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An electrical power system for CubeSats

The advent of CubeSats has provided a platform for relatively low-budget programmes to realise space missions. In South Africa, Stellenbosch University and the Cape Peninsula University of Technology have impressive space programmes and have been involved in numerous successful satellite launches. A...

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Main Author: Sheard, Benjamin Charles De Villiers
Other Authors: Ginsberg, Samuel I
Format: Thesis
Language:English
Published: Department of Electrical Engineering 2016
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access_status_str Open Access
author Sheard, Benjamin Charles De Villiers
author2 Ginsberg, Samuel I
author_browse Ginsberg, Samuel I
Sheard, Benjamin Charles De Villiers
author_facet Ginsberg, Samuel I
Sheard, Benjamin Charles De Villiers
author_sort Sheard, Benjamin Charles De Villiers
collection Thesis
description The advent of CubeSats has provided a platform for relatively low-budget programmes to realise space missions. In South Africa, Stellenbosch University and the Cape Peninsula University of Technology have impressive space programmes and have been involved in numerous successful satellite launches. A number of CubeSat projects are currently in progress and commercial-grade Attitude Determination and Control Systems (ADCS), and communications modules, are being developed by the respective universities. The development of a CubeSat-compatible Electrical Power System remains absent, and would be beneficial to future satellite activity here in South Africa. In this thesis, some fundamental aspects of electronic design for space applications is looked at, including but not limited to radiation effects on MOSFET devices; this poses one of the greatest challenges to space-based power systems. To this extent, the different radiation-induced effects and their implications are looked at, and mitigation strategies are discussed. A review of current commercial modules is performed and their design and performance evaluated. A few shortcomings of current systems are noted and corresponding design changes are suggested; in some instances these changes add complexity, but they are shown to introduce appreciable system reliability. A single Li-Ion cell configuration is proposed that uses a 3.7 V nominal bus voltage. Individual battery charge regulation introduces minor inefficiencies, but allows isolation of cells from the pack in the case of cell failure or degradation. A further advantage is the possibility for multiple energy storage media on the same power bus, allowing for EPS-related technology demonstrations, with an assurance of minimum system capabilities. The design of each subsystem is discussed and its respective failure modes identified. A limited number of single points of failure are noted and the mitigation strategies taken are discussed. An initial hardware prototype is developed that is used to test and characterise system performance. Although a few minor modifications are needed, the overall system is shown to function as designed and the concepts used are proven.
format Thesis
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institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:36:03.318Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2016
publishDateRange 2016
publishDateSort 2016
publisher Department of Electrical Engineering
publisherStr Department of Electrical Engineering
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source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/20101 An electrical power system for CubeSats Sheard, Benjamin Charles De Villiers Ginsberg, Samuel I Electrical and Electronics Engineering The advent of CubeSats has provided a platform for relatively low-budget programmes to realise space missions. In South Africa, Stellenbosch University and the Cape Peninsula University of Technology have impressive space programmes and have been involved in numerous successful satellite launches. A number of CubeSat projects are currently in progress and commercial-grade Attitude Determination and Control Systems (ADCS), and communications modules, are being developed by the respective universities. The development of a CubeSat-compatible Electrical Power System remains absent, and would be beneficial to future satellite activity here in South Africa. In this thesis, some fundamental aspects of electronic design for space applications is looked at, including but not limited to radiation effects on MOSFET devices; this poses one of the greatest challenges to space-based power systems. To this extent, the different radiation-induced effects and their implications are looked at, and mitigation strategies are discussed. A review of current commercial modules is performed and their design and performance evaluated. A few shortcomings of current systems are noted and corresponding design changes are suggested; in some instances these changes add complexity, but they are shown to introduce appreciable system reliability. A single Li-Ion cell configuration is proposed that uses a 3.7 V nominal bus voltage. Individual battery charge regulation introduces minor inefficiencies, but allows isolation of cells from the pack in the case of cell failure or degradation. A further advantage is the possibility for multiple energy storage media on the same power bus, allowing for EPS-related technology demonstrations, with an assurance of minimum system capabilities. The design of each subsystem is discussed and its respective failure modes identified. A limited number of single points of failure are noted and the mitigation strategies taken are discussed. An initial hardware prototype is developed that is used to test and characterise system performance. Although a few minor modifications are needed, the overall system is shown to function as designed and the concepts used are proven. 2016-06-23T14:50:02Z 2016-06-23T14:50:02Z 2015 Master Thesis Masters MSc (Eng) http://hdl.handle.net/11427/20101 eng application/pdf Department of Electrical Engineering Faculty of Engineering and the Built Environment University of Cape Town
spellingShingle Electrical and Electronics Engineering
Sheard, Benjamin Charles De Villiers
An electrical power system for CubeSats
thesis_degree_str Master's
title An electrical power system for CubeSats
title_full An electrical power system for CubeSats
title_fullStr An electrical power system for CubeSats
title_full_unstemmed An electrical power system for CubeSats
title_short An electrical power system for CubeSats
title_sort electrical power system for cubesats
topic Electrical and Electronics Engineering
url http://hdl.handle.net/11427/20101
work_keys_str_mv AT sheardbenjamincharlesdevilliers anelectricalpowersystemforcubesats
AT sheardbenjamincharlesdevilliers electricalpowersystemforcubesats