Ignition studies of D-3He spherical tokamak reactor

Abstract

Ignition access in a neutron lean D-3He fusion reactor is presented using a spherical tokamak (ST). The small central solenoid (CS) or the iron core transformer placed in the center provides the initial plasma current up to 1 ∼ 4 MA, and then the heating power and vertical field ramp up the plasma current up to 100 MA in this proposed D-3He ST reactor. This is operated in the thermally stable low density and high temperature regime. In this proposed machine, 14.7 MeV proton ripple loss has been calculated using the ORBIT code and it was found the low temperature and high density operation regime is favorable for reducing the ripple losses. For this purpose, the low-temperature and high density operation has been demonstrated in a D-3He fusion using the impurity injection method. Finally the D–D ignition access is demonstrated when 3He fuel is changed to D after reaching the D-3He ignition regime in this proposed ST reactor.