This thesis describes the development of an Electrical Power System (EPS) prototype for the CubeSTAR nanosatellite. Without a power system the other subsystems on the satellite cannot function, therefore a continuous and reliable power source is needed.
CubeSTAR's triple-junction solar cells are characterized and a general introduction to spacecraft EPS is given. A solar simulator circuit that mimics the solar cell behavior is also described. The energy storage cells, which are Lithium Iron Phosphate based, are tested under various conditions. The proposed system employs two redundant and digitally controlled maximum power point trackers. To raise the efficiency of this low-voltage system, synchronous buck converters are used. A PCB implementation that fits into the pre-defined CubeSTAR structure is also presented.