Software de Simulación de Performances de Sistema de Paneles Solares en Microsatélite

Abstract

The use of increasingly power-consuming and complex On-Board systems in current microsatellites implies the adoption of bigger and rather sophisticated deployable solar cells arrays. Thus, it becames necesary a power system adecuated to these microsatellites design specifications wich must have also an optimun output ror ail probable orbital and attitude conditions during lifetime. This situation drove to the development and integration of a software package able to simulate the behavior of panels. also allowing oprimisation studies.
Based upon a candidate geometrical conliguration, solar cell technical specifications, constructive and orbital data and materials characteristics, geographical position and attitude time histories are generated.
Subsequently, the interaction with the space enviromental conditions is computed. in order to detennine illumination and radiation for each panel. For temperature calculation over the solar cells, interaction with COSMOS finite elements program was made, obtainig time histories of temperature for each attitude and position of the satellite. Applying the TRW descriptive model for solar cells. I-V curves are obtained for panel. Afterwards, active panels contribution to the power systems panels interconected is calculated, y compounding I-V curves according to a teorethicaI procedure experimentaly checked. Performances of entire sistem, describing time evolution of satellite attitude, panels' temperature and generated power are obtained for each point of the orbital path. By means of a statisical treatment of the obtained data, mean and deviation values of the thermical and electncal magnItudes are calculated. Once quantified the performances of complete SOIJI cell array configuration. the companson between other purposed sistem configuration is posible: eventually some improvements would be' Jone. Tests cases were made upon design and/or on development geometrical contigurations in order to draw the corresponding parameters evolution curves wich are characteristic of the attitude, angular speeds and power under several orbital hipothesis. Algoritrns and obtained results are exposed herein.