| Popis: |
Analytic formulas for the computation of the toroidal field ripple in a tokamak with saddle coils and/or magnetic inserts for the reduction of the ripple are derived. The results of these analytic formulas compare well with the results of a 3D magneto static code for the geometry of Tore Supra and ITER. In Tore Supra 72 saddle coils with 5% of the toroidal field coils current or 36 magnetic inserts 12 cm thick are needed to reduce by a factor of four the ripple in the outboard region of the plasma. In ITER, using ferromagnetic rather than austenitic balls in the space between the vacuum vessel skins, would partially offset the ripple-increasing effect due to the reduction of the number of TF coils from 24 to 20. |
