Design and Analysis of Permanent Magnet Synchronous Machine with Stator Tooth Splicing Structure Using Grain Oriented Electrical Steel

High saturation flux density, high permeability and low specific core loss in the rolling direction (RD) are the characteristics of anisotropic soft magnetic materials. In order to meet the requirements of high torque density, high power density and high efficiency for the electric vehicle traction electric motor, the application of anisotropic silicon steel, i.e., grain oriented electrical steel (GOES) sheets in traction electric motor is investigated in this paper. Firstly, Ultra-thin anisotropic silicon steel sheets are selected based on the analysis of material properties and the reduction of eddy current losses in the core. Then, the performance of the tooth-yoke spliced PMSM, which is superior to the conventional non-grain-oriented electrical steel (NGOES) sheet PMSM in terms of torque and efficiency, is analyzed using the finite element method (FEM). And the design of experiment and analysis of the results proved that the circular splice pattern of the motor tooth was superior to the dovetail splice. Finally, a GOES PMSM is manufactured for verification. It is revealed that the measured current amplitude of the GOES PMSM is about 6.06% lower than that of the NGOES PMSM under the same geometric parameters and rated output torque. When the electric motor is operating, as the speed increases, the efficiency and torque of the GOES motor are higher than those of the NGOES PMSM throughout the motor's operating range.