An Alternating Current Tokamak Reactor with Ohmic Ignition and Bootstrap Current

Publisher Website
Google Scholar
Abstract
An alternating current (ac) tokamak reactor with ohmic ignition and long pulses due to bootstrap current is proposed as a simple and quasi-continuous fusion power plant. An ohmic plasma current of 23 MA with a high toroidal field of ∼10 T in the Alternating Current Tokamak Reactor-Upgrade (ACTR-U) (10-m major radius and 2-m minor radius) provides the ohmic ignition. After entering the ignition regime, the plasma current is reduced by one-half to enhance the bootstrap current with a high-beta poloidal field (βp ∼ 2) to prolong the pulse length. When the ohmic transformer reaches the maximum flux, the plasma current is ramped down and reversed; ac operation follows. We thus demonstrate that an ohmic transformer alone is in principle sufficient for a quasi-continuous deuterium-tritium fusion reactor.