Aerospace power control system for monitoring and reliably transferring

Abstract

An aerospace power control system switches an aerospace load from a faulty ac power bus to a good ac power bus of two or more ac power buses if the currently connected ac power bus is about to fail. The voltage level and frequency of the power provided on the buses are monitored to determine which of the power buses are within required limits to provide power to the aerospace load. If monitoring of the currently connected ac power bus indicates that the bus is not within the required limits and may be shut down in the immediate future, the connection of the aerospace load is switched to another ac power bus which is within the required limits. The current provided to the load is monitored to determine zero-crossing points of the current with the switch from the currently connected faulty bus to a good bus being performed at a zero-crossing point of the load current. The level of the current being provided to the aerospace load is also monitored to detect a faulty load condition. If the load current exceeds defined limits, the load will be disconnected from all ac power buses to shut down the faulty load. The aerospace power control system is generally applicable to single phase and three phase ac power, with switch over at zero-crossing points being performed on a phase-by-phase basis for three phase ac power.