Implementation of βn control in the national spherical torus experiment

S. P. Gerhardt, D. Mastrovito, M. G. Bell, M. Cropper, D. A. Gates, E. Kolemen, J. Lawson, B. Marsala, J. E. Menard, D. Mueller, T. Stevenson

Research output: Contribution to journalArticlepeer-review

10 Scopus citations


We have designed and constructed a system for control of the normalized β (βN) in the National Spherical Torus Experiment [M. Ono et ah, Nucl. Fusion, Vol. 40, p. 557 (2000)]. A proportional-integral-derivative operator is applied to the difference between the present value of βN (from real-time equilibrium reconstruction) and a time-dependent request in order to calculate the required injected power. This injected power request is then turned into modulations of the neutral beams. The details of this algorithm are described, including the techniques used to develop the appropriate control gains. Example uses of the system are shown.

Original languageEnglish (US)
Pages (from-to)11-18
Number of pages8
JournalFusion Science and Technology
Issue number1
StatePublished - Jan 2012

All Science Journal Classification (ASJC) codes

  • Civil and Structural Engineering
  • Nuclear and High Energy Physics
  • Nuclear Energy and Engineering
  • General Materials Science
  • Mechanical Engineering


  • NSTX
  • Neutral beam injection
  • Spherical torus


Dive into the research topics of 'Implementation of βn control in the national spherical torus experiment'. Together they form a unique fingerprint.

Cite this