Investigation of the Effects of Skew of an Integrated Flux-Switching Motor-Compressor

Abstract

The integrated motor-compressor integrates a flux-switching permanent magnet (FSPM) machine with an axial-flow compressor by shaping the rotor poles of the motor into airfoils. The airfoil-shaped rotor functions as the rotor of a motor as well as the rotor of an axial-flow compressor. The airfoil-shaped rotor poles need to be skewed by the proper blade stagger angle to perform optimal thermodynamic performance with an optimal attack angle. The objective of this paper is to investigate the effects of the stagger angle of the airfoil-shaped rotor on the thermodynamic performance of the integrated motor-compressor with respect to the compression power, compressor stage efficiency, flow turn angle, and total pressure ratio by velocity triangles and mean line calculations. The effects of skew of the stator on the electromagnetic performance of the integrated motor-compressor in terms of winding factor, cogging torque, magnet losses, winding resistance, and iron losses are evaluated by analytical equations and 3-D finite element analysis (FEA).