Abstract: During the launching of electromagnetic rail-gun, the distributed power supply system would suffer more than 30 kA pulse current and more than 5 kV pulse voltage within 2 ms, which has great effect on the critical components of power supply system. Research on the impinging characteristic of distributed power supply system during the launching of electromagnetic rail-gun is very important. A distributed pulse power supply system model with dynamic load variation is established. The impinging characteristics of the distributed pulse power supply system and its working characteristics after the failure of critical components are simulated using Pspice software, and the analysis results are compared with the experimental results. The results show that, during the launching of electromagnetic rail-gun, the capacitor bank of distributed power supply system would suffer large reverse current and reverse voltage after thyristor breakdown, which causes serious damage to the capacitor bank. After the wave modulated inductance is breakdown, the output waveform pulse width of fault module is similar to the output waveform of capacitor bank, and it causes the pulse width of output waveform decrease peak value increase（di/dt of current that though the thyristor increase）, it may cause the high voltage silicon rectifier stack of thyristor positive flow burned. The simulated results are in good agreement with the experimental results, which proves that the power model of electromagnetic rail gun is very close to the practical model, and the result is more accurate and credible. Key

Key words: ordnancescienceandtechnology, electromagneticrail-gun, distributedpowersupplysystem, dynamicload, impingementcharacteristic