Testing solar panels for small-size satellites: the UPMSAT-2 mission

Abstract

At present, the development of small-size satellites by universities, companies and research institutions have become a usual practice, which is spread rapidly. In this kind of projects the cost play a significant role. One of the main points are the Assembly, Integration and Test (AIT) plans, which carries out an associated cost for simulating the environmental conditions. For instance, in the power subsystems test and, in particular in the solar panels testing, the irradiance and temperature conditions might be the optimum so the performances of the system are next to real operational conditions.
 To reproduce the environmental conditions in terms of irradiance, solar simulators are usually used, which carries an associated increase of cost for testing equipments. The aim of this paper is to present an alternative and unexpenssive way to perform the AIT plans on spacecraft power subsystems, from a testing campaign performed using outdoor clean-sky conditions and an isolation system to protect the panels. A post-process of the measured data is therefore needed, taking into account the conditions in which the test has been accomplished. The I-V characteristics obtained are compared with a theorical 1-diode/2-resistor equivalent electric circuit, achieving enough precision based solely in the manufacturer data.