Cabin air compressor cooling system

摘要

A closed loop cooling system and method for an oil-free electric motor of an aircraft cabin air compressor. A closed-loop fan, which may be coupled to a motor rotor opposite a compressor impeller, circulates the required cooling air in a closed loop through a motor stator and bearings, a motor cooler, and a ducting used to complete the flow circuit via a ram air cooled heat exchanger. The cooling air may be pressurized to cabin pressure. The system and method of the present invention eliminates the possibility of contaminating trace amounts of oil in cabin supply air.