High-performance electric machines will require new rotors with improved mechanical properties. Carbon fibre-reinforced polymer (CFRP) shafts have the potential to increase the bearing distance and widen the laminated core, resulting in increased engine power. However, the low thermal conductivity of CFRP presents a significant obstacle to heat dissipation from the electromagnetically active part on the outside to the cooled inside of the rotor shaft. A new hybrid design of carbon fibre composite rotor shafts with improved thermal conductivity in the thickness direction enables such machines.
This paper describes the comprehensive design and selection process used to determine a preferred variant. The investigation involves multiple design iterations and analyses. A systematic approach, combining theoretical models and analytical calculations, is used to compare and evaluate different cooling strategies, structural configurations, and material combinations.
The paper results in the new hybrid design of the preferred variant for use in the electric machine, which