High frequency GaN device-enabled CubeSat EPS with real-time scheduling

This paper describes the hardware and software architectures and experimental results of a flexible and scalable electric power system (EPS) for CubeSat applications. The EPS has the three flexible battery charging modules (FBCM) to charge the battery and the four flexible digital point of load (FDPOL) converters to drive loads. It uses the maximum power point tracking (MPPT) algorithm to maximize output power from the solar arrays along with the battery state of health and state of charge determination algorithms to determine the health of the Li-ion batteries. This paper also evaluates converter performance with GaN devices driven at high frequencies in order to reduce the size of the filter components and provide better control of the converters. Analysis of a sample load's transients and its voltage regulation, using a real-time operating system (RTOS), is also discussed briefly in this paper.