Mechanical design of high frequency, high power density electric machine

High power density motor;high specific power motor;high speed motor;mechanical design;turbo-electric.

Chen, Yuanshan ; Haran ; Kiruba S.

关键词: High power density motor;    high specific power motor;    high speed motor;    mechanical design;    turbo-electric.;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/92836/CHEN-THESIS-2016.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

In recent years, electric vehicles have demonstrated great economic and environmental advantages in the transportation industry due to the advance of battery and power converter technologies. However, large-scale commercial aircraft electrification is hindered by the technology gap of electric machines. This thesis presented a high frequency, high power density (> 13 kW/kg), MW level electric motor design for the application to augment the power of turbo engines on future 737 class hybrid-electric aircrafts.The thesis will focus on the mechanical design for the innovative motor architecture, in order to facilitate an interdisciplinary design optimization. A permanent magnet type motor with inside-out configuration was chosen because of its advantage of high peak efficiency and compactness in combination of state-of-the-art materials and technologies, such as Halbach array magnets and airgap windings. Combining these novel ideas imposed challenges onto the mechanical design of the motor, mainly because the design was optimized to thin radial builds for weight reduction, while the motor structural integrity needed to be assured for its high speed operation. The works presented in this thesis will aim to tackle the critical mechanical challenges for a proposed motor design. The challenge for static structural deformation includes the rotor radial expansion at high rotational speed, and the static deflection of external rotor due to the effect of gravity. The thin radial builds of the design with high frequency operation also made the motor subject to vibration challenge. Resonant vibration modes analysis was done to both the stator and rotor. In all the studies mentioned, the design challenges were first expressed by analytical calculations, and then confirmed by high fidelity finite element analysis. The mechanical design would mitigate the risks of failure while providing interdisciplinary design insight to achieve an overall high power density for the motor.