Comparison of Two Railgun Power Supply Architectures to Quantify the Energy Dissipated After the Projectile Leaves the Railgun

Railgun muzzle flash, or post-fire arcing, is a major concern to the Navy because of the potential associated thermal stresses. In this thesis, we compared two railgun power supplies in Matlab Simulink to quantify their associated post-fire energy. When the armature exits the rails, a finite energy from the railgun pulsed-power supply is inductively stored in the rails and discharges at the muzzle. This energy, which is due to the loss of the low-voltage electrical contact that is ordinarily between the armature and the rail, is forced by the system inductance to flow as an electrical discharge, creating a muzzle flash. Quantification of this post-fire rail energy in our simulation from both the existing railgun power supply and the proposed power supply--a thyristor-based power supply versus a buck-boost converter, respectively--reveals that the buck-boost converter topology is better suited for the railgun, particularly at minimizing the post-fire muzzle energy. The minimization of the post-fire energy allows for an extended rail life and potentially longer usage.