Investigation of an alternator charged pulse forming network with flywheel energy storage

The authors present the conceptual design of a system to power an 18-shot, salvo fire 30 mm railgun. The performance of components was selected to be slightly beyond the state of the art but achievable in the near term. For instance, the baseline PFN utilizes a 935 kJ capacitor bank made up of Aerovox 1.3 J/g, 2.5 A/J, 80% efficient capacitor technology. It was sized assuming a 33% efficiency from capacitor to launch package. These capacitors would require some development and are based on the 1.5 J/g technology developed under the BTI/Army Pulse Power Module Program. The 1.5 J/g technology is based on high-voltage (24 kV), low-current capacitors. 1.3 J/g is estimated for lower-voltage (8 kV), higher-current devices. The alternator has power density of about 12 kW/kg. Compulsators have demonstrated peak powers of 100 kW/kg and are being designed to produce 500 kW/kg. The energy storage flywheel design is based on the minimization of overall system mass