Application of superfluid helium cooling techniques to the toroidal field systems of tokamaks

Practical considerations on conductor design criteria in superfluid helium are presented, discussed and compared to design criteria in supercritical helium. Results show that the operating temperature has a critical influence on the cost of the system and can be determinant in the choice of the superconducting material. Some economical analysis are given based on a reference toroidal field magnet concept.