This proposal is for an innovative power system for small satellites that uses a closed-loop Brayton cycle heat engine to produce electric power.The system is shown in \figref{powersystem}. The miniature power plant drives a multi-phase permanent magnet generator with innovative power electronics to produce power from any fuel source. For spacecraft with mono-propellant thruster systems the same fuel would be used for the heat engine as is used for propulsion. The combustor is a modified thruster, such as an Aerojet-Rocketdyne hydrazine thruster hydrazine or green propellant thruster. The Brayton Cycle can be started or stopped quickly. The system is scalable from 100's of watts to 100's of kilowatts. The Brayton Cycle uses GE UPHEAT additive manufacturing technology for the recuperator and combustor heat exchanger. This technology results in very high efficiencies, low pressure drops and low masses. The power converters use Stony Brook University power electronics technology that can achieve power densities of greater than 34 kg/kW. The spacecraft power bus will use EnerSys industry leading batteries. EnerSys will also design the overall power system, Princeton Satellite Systems will integrate the entire system. A 1 kW system fits easily on an ESPA bus.
