Results from a 750 kJ Computer Controlled Sequentially-Fired Pulse Forming Network

The design of a 750 kJ sequentially-fired pulse forming network (SFPFN) is described and recent experimental results in the case of a linear load are presented and compared with simulations. The principal advantages of the sequentially fired network over its passive analogue are its utility in both linear and non-linear load applications. Operation of the SFPFN consists of charging multiple capacitor banks to various levels and sequentially firing these banks into the load at appropriate times. The load characteristics and desired pulse attributes determine the module charge voltage and sequential firing schedule. The SFPFN uses a computer controlled field programmable gate array (FPGA) to trigger the individual module firing intervals. The use of a computer controlled firing circuit provides an opportunity to incorporate realtime load monitoring and feedback to select optimal firing times and durations based on dynamic load conditions. Real-time monitoring also allows for firing sequence abortion in the event of a fault or other potentially harmful event. The charging controller features a computer monitoring and control system to allow a single power supply to charge multiple capacitor modules by an array of switching relays, even though each module may be charged to a different voltage. In linear load testing, the SFPFN provided a relatively constant current pulse to a resistive load