Power Management for Space Advanced Life Support 2002-01-2527
Space power systems include power source, storage, and management subsystems. In current crewed spacecraft designs, solar cells are the power source, batteries provide storage, and the crew performs any required load scheduling. For future crewed planetary surface systems using Advanced Life Support, we assume that plants will be grown to produce much of the crew's food and that nuclear power will be employed. Battery storage is much more costly than nuclear power capacity and so is not likely to be provided. We investigate scheduling of power demands to reduce the required peak power generating capacity. The peak to average power ratio is a good measure of power capacity efficiency. We can easily schedule power demands to reduce the peak power below the potential maximum, but simple scheduling rules may not achieve the lowest possible peak to average power ratio. An initial power scheduling example is simple enough for a human to solve, but a more complex example with many intermittent load demands required automatic scheduling. Excess power is a free resource and should be used to gain any possible benefits.