In the paper the problem of plasma control in the toroidal magnetic chamber of ITER tokamak is investigated. Extreme physical conditions in tokamaks lead to very high requirement to control accuracy for electromagnetic capture system while positioning plasma within given gaps from the walls of chamber. On the other hand, real conditions restrict some characteristics, such as control power. Mathematical methods of stabilizing control design based on modern optimization theory are proposed. These methods were designed to increase control efficiency by redistributing its power between tasks.