Study of pyrolitic graphite sheet potential as thermal passive element in CubeSats

Abstract

CubeSats have become in the last decade ideal platforms to demonstrate new technology or to facilitate access to space due to the reduction in development time and costs. However, one of the main problems is the short lifetime of their missions. In many cases, it is due to the lack of correct thermal design and thermal analysis or even no thermal analysis at all. Specifically, the solar panel thermal design affects the global satellite behavior as the electric power supplied by the solar cells depends on their temperature. Typically, the solar panel thermal design is reduced to use its backside as a radiator (if they are deployable). This paper presents a new thermal solar panel assembly using an intermediate layer of PGS (Pyrolitic Graphite Sheet), which at room temperature has a thermal conductivity 3.8 times greater than pure copper, between the solar cells and the solar panel support, in order to homogenize the solar cells temperature. The new design is compared to the standard design developing the GMM (Geometrical Mathematical Model) and TMM (Thermal Mathematical Model) of a CubeSat 6U located in LEO using ESATAN-TMS. The proposed design gets a reduction of up to 5 °C in the temperature variation of the solar cells.