The Development of a 1 MV 40 kJ Marx Generator and Pulse Forming Line System

This text describes the design and testing of a 1 MV output Marx generator test bed to be used for large scale laser triggered gas switches. The 9-stage bipolar Marx generator is derived from a Marx generator module originating from the decommissioned RITS Accelerator. The Marx generator is housed in an existing oil tank and feeds into a 10 Ω pulse forming line. This oil filled coaxial PFL has a one-way transit time of 30 ns. Connected to the end of the line is a self-breaking peaking gap and load section. The load section is oil-filled and includes a matched impedance aqueous resistor load. The megavolt Marx generator is triggered by a mini-Marx generator. The mini-Marx is an 8-stage unipolar line-of-sight Marx generator with an output of up to 400 kV. This Marx is triggered by a solid state pulser. All diagnostic and control signals feed into and out of a screen room at a safe location for the operator. Diagnostics include a Rogowski coil to measure the Marx generator current, a quarter-turn Rogowski coil to measure load current, and capacitive voltage dividers on either side of the peaking gap to measure line and load voltages. High voltage charging of the Marx generators and triggering of the solid state pulser is done through fiber optic control. Various relays used to dump charge on the Marx generators and disconnect high voltage power supplies are controlled through a DIN rail control panel with user inputs located in the screen room.