Modelling of stress development in high pre-load filament banding of high-speed rotors for PMSM applications

Increasing the permissible operating speed of permanent magnet electric machines (PMSM) presents a range of intrinsic benefits. This however also raises a myriad of challenges associated with high-speed operation, including rotor burst. One solution is the use of filament wound rotor sleeves. The present work brings to attention the importance of understanding the rotor and band stress state in filament banded rotors. An analytical model was developed which captures the effects of winding tension and rotor stiffness. This model will be experimentally validated through in-situ stress measurement during filament winding. A basic optimisation approach for the parameters of winding tension and layer count are proposed, which result in an increase in the maximum operating speed without altering the sleeve material or geometry. This type of modelling which considers the interaction between banding configuration and rotor geometry can be further extended to describe complex rotor stack-up and non-uniform stress development.