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T-15 is a mean-size tokamak which has been designed for experiments with circular plasma. Set of poloidal field coils includes ohmic heating coil and three pairs of ring equilibrium coils. These coils are situated outside the superconductor toroidal field coil. To increase volt-second capability, T-15 tokamak is equipped by iron core with twelve legs. As consequence self and mutual inductances and effectivenesses of plasma and poloidal field coils strongly depend on an iron core saturation. The presence of an iron core and legs results also in appearance of additional destabilizing forces. However stability analysis did not show instability of vertical or radial plasma motions. For plasma control purposes two additional coils have been mounted. "Saddle" coils produced vertical control field are located between toroidal field coils and vacuum vessel. Two pairs of ring coils produced horizontal control field are located outside toroidal field coil. These coil features weakly depend on an iron core saturation. The power supply of the poloidal coils consists of several separate thyristor converters.The plasma control system includes plasma current and plasma position programme and feedback controlled circuits. In feedback control PD-controllers are used. The investigation of control system using dynamic model has shown strong influence of poloidal coils stabilizing effect on plasma dynamics ("shell" effect) and weak dependence of PD-controllers gains on an iron core saturation. Preprogramming of equilibrium coils (current distribution) is based on adaption procedure which is realized during the dwell time.Magnetic measurements have shown that poloidal coils effectiveness were calculated with sufficient accuracy and coincided with measured ones within ten per cent. The magnet system assembly accuracy is well too and the stray field generated by toroidal field coils is small. That results in low voltage needed for plasma initiation (E = 0.8-1.2 V/m). In the first plasma experiments plasma current 500 ÷ 700 kA was reached at plasma density (0.6-1). 1019 m-3, toroidal field magnitude 1.5-2.7 T (safety factor qa = 3-4) and discharge time length 0.8-1.2 s. The volt-second consumption was about 4 V.s.

The basic problems of Tokamak-15 electromagnetic system (EMS) elaboration are discussed. The EMS design is described, its main component parameters and features are presented. The R and D program for the EMS design including its most complicated component, the superconducting toroidal field system (TF system), is considered. Post-assembly EMS tests comprising the achievement of a toroidal field nominal value and plasma discharges are described.