Circuit simulation of Saturn with a reflex triode load

Abstract

A new circuit model for the Sandia Saturn generator [1] was constructed to aid analysis of measurements from recent experiments with reflex triode loads [2]. This configuration is easier to model than others because there are no convolutes in the vacuum region. Also, the low impedance of the reflex triode makes the amount of vacuum flow current insignificant, which also simplifies analysis. Saturn has 36 identical pulse generator modules that each drive a water transmission line output. These transmission line outputs are bussed together in water before driving the vacuum insulator stack. Measured voltage waveforms from all 36 of the water transmission lines (TL) are used to drive the simulation. The 94-ns two-way electrical length between the location of the TL voltage probe and the end of the TL makes the measured TL voltages a high fidelity input for the simulation. The load currents from the circuit model are compared to measured currents for short circuit and real load shots. A physics-based circuit model for the reflex triode was used to aid in analysis of the reflex triode behavior.