Design and on-orbit testing of a CubeSat modular electric power system
[Objective]CubeSats have become increasingly popular in space science exploration,earth observation,new technology verification,education,and other fields.Although their complexity and practicality have been significantly improved,the capacity and expansion capability of conventional CubeSat electric power systems(EPSs)often fall short for applications such as remote sensing and communication.Customizing the EPS of large satellites to specific missions is not feasible for low-cost,rapidly integrated CubeSats.This study proposes a modular power system design and development method to reduce the coupling between the EPS and satellite platform,thereby enhancing mission adaptability and rapid integration for future CubeSats.[Methods]This study comprehensively discusses the typical characteristics of the CubeSat platform and EPS under complex mission requirements.The proposed EPS adopts a unified structure,information,and power interface for loose coupling with the satellite platform.Standardized module units are designed to form"basic block components,"allowing flexible expansion of power capacity and distribution channels through module configuration and stacking structures.Based on the energy balance calculations,technical specifications for solar arrays,battery packs,and power controllers are proposed.The rapid integration of these three major parts of the EPS is achieved through the construction of basic block components,so as to quickly meet the power needs of CubeSats for diverse tasks.[Results]The overall architecture of the modular power system is proposed,and modular designs for the solar array,battery pack,and power controller are developed separately.1)For the solar array,the principle of a strong constraint on the total power and a weak constraint on the configuration form was proposed.The output voltage of a single solar array string can reach 40 V with a current of 4 A.2)The battery pack is designed with two specifications(7.2 V and 14.4 V)and standard interfaces,while the capacity can be easily expanded by PCB stacking.3)Based on the modular design of maximum power point tracking,the power controller can handle total power exceeding 100 W and has a configurable number of input and output channels.4)As a case study,the 6U CubeSat BY-03 was used to verify and realize the modular EPS design method.The development time of the EPS was less than two months,achieving energy balance within one orbit,with all modules functioning well in orbit and meeting the primary design requirements.[Conclusions]This study demonstrates the rapid design and integration of CubeSat EPS based on a modularity method.The designed EPS features a flexible configuration for power capacity and distribution channels,which quickly meets the power supply requirements of CubeSats with diverse tasks.An analysis of the on-orbit telemetry data from the BY-03 satellite confirmed the effectiveness of the proposed method.The designed EPS can be widely adopted in engineering applications for scientific and remote sensing CubeSats,and its power requirements can reach hundreds of watts.
CubeSatmodular designelectric power systemon-orbit validation