Session
Technical Session X: The Technology Frontier-- Advanced Technologies, Subsystems, and components for Small Satellites: Section I
Abstract
Rapid changes in semiconductor technologies over the last decade have spawned new interest in developing higher efficiency solar cells which are capable of using a broader part of the light spectrum. The Naval Postgraduate School’s NPSAT1, launching in the Spring of 2006, will include a subsystem which can be used to measure the performance of the new solar cells, providing an ability to combine functions previously available on only individual discrete components onto a single chip. The ability can help make space more accessible by reducing cost and complexity. The Solar Cell Measurement System (SMS) is a radiation hardened microcontroller based system using a radiation hardened FPGA that drives and monitors a collection of sun angle sensors, temperature sensors, a current sink/differential amplifier circuit combination for each of the 22 test cells and 2 control cells to be used in the experiment. The test cells are Triple Junction InGaP/GaAs/Ge cells and the control cells are Dual Junction cells. Triple Redundant Analog-to-Digital Converters, Digital-to-Analog Converters, and memory and interrupt logic will be implemented in the FPGA. The error budget developed for the circuits predicts a maximum error of 0.28%. The controller provides a common controller architecture for NPSAT1’s Electrical Power System and Attitude Control System. Future versions of the system will be able to further reduce costs by implementing a processor core into the FPGA.
Presentation Slides
Solar Cell Measurement System for NPS Spacecraft Architecture and Technology Demonstration Satellite, NPSAT1
Rapid changes in semiconductor technologies over the last decade have spawned new interest in developing higher efficiency solar cells which are capable of using a broader part of the light spectrum. The Naval Postgraduate School’s NPSAT1, launching in the Spring of 2006, will include a subsystem which can be used to measure the performance of the new solar cells, providing an ability to combine functions previously available on only individual discrete components onto a single chip. The ability can help make space more accessible by reducing cost and complexity. The Solar Cell Measurement System (SMS) is a radiation hardened microcontroller based system using a radiation hardened FPGA that drives and monitors a collection of sun angle sensors, temperature sensors, a current sink/differential amplifier circuit combination for each of the 22 test cells and 2 control cells to be used in the experiment. The test cells are Triple Junction InGaP/GaAs/Ge cells and the control cells are Dual Junction cells. Triple Redundant Analog-to-Digital Converters, Digital-to-Analog Converters, and memory and interrupt logic will be implemented in the FPGA. The error budget developed for the circuits predicts a maximum error of 0.28%. The controller provides a common controller architecture for NPSAT1’s Electrical Power System and Attitude Control System. Future versions of the system will be able to further reduce costs by implementing a processor core into the FPGA.
