Fusion reactor control

The International Thermonuclear Experimental Reactor has the need for feedback control of both the fusion output power and the driven plasma current while avoiding the possibility of damage to divertor plates. The response speeds are estimated for transfer functions that could be used in analyzing these two needs, expressed as ratios, kinetic temperature and plasma density increases, each per an injected fuel density rate increment. The ratio of increments, kinetic temperature to injected fuel density rate, is a nonminimum phase-shift transfer function for both DD and DT, with zeros in the right-hand s-plane. Speed of response for reactors using DD or DT is easily controllable, with the last break point occurring at about 0.8 Hz. The DD or DT reactor would self-protect against transients and be incapable of running away. The DD reactor would be unstable for temperatures up to 100 keV because of its positive temperature coefficient but stable at 700 keV