Abstract. The NB H&CD system, providing 33 MW in deuterium beams at 1 MeV from two injectors, in addition to 40 MW RF power, contributes to heating a plasma to sub-ignition through the L-H mode transition followed by finite-Q driven-burn (Q 10), and achievement of a hybrid operation with an extended-duration ( 1000 s) or steady-state operation with Q 5. To achieve such operations, the NB provides non-inductive current drive by injecting the beams tangentially into the plasma with the capability of on- and off-axis current drive. The present engineering design is under the constraints of the beam envelope, vacuum confinement, neutron shielding, tolerances, and clearances required with the toroidal field coils. The on- and off-axis current drive is to be achieved by tilting the beam axis vertically. Each beam axis of the NB injectors can be tilted independently, providing flexibility in the control of heating and the driven current profile.
IAEA 2001