Investigation on high inductive helical supported magnetically insulated transmission line on a 10-stage linear transformer driver system

Abstract

Magnetically insulated transmission lines (MITLs), which could transfer power density up to $\mathrm{TW}/{\mathrm{cm}}^{2}$, are one of the most important technologies in pulsed power. In pulsed power systems for the $Z$-pinch fusion or radiography, a long MITL acts as a transmission line as well as a spatial isolation between load and driver. The length of MITLs in such systems will be up to a few, even tens of meters. However, the anode and cathode (A-K) gap is only a few centimeters to make the centering of the MITL's electrodes be one of the most challenging issues. Cathodes of long coaxial MITLs, such as that of Hermes-III and RITS, are fixed at the low voltage end while keeping the other end free of support. However, such a method will be very difficult for longer MITLs due to gravity and engineering reasons. An interesting question for such MITL design is to find a way to position the electrodes to the ideal position while hardly damaging the power flow. It is also a very practical concern in the construction of large pulsed-power facilities. In this paper, a high inductive helical supported MITL in a 10-stage linear transformer driver system is investigated. Both experiments and particle-in-cell simulations show that magnetic insulation is well established and power flow could be transmitted to load efficiently.