High-Efficiency Radiation-Hard Solar Array Interface to Spacecraft Power System

Electric orbit-raising offers significant advantages to GEO spacecraft users and operators by providing an order of magnitude improvement in the specific impulse of the propulsion subsystem, decreasing the required spacecraft fuel mass by as much as 90%. However electric thrusters also increase the time to station by months.Currently, the majority of GEO spacecraft do not utilize the maximum available solar array power at the beginning of mission life. If a spacecraft could utilize this additional solar array power to deliver extra power to electric thrusters during orbit raising, it could shorten this period by as much as 33%. During the Phase I period of performance, a subsystem architecture was created that utilizes this BOL solar array power.The architecture includes a power converter and controller unit, enabling spacecraft to fully utilize available solar array power while maintaining compatibility with existing components and interfaces.The Phase II program will further mature the power converter developed during Phase I; optimize the central controller concept developed during Phase I; construct prototypes of the power converter and central controller with form, fit, & function representative of a flight article; and perform ambient and environmental testing of the assemblies.