Deployable Thin Film Photovoltaic Array for Space Application: Designs and Evaluation

Abstract

Deployable Thin Film Photovoltaic Array for Space Applications: Designs and EvaluationBe it commercial satellites in a low earth orbit, or research satellites in deep space, overall, a trend towards higher energy requirements, that can no longer be effectively covered by conventional technology, is perceived.In order to achieve a higher energy density, the GoSolAr project (Gossamer Solar Arrays) of theGerman Aerospace Center(headed by the Institute ofSpace Systems in Bremen) relies on the use of thin film photovoltaics. In combination with other gossamermaterials, a flexible solar array is obtained, which is able to generatethe necessary energy despite its low mass and stowagevolume.Regarding the mechanical implementation of the solar array, new design options, inspired by the current state of the art, shall be developed and added to the existing poolof design options within this bachelor thesis.The focus primarilylieson the critical phase of deployment and thestowage of the solar array blanket, which is necessary for the transportto space.The three design parameters to be examined are the position ofthe,for the electrical connectionresponsible,harness, its folding, and structures to support the deployment.Since the different design options partially also influence each other across parameters, the best overall concept is to be determined with the help of a technical evaluation.Additionally, tests shall be done to gain a betterunderstanding ofthe design options in order to support the evaluation.The folding of the harness has proved to be the most important design parameter, as ithas a decisive influence on the deploymentprocess. Isolated deploymenttests of the individual design options revealed a folding concept that remains in stowed configurationwithout external influence as the most promising. This prevents the blanket from getting deployedby itself and uncontrollably so that the overall concept does not require any further structures to support thedeployment, by what its complexity gets reducedsignificantly.In a final step, this concept, which also performed best in the evaluation, was realizedas a breadboard model and underwentfirstsimple deployment tests, which proved that the deploymentwithout additional supporting structures was possible.