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Electric Machines and Power Electronics for More Electric Aircraft Abstract: The More Electric Aircraft (MEA) concept is being widely recognized as the future technology for the aerospace industry. There is significant interest from the airframers, suppliers, and the military to convert most (if not all) of the pneumatic and hydraulic systems in the aircraft to electric. MEA technologies are continually evolving, and there is lot of opportunity for improvement as systems continue to be refined and enhanced. This has been further reinforced by the successful application of Airbus 380 in commercial flights and testing of Boeing 787. The MEA architecture offers significant overall system benefits in reliability, improving fuel efficiency, and reducing emissions. On the other hand, MEA concept imposes increasing demands on the electrical power generation, conversion, and distribution. In addition, it has to be safe, reliable, efficient, and fault tolerant. This presentation reviews the architectures and advantages of More Electric Aircraft powered by gas turbine engines which have embedded electric machines attached to both the low pressure and high pressure shafts, in place of today's systems that use complex gearing to permit fitting of generators (plus engine starter, oil pumps, hydraulic pumps and fuel pump) on the outside of the engine. The types of electric machines, their key features, and the required power electronics for high reliability and fault tolerant operation will be discussed. The problems associated with high frequency switching and cooling aspects; and the use of AC vs. DC for power distribution: advantages and limitations will also be presented. The use of superconducting machines as proposed by NASA for their N+3 distributed propulsion system will be briefly reviewed. |