Study on the poloidal magnetic fields in the ''Tuman-3'' device

Results of the study on the poloidal magnetic fields using the ''Tuman-3'' device are presented. The magnetic circuit core located near plasma area (the aspect relation of the device R/a is 2.3) considerably affects the conditions maintaining plasma filament equilibrium. The data experimental study are compared to the calculated data obtained when solving the magnetostatic problem in axial symmetry approximation. The calculated data are in agreement with the experimental ones to an accuracy of approximately 5% for the given model of the magnetic circuit. With the coil configuration of the poloidal field chosen the stability of plasma filament equilibrium on a large raduis is maintained, the instability along the vertical being weak. The shape of plasma filament section is close to circular. The poloidal magnetic field characteristics in the chosen mode of operation of the device weakly depend on the magnet core saturation coefficient. In developing the control system of plasma filament position the results of measurements have been used