125kV, 100kA, 150ns, 5pps test facility with solid state switched distributed pulse compression?

Electra is a repetitively pulsed, electron beam pumped Krypton Fluoride (KrF) laser at the Naval Research Laboratory. [1] This program is developing technologies to meet the Inertial Fusion Energy (IFE) requirements for durability, efficiency, and cost. The Electra laser main amplifier requires a 500kV, 100kA, 150ns, 5Hz pulsed power source. At present, the main amplifier uses gas insulated spark gap switches with lifetimes of 10
⁵
pulses. Solid state switched pulsed power sources are being developed to achieve lifetimes of 10
⁸
pulses. Applied Pulsed Power has developed a 48kV compact solid state switch for this application that operates at 8kA and can withstand fault currents of 14kA and 80% current reversal. Individual modules used in the switch have been tested for ¿200 million pulses without failure, and lifetime testing of the complete switch is in progress. Using these switches, we are manufacturing and testing a quarter scale version of the Electra pulsed power source. Scaling was done by reducing the number of Marx stages and the impedance of the downstream pulse forming components and load by a factor of four, resulting in a 125kV, 100kA, 150ns, 5pps test facility. This approach ensures that each Marx stage operates at the design voltage and current, and the pulse forming components and magnetic switches operate at the same design current and timing as for the full scale system. The electric fields in the pulse forming components for the quarter scale version exceed the design values for the full scale system.