Adiabatical Spherical Tokamak (TSP-AST) magnets

The TSP-AST tokamak is a new version of the TSP tokamak in which use is made of the adiabatic plasma compression over the major radius and formation of the spherical configuration in the final position. One of the requirements imposed on the TSP-AST tokamak is to make the most use of the main components of the existing TSP tokamak, to maintain the main mounting dimensions, weight-dimension characteristics and to keep the unique power supply system. The tokamak is designed to attain the limiting plasma parameters in the spherical configuration at powerful adiabatic compression; to define the plasma confinement scaling depending on A, k, and R at different positions of the plasma core along the vacuum vessel elongated over R, with the toroidal field, current and main plasma parameters remaining unchanged; to control the plasma core shape and to search for the equilibrium conditions, with the plasma detached considerably from the conducting wall elements. The total current in the magnets is 7.5 MA. The toroidal magnetic fields, B/sub T/ = 1.5 T and B/sub T/ = 3.5 T, are generated on the radius R/sub 0/ = 1 m and R/sub 0/ = 0.45 m, respectively. Despite relatively low magnetic field produced on the plasma core axis, the magnets of the TSP-AST tokamak operates under high electromagnetic loads. Therefore, development of an appropriate construction presents considerable engineering problems.