A NEW ELECTRICAL POWER SYSTEM ARCHITECTURE FOR DELFI-PQ

Due to strict constraint regarding the volume of a PocketQube (50x50x50 mm) it is crucial to reduce the space that is consumed by the satellite bus subsystems. This paper focuses on a new architecture for the electrical subsystem in order to reduce its volume and increase the usage of empty surfaces inside the satellite. This increment in volume efficiency is going to be achieved by splitting the electrical power system on different surfaces and reducing the number of required voltage regulators. This modular approach is going to be realized by two main steps. First, removing the regulated bus from the satellite and delivering an unregulated bus to the subsystems. This will also give flexibility to other subsystems to use a voltage level which are more suitable for their requirements. Secondly, the internal side of the solar panels are going to be used for MPPT (maximum power point tracking) circuits, actually achieving a distributed power generation system, similar to ground-based solar power generation systems. The battery board is going to be a separate board with its dedicated communication lines and will also act as an interface between the solar panels and power distribution board via simple spring loaded connectors. This latter solution helps reducing dramatically the number of cables in the satellite, thus simplifying integration. The main objective of this work is turning the EPS(electrical power system) into a more flexible, scalable and volume-efficient system by a physical relocation of its components and a lean approach. The new EPS will be functionally and environmentally tested in a flight representative satellite model with the aim to verify its simplification in integration, assess its true performance as well as its reliability during launch vibration which especially includes spring-loaded connectors.