Vertical Position Control in TCV: Comparison of Model Predictions with Experimental Results
Growth rates of the axisymmetric instability of elongated plasmas in TCV are measured, in open loop configuration, for a wide variety of plasma shapes with elongation's and triangularities in the ranges, 1.3<k<2.2 and -0.3<g<0.6, respectively, and for stability margins covering the range 1.03<f<1.60. In addition, the stability of the vertical position control system is investigated experimentally, under closed loop conditions, by varying the feedback gains and by measuring the oscillation frequencies close to the stability limit. The results of these measurements are compared with theoretical calculations based on rigid and deformable plasma models. While the RPM model underestimates the open loop growth rate for large values of g and overestimates the size of the stable domain in gain space, the DPM model gives a very good agreement with the experimental results.
Bibliographic Reference: Paper presented: IAEA Technical Committee meeting on ECRH Physics and Technology for Fusion devices and EC-11, Oh-ari (JP), 4-8th October (1999)
Availability: Available from Librarian, Centre de Recherches en Physique des Plasmas, EPF, Lausanne (CH)
ISBN: ISSN 0458-5895
Record Number: 199911520 / Last updated on: 1999-10-29
Original language: en
Available languages: en