (1986) Nucl. Fusion 26:769

    Google Scholar 

  2. Troyon F. (1984) Plasma Phys. Control. Fusion 26:209

    Article  Google Scholar 

  3. Hender T. C., Allfrey S. J. et al., (1999) Phys. Plasmas 6:1958

    Article  Google Scholar 

  4. Garstka G. D. et al., (2003) Phys. Plas. 10:1705

    Article  Google Scholar 

  5. G. D. Garstka et al., (2006) Nucl. Fusion 46:S603

    Article  Google Scholar 

  6. K. Tritz, Ph.D. thesis, University of Wisconsin—Madison (2002)

  7. Glasser A. H. (1997) Bull. Am. Phys. Soc. 42:1848

    Google Scholar 

  8. N. W. Eidietis et al., (2003) Bull. Am. Phys. Soc. 48:270

    Google Scholar 

  9. N. W. Eidietis et al., These proceedings

Download references

Acknowledgments

This work is funded by U.S. Department of Energy Grant DE-FG02-96ER54375.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to E. A. Unterberg.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Unterberg, E.A., Battaglia, D.J., Bongard, M.W. et al. Initial Experiments at High Normalized Current in the Pegasus Toroidal Experiment. J Fusion Energ 26, 221–225 (2007). https://doi.org/10.1007/s10894-006-9056-z

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10894-006-9056-z

Keywords

Navigation