Design of a CubeSat thermal control system for battery module

Abstract

One of the most critical nanosatellite sub-systems is the energy power system. Batteries included in it are subject to a significant temperature effect. Therefore, in order to increase the efficiency of the energy power system and increase the service life of the batteries, it is necessary to use a thermal control system. The paper proposes an approach to designing a system for ensuring the thermal regime of a nanosatellite battery module. The approach consists of two stages. At the first stage, a series of thermal vacuum tests of the system is carried out. As part of the tests, the thermodynamic properties of the elements of the energy supply system (specific heat capacity and thermal conductivity) are evaluated. The evaluation is based on the results of processing samples of temperature measurements of individual elements of the system. The criterion for matching the obtained solution is the value of the emissivity of the components. At the second stage, the cooling of the battery pack during the flight of the nanosatellite in the shadow part of the orbit is estimated. The evaluation takes into account the experimental values of the thermodynamic values of the components of the system. Thus, an estimate was made «from above» of the radiated power of the energy power system. On the basis of experimental and calculated data, the adequacy of the selected power of the battery block heater was assessed. The article provides an experimental development of the proposed approach, the mathematical models used and equivalent schemes for heat simulation of the battery module.

Keywords

• nanosatellite
• cubesat
• thermal model
• control system
• on-board system