A Flexible Autonomous Power Management System for Small Spacecraft

Small satellites have used a variety of methods for regulating battery charge and managing solar power variations, mainly adapted from standard practice on larger spacecraft. A computer controlled power management subsystem is described with advantages for small spacecraft. Small spacecraft must be more parsimonious with power because of mass and surface area limitations. The controller provides separate modes for dealing with this scarce resource in load-limited, solar array-limited and battery-limited regimes. A microcontroller implements the strategies chosen for each regime, and is capable of fully autonomous operation. Algorithms have been developed to allow this controller to implement a self-adjusting digital servo system which continuously seeks to optimize operation. Theory, implementation and results will be presented