Analytical modelling and sizing of supercapacitors for spacecraft hybrid energy storage systems

• Published in: Acta astronautica 2023-10, Vol.211, p.382-392
• Main Authors: Marín-Coca, S., Roibás-Millán, E., Pindado, S.
• Format: Article
• Language: English
• Subjects: Hybrid; Li-ion; Modelling; Power; Sizing; Supercapacitor
• ISSN: 0094-5765; 1879-2030
• DOI: 10.1016/j.actaastro.2023.06.041

The vast majority of Earth-orbiting satellites carry an electrical power subsystem (EPS) which main components are solar panels and secondary batteries. During eclipse periods, satellites are powered only by rechargeable batteries which have a large energy density but a limited power density. This fact limits the power capabilities of small satellites during eclipse periods. Due to the large power density of Supercapacitors (SCs), ground and on-orbit tests have been conducted to verify their applicability on satellite EPSs. At the moment, no studies are underway on the issue of sizing SCs for eclipse operations. Hybrid configuration could reduce the mass and volume of EPS or maintain those reference values but increasing peak power capabilities. This paper deals with this issue. On the one hand, novel analytical expressions of a variable capacitance SCs are derived, including time–voltage dependence in constant power applications. Also an equivalent formulation for a SCs bank (SCsB) is derived. On the other hand, a SCsB sizing procedure is presented, considering the energy and power requirements of a particular space mission as an input. Finally, a simple mission is analysed, the results showing an improvement on the hybrid EPS design with respect to the traditional, being the mass reduction of 36%. •Implementation of a simple but accurate supercapacitor (SC) model for spacecraft applications.•Innovative analytical expressions of the performance of a SC in constant power applications.•Novel determination of the electrical parameters of a SCs bank, treated as an equivalent SC model.•Estimation of key variables in the operation of hybrid storage systems for space applications.•Preliminary design of a SCs bank devoted to supply high power during eclipse times.