Galileo Solar Arrays In-Orbit Performance Analysis and Power Prediction Using PEPS

Telemetry data from the Solar Arrays of nine satellites (4 IOV and 5 FOC) from the Galileo constellation have been analyzed for evaluating their performance and for making power predictions. A set of dedicated tools has been developed to perform the telemetry data analysis, while ESA's tool PEPS (Platform for Energy and Power Simulation) has been used to perform all the simulations. Solar array current and rear side panels temperature were the available parameters to monitor the Solar Array's in-orbit performance. The analysis tools proved to be very useful to detect at first glance the degradation trend over the years and possible anomalous behaviors. PEPS model simulation, validated with the design EOL (End of Life) figures, allowed to fit the telemetry data and to highlight both the adequacy of the design and to confirm the margin in power (for all nine Solar Arrays) at the end of nominal mission duration even considering the worst case scenario.