High-Speed Permanent Magnet Synchronous Machine for Short-Term Operation in an Electrically Powered High-Lift System

Abstract

The noise footprint of aircraft at airports is one of the major reasons, why many of these facilities are located on the outskirts of cities instead of near the city centre. One approach to reduce this footprint is to increase the lift coefficient by using electrically powered high-lift systems (EPHLS) which are located near each wing's flaps. Each system consists of a turbo compressor which is directly driven by a permanent magnet synchronous machine at a maximum rotational speed of 60,000 rpm and a maximum required power of 80 kW. Current investigations focus on the enhancement of the aircraft's take-off and landing which limit the operating time of the EPHLS to a maximum of 240 s. This paper will highlight the design of the three main components of the EPHLS, namely SiC converter, electrical machine, and turbo compressor. The machine design is significantly influenced by the short operating time, thus moving the critical thermal parameters to the transient regime of the temperature characteristics. The thermal parameters for this machine design will be discussed and iterated for several scaled power levels, as the EPHLS consists of several turbo compressors along the wing span with different ratings. These are thermally characterized and compared to conclude what the scaling of electrical machines for short-term operation means for the thermal characteristic parameters. In the end, a different reference design point for the electrical machine is identified, a fast and simple way for the scaling of electrical machine designs for short-term operation with respect to power is found and conclusions for the design and scaling of combined power electronics, electrical machine, and turbo compressor systems are drawn.