Pulsed Operation of a Combustion MHD Generator

A combustion-driven MHD power generator has been operated in a repetitively pulsed mode for the first time. It is shown that rapid modulation of plasma conditions causes the MHD generator to act as a high-power switch. This technique was demonstrated in a self-excited circuit to produce a regular train of sharp megawatt power pulses. The rise and fall times achieved in these experiments can be reduced by at least an order of magnitude by a simple rearrangement of the control on the plasma conditions. A second useful characteristic of the MHD generator is the capability of the self-excited MHD magnet to serve as a combined inductive store and pulsed transformer to produce very-high-power pulses. Individual turns of the MHD magnet can serve as the secondary winding of a pulsed transformer with very efficient coupling, as has been confirmed by recent measurements. Analysis of a 5MA repetitive pulsing circuit using a self-excited MHD generator is presented. These results show the unique flexibility of the MHD generator for pulsed power applications.