An university-scale pulsed-power system using a parallel plate capacitor bank

A parallel plate capacitor bank is being built for x-ray sources or laboratory astrophysics and space research for university-scale laboratory. The system consists of twenty 1 μF capacitors, two rail-gap switches, two parallel plate transmission lines, and a cylindrical vacuum chamber orientated vertically. Two capacitors are first connected in series forming a stage. Ten stages are connected in parallel as a capacitor bank and charged up to 80 kV. The capacitor bank is separated in two groups, i.e., five stages in each group, located on two opposite sides of the chamber. Parallel plate transmission lines are used to conduct current from each group of capacitor banks to the bottom of the cylindrical vacuum chamber where the high voltage feedthrough locates. The calculated system inductance is in the order of 50 nH. The total capacitance and the stored energy of the system are 5 μF and 16 kJ, respectively. The estimated rise time and the output current are ~800 ns and ~800 kA, respectively. However, the system will be charged to only ~20 kV for testing when it is first built. The experimental discharge characteristics will be given.