Power Source Options for an Aircraft Based Intermittent High Power Weapon Platform Application

Abstract

Pulsed power systems for directed energy weapon platforms are becoming increasingly important in modern combat situations. A general thermodynamic analytical investigation was developed to assess the impact of technological improvements on mission effectiveness and weapon power generation in an aircraft (a/c) based pulsed power system. The power system, for which the analysis is being conducted, essentially consists of six major components, a prime power source, electrical power generator, power conditioner, pulsed power source and pulsed power processor and the thermal management system (TMS) with a total estimated payload restriction of 4600 kgs., based on a USAF cargo aircraft. The a/c based power systems analysis corresponds to a notional aircraft mission, with the turbo- shaft engine operating at a fixed altitude. It has been assumed that heat from various system components is collected by the same coolant loop, and then rejected to ambient air in a ram air heat exchanger (RAHX). The analysis was based on a Multi-MW class pulsed power source output and a notional mission profile with an engagement period of 60 minutes during which several duty cycle scenarios were considered. The power system components were sized to accommodate the power requirement represented by the respective duty cycle of operation. Several power system architectures were evaluated with a baseline power system model that incorporated current off-the-shelf (OTS) technologies for each component. The baseline power systems analysis was conducted to size a power system for steady state operation at peak load during an individual engagement. A stand-alone turbo shaft engine was used as the primary power source because of its high power density but the engine performance is very sensitive to increasing altitude where the output power diminishes rapidly. As a result of this and the necessity to accommodate load sharing or load following during engagement, the investigations were extended to the hybrid power system architecture with turbo alternator-battery and turbo alternator-flywheel combinations.