Design of a Permanent Magnet-Assisted Synchronous Reluctance Motor Rotor with Low Torque Ripple

Permanent magnet synchronous motors (PMSMs) are widely used due to their high torque density and efficiency. However, these motors rely heavily on expensive rare-earth permanent magnets (PMs), leading to high costs. To address the issues of high torque ripple and cost in PMSMs, a hybrid excitation design combining neodymium iron boron (NdFeB) and ferrite PMs was proposed based on an existing PMSM prototype. A low-torque-ripple rotor configuration with mixed PM arrangement was investigated, and parametric modeling and optimization of the rotor structure were conducted using finite element analysis (FEA). Electromagnetic simulations were performed to compare peak torque, cogging torque, and no-load back electromotive force (EMF). Cost evaluation confirmed the superior performance and cost-effectiveness of the proposed motor compared to the original design.