Modification and Testing of a Battery-Inductor Repetitive Pulsed Power Supply for a Small Railgun

Abstract

Pulsed power supplies for electromagnetic launch have unique requirements, including very low impedance, relatively long pulse discharge times, and high stored energy. The three primary types of pulsed power systems for electromagnetic launch have been capacitive, inductive, and rotating machine. This paper describes recent results in the design, construction, and testing of a pulsed power system based on an inductor that is charged by batteries. A battery-inductor-based pulsed power supply has several advantages over pulsed alternators and capacitor-based pulse-forming networks. Because an inductor system stores its energy in a magnetic field, it eliminates the moving parts found in rotating machines, while having significantly higher energy density than capacitor-based systems. These features offer tremendous benefits in the design and operation of a fieldable pulsed power supply. Advances in high-power lithium-ion batteries (which allow for a smaller battery pack) and the inherent high energy density of inductors imply that the overall energy density of a battery-inductor based power supply can be smaller then a capacitor-based system and potentially comparable to a rotating-machine pulsed power system. Work on battery-inductor based pulsed power has continued at the Institute for Advanced Technology (IAT). This paper describes the modification of an inductive pulsed power supply discussed in previous work. The modifications included the addition of batteries for the prime power, using a smaller turn-off switch and a capacitor bank that had a higher capacitance.