Stabilization of the 'resistive sheel mode' is vital to the success of the 'advanced tokamak' concept. The most promising reactor relevant approach is to apply external feedback using, for example, the previously proposed 'fake rotating shell' scheme. This scheme, like other simple feedback schemes, only works if the feedback controlled conductors are located inside the 'critical radius' at which a perfectly coducting shell is just able to stabilize the ideal external kink mode. In general, this is not possible in a reactor since engineering ocnstraints demand that any feedback controlled conductors be the fake rotating sheel feedback scheme can be modified so that it works even when the feedback controlled conductors are located well beyond the criticla radius. The gain, bandwidth, current and total power requirements of such a feedback system for a reactor sized plasma are estimated to be less than 100, a few Hz, a few tens of kA and a few MW, respectively. These requirements could easily be met by using existing technology. It is concluded that feedback stabilization of the resistive shell mode is feasible in a tokamak fusion reactor.
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