Matching Items (2)
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Description
The space industry is rapidly expanding, and components are getting increasinglysmaller leading to the prominence of cubesats. Cubesats are satellites from about coffee mug size to cereal box size. The challenges of shortened timeline and smaller budgets for smaller spacecraft are also their biggest advantages. This benefits educational missions and industry missions a

The space industry is rapidly expanding, and components are getting increasinglysmaller leading to the prominence of cubesats. Cubesats are satellites from about coffee mug size to cereal box size. The challenges of shortened timeline and smaller budgets for smaller spacecraft are also their biggest advantages. This benefits educational missions and industry missions a like but can burden teams to be smaller or have less experience. Thermal analysis of cubesats is no exception to these burdens which is why this thesis has been written to provide a guide for conducting the thermal analysis of a cubesat using the Deployable Optical Receiver Aperture (DORA) mission as an example. Background on cubesats and their role in the space industry will be examined. The theoretical side of heat transfer necessary for conducting a thermal analysis will be explored. The DORA thermal analysis will then be conducted by constructing a thermal model in Thermal Desktop software from the ground up. Insight to assumptions for model construction to move accurately yet quickly will be detailed. Lastly, this fast and quick method will be compared to a standard finite element mesh model to show quality results can be achieved in significantly less time.
ContributorsAdkins, Matthew Thomas (Author) / Phelan, Patrick (Thesis advisor) / Jacobs, Danny (Thesis advisor) / Wang, Liping (Committee member) / Bowman, Judd (Committee member) / Arizona State University (Publisher)
Created2022
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Description
The efficiency of spacecraft’s solar cells reduces over the course of their operation. Traditionally, they are configured to extract maximum power at the end of their life and not have a system which dynamically extracts the maximum power over their entire life. This work demonstrates the benefit of dynamic re-configuration

The efficiency of spacecraft’s solar cells reduces over the course of their operation. Traditionally, they are configured to extract maximum power at the end of their life and not have a system which dynamically extracts the maximum power over their entire life. This work demonstrates the benefit of dynamic re-configuration of spacecraft’s solar arrays to access the full power available from the solar panels throughout their lifetime. This dynamic re-configuration is achieved using enhancement mode GaN devices as the switches due to their low Ron and small footprint.

This work discusses hardware Implementation challenges and a prototype board is designed using components-off-the-shelf (COTS) to study the behavior of photovoltaic (PV) panels with different configurations of switches between 5 PV cells. The measurement results from the board proves the feasibility of the idea, showing the power improvements of having the switch structure. The measurement results are used to simulate a 1kW satellite system and understand practical trade-offs of this idea in actual satellite power systems.

Additionally, this work also presents the implementation of CMOS controller integrated circuit (IC) in 0.18um technology. The CMOS controller IC includes switched-capacitor converters in open loop to provide the floating voltages required to drive the GaN switches. Each CMOS controller IC can drive 10 switches in series and parallel combination. Furthermore, the designed controller IC is expected to operate under 300MRad of total dose radiation, thus enabling the controller modules to be placed on the solar cell wings of the satellites.
ContributorsHeblikar, Anand N (Author) / Kitchen, Jennifer (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Ozev, Sule (Committee member) / Arizona State University (Publisher)
Created2019