Hybrid optimization-expert system for the allocation of loads on board a large space station.

摘要

A load scheduling tool using hybrid optimization-expert system techniques was developed. This tool is to be integrated with the Power Management and Distribution system of the Space Station Freedom. The Space Station is designed to be powered using Photo-Voltaic system, the output power of the PV system is limited and constrained. The constraints are on the battery performance and the sizing of solar cells arrays. The proposed scheme allocates the loads by using rule-based approach for optimizing the energy available on board the space station.; The scheme is divided into two processes, namely an off-line expert system to perform a heuristic optimization search that will maximize the use of energy. The second process or phase is the rescheduling process which is an on-line phase uses the same approach in phase one together with minimization of disturbance of the schedule for given contingency. This rescheduling process uses a real time measurement of the power system.; The overall scheme was implemented in-house using PROLOG. It consists of five different modules: dynamic database, interface, schedule, reschedule, and mode analyzer. The scheme is tested using the expected operations of the Space Station Freedom. Comparing the approach with classical optimization techniques, the heuristic optimization approach produces a schedule that utilizes the maximum energy available with minimum error and faster scheduling time. The scheme is able to handle three contingencies by using the rescheduling process. Similarly the system was able to minimize the disturbance of the schedule.