Electromagnetic Analysis of Interior Permanent Magnet Rotor with Dual and Single Layer Magnet Rotor

This paper proposes a dual layer (delta-shaped) interior permanent magnet rotor with concentrated winding stator for the air conditioner refrigeration compressor of hybrid and pure electric vehicles. The proposed concentrated winding stator design is better than the existing distributed winding stator in terms of the refrigeration vehicle compressor internal flow, light weight structure, and compact design with small end-turn height (thin). However, concentrated winding also has some disadvantages including additional harmonics and torque ripple due to partial saturation. Therefore, this study proposes a design process for a dual layer interior permanent magnet rotor in order to minimize the torque ripple and magnet volume using the finite element method (FEM). The FEM result is determined at the weighted optimum operating point of the electric compressor, and is compared with that of the existing distributed winding model.