Passive Feedback Control of Plasma Position in a Tokamak

抄録

The effect of many passive coils on the positional instabilities in tokamaks is numerically investigated in the case of t<<τ_e (effective skin time of the coils), assuming the rigid shift of the plasma column. In order to make the positional stability region of the decay index broader, the passive coils must be located as close as to the plasma surface with the optimum position. The skin time of the coils is determined mainly by the number, cross section area and the conductivity of the coils. Application of the analysis to two small tokamaks shows the fairly good agreements with the experimental results.