Superconducting toroidal

G. Krafft, Cooling Methods for Superconducting Toroidal Field Coils, Internal Report of the Kernforschungszentrum, Karlsruhe, West Germany (1976). 

Table II. Superconducting Tokamaks and Toroidal Test Coils (Proposed or under...

The measurement transformer is shown in Fig. 3 both in the assembled form and in an open schematic layout. The magnetic core of the transformer is of solid ingot iron and is toroidal in shape. Although unnecessary to dc operation, a superconducting wire is used for the primary winding. Copper wire would... 

The superconducting magnet system would probably be the most expensive part of a tokamak reactor. The typical target data for developing the toroidal magnet are shown in Fig. 3. 

The on-site fabrication of such huge superconducting coils involves large technical problems, particulary as regards quality assurance. As already mentioned, it is assumed that the toroidal field coils in tokamaks cannot be replaced, and it is an open question, if the extremely high reliability therefore required can ever be achieved. 

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