Evaluation and testing of the Naval Postgraduate School Satellite (NPSAT1) Solar Cell Measurement System

Abstract

The Naval Postgraduate School Spacecraft Architecture and Technology Demonstration Satellite, NPSAT1, launching in the fall of 2006, will include a system to measure the performance of new experimental triplejunction solar cells. The measuring circuit in the Solar Cell Measurement System (SMS) is based on a circuit developed at the Naval Postgraduate School many years ago. It will trace the cells' current-voltage (I-V) curves while in orbit. The SMS consists of a radiation-hardened microcontroller that uses a radiation-hardened FPGA to monitor a collection of sensors. A current-sink circuit is used to measure the current and voltage on the test cells. Prior to launch, extensive testing is being performed on the system to ensure proper operation. The tests consist of subjecting solar cells and the measuring circuit electronics under conditions modeling the space environment while taking cell measurements. This thesis presents the mission information, system design, test setup, and test results of the SMS measuring circuit.