PARAMETRIC SCALING STUDY OF A MAGNETICALLY INSULATED THERMIONIC VACUUM SWITCH

A parametric scaling study is performed on MINOS (Magnetically INsulat ed Opening Switch), a novel fast (similar to 100 ns) high-power openin g switch concept based on a magnetically insulated thermionic vacuum d iode. Principal scaling parameters are the switch dimensions, voltage, current, applied magnetic field, and switching time, The scaling rang e of interest covers voltages up to 100 kV and currents of several kA. Fundamental scaling properties are derived from models of space-charg e flow and magnetic cutoff, The scaling is completed with empirical re sults from the experimental MX-1 switch operated in an inductive stora ge pulsed power generator. Results are presented in diagrams showing v oltage, current, power, and efficiency relationships and their limitat ions, The scaling is illustrated by the design of a megawatt average p ower opening switch for pulsed power applications. Trade-offs in the e ngineering of this type of switch are discussed.