Effect of Sequence Discharge on Components in a 600-kJ PPS Used for Electromagnetic Launch System

Pulsed power supply (PPS) applied in the electromagnetic launch system must have a compact design and high reliability. In this paper, a PPS for electromagnetic launch system is built up. The main parts in a pulse forming unit (PFU) of a PPS are energy storage capacitors (8 kV/75 kJ), pulse-shaping inductor (10 mu H), pulse thyristor, crowbar diode, and a Rogowski coil for current measuring. The energy storage density of the PFU is 0.74 MJ/m(3). Eight PFUs form a pulse forming network (PFN) of 600 kJ. In many cases, the discharge current waveform of the PFN must be adjusted for lower peak value and lower electromagnetic force. On the basis of this PFN, in this paper, we analyze the effect of sequence discharge on the semiconductors. To prevent diode from overvoltage during the recovery process, different parameters of snubber circuit have been researched in the experiments. Finally, we set up a model of the serial augment rail gun in a personal simulation program with integrated circuit emphasis, and the safety of PFU can be affirmed by simulation if the voltage of the rail gun keeps positive during the course of the discharge.