Estimation of Online Power Behavior in PHOENIX’s Electrical Power Subsystem

Research in space technology and small satellite development is getting more prosperous in recent year. The 2U CubeSat PHOENIX is developed at NCKU as a part of the QB50 mission, which will be launched in 2017. PHOENIX consists of several subsystems and one of the most critical one is the Electrical Power Subsystem (EPS), which provides, stores, distribute and controls the satellite’s electrical power. Prior to execute any mission, it is necessary to ensure that the power margin is sufficient. The paper provides a power system model to predict the online power behavior to avoid overloading. The purpose of the power system model is to maximize the mission performance and to prevent the CubeSat from entering the safe mode repeatedly, which interrupts the scientific mission operation. As a case study, the QB50p1 and QB50p2 of QB50 precursors, which are currently in orbit, are used in the analysis. The model is built up and verified based on the simulation software, PHOENIX’s data, and QB50 precursors’ data.