The research on mechanical properties of direct drive high-speed permanent-magnet machine for compression

The high speed permanent-magnet (HSPM) machine is appropriate for high speed operation due to its simple structure and high power density. In order to avoid stress damage to rotor caused by the centrifugal force and thermal stress, the strength analysis is very important. The rotor should have enough stability to avoid spaning the critical speed of bending mode. In addition, the structural vibration associated characteristics between the parts and the whole machine needs to be studied. This paper introduces a kind of hybrid rotor with carbon/glass fibre sleeve and compressor impeller. The three ply composite rotor is deduced by the 3D finite element method (FEM) model. Design guidelines of the high speed interference fit rotor that offers theory base for optimal design was generalized. Finite element (FE) analysis is used to study structural vibration associated characteristics for a HSPM machine with 315 kW, 18000 rpm.