A Study on the Rotor Design of Line Start Synchronous Reluctance Motor for IE4 Efficiency and Improving Power Factor

As international regulations of motor efficiency are strengthened, the line-start synchronous reluctance motor (LS-SynRM) is being studied to improve the efficiency of the electrical motor in industrial applications. However, in industrial applications, the power factor is also an important performance index, but the LS-SynRM has poor power factor due to the saliency characteristic. In this paper, the rotor design of LS-SynRM is performed to improve the efficiency and power factor. First, the barrier design is performed to improve the efficiency and power factor using the response surface method (RSM). Second, the rotor slot design is performed according to the length of bar for synchronization. Lastly, the rib design is performed to satisfy the power factor and the mechanical reliability. The final model through the design process is analyzed using finite element analysis (FEA), and the objective performance is satisfied. To verify the FEA result, the final model is manufactured, and experiment is performed.