Analysis of Torque Ripple and Cogging Torque Reduction and Vibration Characteristics by Changing Permanent Magnet Shape of 5 kW SPM Type Generator

In this paper, the characteristics of the electromagnetic field using FEM are analyzed for the PMSG basic model, and the optimized design is performed to improve the performance of the generator. In the case of the SPM type 5 kW generator used in this paper, the torque ripple level was analyzed to be relatively high compared with the load torque generated during operation. Therefore, shape design was performed to reduce it, and permanent magnet shape was selected as design variables. Particularly, the characteristics of permanent magnet attached to the rotor surface by segment type and magnet tapering were compared. As a result, reduction in torque ripple and cogging torque was confirmed through the design of the shape of the permanent magnet. Also, the influence of the change of torque ripple and cogging torque on the vibration characteristics was studied. The vibration characteristics of the basic model and the improvement model were compared and analyzed based on the electromagnetic characteristics data. Simulation data shows that the amplitude of vibration is reduced in the improved model.