Design and construction of a 250 kV, 100 Hz repetitive Vircator test stand

The Center for Physical and Power Electronics (CPPE) at the University of Missouri-Columbia is investigating the applicability of utilizing two separate Vircators simultaneously for multipulse testing. To facilitate this research, we have designed and constructed a versatile modulator to drive the HPM sources that allow us to drive two Vircators in parallel. The modulator consists of a thyratron-switched capacitor bank that pulse charges a water transmission line through a pulse transformer. The water transmission line is then switched into a voltage adder by a pressurized oil switch with an output risetime of 20 ns. The capacitor bank is charged to 30 kV by a bank of power supplies delivering up to 40 kJ/s and switched by a thyratron into the pulse transformer. The 1:10 pulse transformer charges the water line to 300 kV in approximately 2.5 μs. When driven by the pulse line, the 250 kV output voltage is utilized to simultaneously drive the two, 32 Ω Vircators in parallel or a 16 Ω load with a 70 ns long pulse. We will present details of the design, including particle-in-cell simulations using CST Particle Studio and SPICE circuit simulations of the Vircator design and modulator design, as well as construction details. The test results will also be presented.