Xenon ion-propulsion subsystem

Abstract

This paper describes an integrated xenon ion propulsion subsystem designed to perform 10 years of northsouth stationkeeping for 2500-kg-class geosynchronous communications satellites. The propulsion subsystem comprises a 25-cm-diam thruster, a power supply, and a propellant tankage and control unit. With a spacecraft bus power of 1400 W, the unit produces 63 mN of thrust at a specific impulse of 2900 s. A propulsion subsystem efficiency of 65% is obtained using a highly efficient ring-cusp discharge chamber equipped with a three-grid ion extraction assembly (thruster efficiency of 70%) and a simplified power supply that operates at 90% efficiency. Results show that the propulsion subsystems can be turned on with a single analog command, reaching its fullthrust level in less than 3 min.