Current and beta limitations for the TCV tokamak
Initial ideal MHD stability results for the Tokamak Configuration Variable (TCV) tokamak with variable elongation are presented. Two configurations have been studied: a racetrack shape and a D-shape at a fixed elongation of 2.5. Low beta studies indicate the existence of stable racetrack equilibria at currents up to an edge safety factor value of q(s) = 2, but the window of operation is limited in q(o) to narrow bands above each integer value. For the D-shape, q(s) = 3 gives the current limit at low beta, but the operating range in q(o) is much wider than that for the racetrack. Beta optimization studies show that the maximum beta set by the n = 1 free-boundary stability limit decreases as the current increases, except for the lowest currents in the range studied. Although further optimization cannot be ruled out, considerable enhancement of the beta over that for an equivalent circular cross-section of the same major radius and aspect ratio can be obtained by elongation of the plasma cross-section.
Bibliographic Reference: Article: Nuclear Fusion, Vol. 28 (1988) No. 8, pp. 1379-1383
Record Number: 198910183 / Last updated on: 1994-12-01
Original language: en
Available languages: en