Design and Management of Satellite Power Systems

Abstract

Abstract-Satellites are indispensable for broadcast, weather forecast, navigation, and many other applications, but their design entails a number of stringent requirements, such as limited space and weight, impossible/costly online repairs, severe radiation, and a wide range of temperature they have to withstand. These requirements can only be met by an effective, robust co-design of physical and computing (control) parts of each satellite, making them prototypical cyber-physical systems (CPSes). Of the various CPS issues related to satellites, this paper focuses on offline design and online management of satellite power systems. Specifically, we analyze and model unique characteristics of power supply and demand of a satellite, which are dictated by the periodicity of power generation from solar panels and the nonlinear behavior of rechargeable battery cells. Based on the understanding of these characteristics, we first propose how to find the best configuration (e.g., the number, the arrangement, and the type) of solar panels and battery cells at design time, such that all tasks can be executed without power shortage throughout the satellite's mission lifetime. Second, we propose how to manage power online so as to execute the highest QoS versions of tasks (thus yielding the most power-effective performance) without compromising the power-sufficiency guarantee under a given configuration. As a case study, we study cubic-shaped nanosatellites, which have been launched multiple times since 2004. We borrow their architecture, configuration and parameters, and demonstrate the effectiveness of our design and management of satellite power systems.

Comprehensive design and control methodology for DC‐powered satellite electrical subsystem based on PV and battery

“…If there is no more allowance in changing the loads without impacting the mission goal, a suitable control strategy is determined or a hybrid PV array configuration is selected where both body mounted and deployable panels are used to fulfill power needs of the satellite. The required energy from deployable section of PV array is calculated in (20) while the average power and the number of PV cells required for deployable PV array are given in (21), assuming that sun-tracking is used throughout suntime duration for deployable PV panels; where, P pvc is equal to P mpp as MPPT loss is already considered in the equation for E pv-req . (21) Mass and area of deployable PV array is given in (22) and (23).…”

“…In [19] energy balancing is used for the design and evaluation of different EPS elements. A number of optimization based designs has also been presented [20, 21]. Design of a converter is presented in [22] for CubeSats but it is for a specific topology.…”

“…Design of a converter is presented in [22] for CubeSats but it is for a specific topology. A method for the sizing of PV array and battery is presented in [20]. Additionally, the selection of cells type and possible arrangement are also outlined.…”

Spacecraft energy management using convex optimisation

“…More recently, online management of spacecraft power systems was investigated in [6]. In this setting, each task has several degrees of refinement (versions), requiring varying amounts of power.…”

An Integrated Thermal-Electrical Model for Simulations of Battery Behavior in CubeSats

“…On the other hand, the work of [7] studied the state of charge estimation for the battery of satellites, but the authors did not assess it considering typical transient irradiance and temperature profiles found in orbit. There are also papers in the literature concerning specifically the design and management of satellites' power systems (electrical models) [20][21][22][23][24][25]; however, they do not present any generalized method that CubeSat engineers can further develop in order to satisfy the mission constraints and requirements that they are focused on in that moment.…”