A Study on Reducing Cogging Torque of Interior PM Motor for Electric Compressor

This paper proposes a new design of rotor shape of IPM motor used for electric air-conditioning system of HEV. The distribution of the residual magnetic flux density at the air gap is modified by rotor surface shape and V-type magnet angle. The finite-element method (FEM) is applied for the optimal shape design of rotor surface shape and V-type magnet angle, because the IPM motor has an extreme saturation in rotor core. The validity of the proposed rotor shape optimization is confirmed by the manufactured IPM rotor core and measured the performance of the cogging torque.