Testing of a Power Management Module for Modular Satellites

Avionics for satellites is a market which is continuously expanding in the recent years,
especially due to the availability of low cost launch vectors. The reduction of the cost allowed
many institutions and universities to develop their own satellites. The Politecnico di Torino has
also followed this trend in the early 2000 and developed its own satellite which is called
PiCPoT (Piccolo Cubo del Politecnico di Torino). The main purpose of PiCPoT is to test
commercial components (COTS) in space and collect scientific data for research.
After that, Politecnico di Torino starts a further step on cube satellite research field. The new
project is called AraMiS which is the Italian acronym for Modular Architecture for Satellites.
The project wants to go beyond the CubeSat concept and create a true modular architecture,
particularly in the electronic subsystem. The satellite can use as many basic modules as
necessary to achieve the mission tasks. Therefore, the AraMiS architecture will lead to an
effective cost sharing between different missions since the same module design is adopted in
several satellites.
The ARAMIS project aims to achieve a reconfigurable modular satellite, in which each module
is designed in a way independent from each other, but at the same time, they can work with
other modules of the same type or different, to increase the overall system performance.
The subject of this thesis is to test a power management module of a modular satellite. In
Chapter 1, it gives a basic idea of general module architecture, the integrated subsystems and
module interfaces. In Chapter 2, the several individual blocks of the module of the modular
satellite are introduced theoretically, some of them are the voltage and current sensors, the
regulators and the MPPT. Also some simulation problems founded during the test were
explained, the modifications of the schematic were exposed and some future improvements are
introduced. Chapter 3 is focused on the solar cell, the first point is a study of the simulation
model of the solar cell, the second explains the procedure of fabrication the physical model and
its test and finally, the last points, expose the characterization of the solar cell.
After that, in Chapter 4 the individual block simulations were done to check the expected
behavior, once achieved, after get all simulation models, the entire power management system
simulation was done. To end the chapter, the ripple of the regulators was exposed. In Chapter 5,
the power management honeycomb board was tested, giving importance at regulators and the
PDB, several tables with data about the operational ranges regarding to the input and output
voltage and current were included. The temperature of the components was measured and some
photos took with the thermal camera were included. To end the chapter, the real ripple of the
regulators and the MPPT was compared with the theoretical.
The Chapter 6 is a comparison between the Chapter 4 and 5, contrasting the simulation signals
with the real measurements. The real voltage and current ranges of the regulators are compared
with the datasheet of the components.
To give a conclusion, the last chapter concludes what has been done in this thesis work and
proposes future works in order to improve the functional testing system described in this thesis.