A solid state switched power supply for simultaneous capacitor recharge and railgun operation

Abstract

A capacitive power supply for driving a railgun load has been developed using solid-state electronic switchgear and computer-grade electrolytic capacitors. These choices provide relative ease of component orientation and insensitivity to field conditions. The circuit is constructed so that half the bank capacitance is initially charged while the other half is uncharged. both halves are connected in series with the load, and diodes across each prevent voltage reversal. When the discharge is initiated, the current passing through a railgun simultaneously charges the uncharged section of the capacitor bank. Modeled and actual circuit performance results from a four-module supply, with 7500 J and 30 kA per module, are presented. It is concluded that this type of supply is ideal for use with augmented and multiturn railguns. In these configurations the pulse-shaping inductance becomes part of the railgun itself. A feature of this arrangement which may be exploited is zero current crossing with projectile exit; this is required for flashless firing and reducing tip-off of the projectile upon launch. >