URAGAN-2M - A TORSATRON WITH AN ADDITIONAL TOROIDAL FIELD

The analysis of an l = 2 torsatron with a relatively small pitch angle of the helical winding, which requires an additional toroidal field (TF), is presented. The main advantage of this torsatron design, as compared with a conventional torsatron having a large helical winding pitch angle and no TF coils, is the reduction of the helical winding current and the helical ripple of the magnetic field. This facilitates construction and operation of the most complicated component of the magnetic system, the helical winding, and also reduces the plasma losses due to magnetic field ripple. An experimental device of this type, URAGAN-2M, now under construction at the Kharkov Institute of Physics and Technology, is described. The reactor prospects of this concept are also discussed.