Analysis of Projectile Motion in Bore and Transfer Efficiency for Electromagnetic Railgun

Electromagnetic railgun (EMG) use a high-current, high-energy electrical pulse to accelerate projectiles to hypersonic velocities. A pulsed power supply (PPS) that employ capacitors as the energy store are typically used to shape the required electrical pulse. In this paper, the differential equations of projectile moving in the bore has been given and solved. The general pattern of projectile moving in the bore has been studied. Considering the influence of current fluctuation on velocity, the stability of armature has been discussed. In order to improving system performance, the efficiency of main energy transfer process has been calculated. The influence of current shape consists of several electrical pulse on muzzle velocity and efficiency has been studied. And some important conclusions have been reached, which provide theoretical references for guiding railgun design and choosing waveform of discharging current.