ESEO Power System

The ESEO (European Student Earth Orbiter) spacecraft is a microsatellite platform launched on 3rd of December 2018, on board the Spaceflight's SSO-A (SmallSat Express), the dedicated rideshare mission from the Vandenberg Air Force Base in California (US). ESEO is part of ESA Academy's hands-on space programme designed to provide university students across Europe with the unique opportunity to gain significant practical experience in the design, development, launch and operations of a real space project. The Prime Industrial contractor, SITAEL, developed the satellite platform, performed the assembly integration and testing of the whole spacecraft, including the integration of the student-built payload and subsystems, and provided technical support to the student teams under ESA's coordination. The ESEO mission has a special value for the industry involved, since it validates in-orbit the SITAEL S-50 platform (50 kg including the payload), the smallest within the SITAEL products portfolio, representing a crucial milestone of the intensive work in designing, developing and manufacturing innovative multipurpose small satellites platforms. The Power System (PS) design has taken the advantage of a fruitful collaboration with the Budapest University of Technology and Economics (BME), who was in charge of the Power Distribution Unit (PDU), and with ESA as program coordinator who made available its experts. The PS design guidelines have been the reliability maximization in all platform modes and the single failure tolerance, with the overall cost reduction always in mind. Further, the reduced volume and size of this micro-platform represented an additional challenge to designers. The achievement of these objectives has been obtained thanks to the union of proven space solutions, adopted in many ESA missions, and the selection of industrial or military grade components with space heritage. After a brief overview of the ESEO mission, the focus will be moved to the PS architecture description, redundancies strategy and design approaches.