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Title: Upgrade for the NSTX Control Computer

The National Spherical Torus Experiment (NSTX) is a proof of scientific principle experiment as a magnetic fusion containment device. A primary goal of NSTX operations is control of the plasma current, position and shape in real time for a wide range of plasma pressure and current density profiles. In order to employ the best calculation of the plasma current, position and shape, it is planned to implement the equilibrium analysis code, EFIT, in real-time, RTEFIT. EFIT inverts the Grad-Shafranov equation and performs a least squares fit to the magnetics data. RTEFIT is also capable of providing the plasma current profile and the plasma pressure profile from analysis of diagnostic data. The calculation time for RTEFTI using the present NSTX control computer system is comparable to the expected energy confinement time on NSTX and is thus slower than desired. A computer upgrade based upon 604e processors will permit the RTEFIT calculation loop to complete in about 3 ms. The presence of the passive plates further complicates the control algorithm to be used in conjunction with RTEFIT. The planned approach is to measure the eddy currents in the passive plates and to use the transient response of the coils to minimize themore » total shell current effect.« less
Authors:
; ;
Publication Date:
OSTI Identifier:
7699
Report Number(s):
Cfpaper-4036
TRN: US0101815
DOE Contract Number:
AC02-76CH03073
Resource Type:
Conference
Resource Relation:
Conference: Institute of Electronical and Electronics Engineers, Sante Fe, NM (US), 06/14/1999--06/18/1999; Other Information: PBD: 1 Jun 1999
Research Org:
Princeton Plasma Physics Lab., NJ (US)
Sponsoring Org:
USDOE Office of Energy Research (ER) (US)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; NSTX DEVICE; COMPUTERIZED CONTROL SYSTEMS; MODIFICATIONS; E CODES; R CODES; CONFINEMENT TIME; CURRENT DENSITY; EDDY CURRENTS; GRAD-SHAFRANOV EQUATION; PLASMA PRESSURE