Electrical modeling of mercury for optimal machine design and performance estimation

Mercury is a new pulsed-power generator at NRL, having been transferred from FZK (Forschungszentrum Karlsruhe, Germany) where it was known as KALIFHELIA [R. J. Commisso et al., 2003; P. Hoppe et al., 2001]. Mercury is an MIVA (magnetically-insulated inductive voltage adder) designed to produce 50-ns pulses with load voltages up to 6 MV at a current of 360 kA and deliver 100-kJ of energy to the load [J. Fockler et al., 1993]. The inductive and resistive components connecting the Marx bank and the intermediate stores have been reconfigured to fit into one "machine tank" and to improve energy transfer, allowing for a reduced Marx charge voltage. A detailed circuit model was developed for Mercury based on an earlier model for KALIF-HELIA and updated to include new information and data from FZK. Circuit element values for the MIVA and the load were determined through PIC simulations. Good agreement between measured and calculated current and voltage peaks was found using the model fed by voltage signals measured upstream of the MIVA on KALIF-HELIA. Detailed modeling has shown that the original design parameters of the machine can be met at NRL.