Improvement of PMa-SynRM Output Characteristics by Optimizing the Rib Structure

Abstract

In this paper, we have studied the optimization of the rib thickness in the design of a Permanent Magnet assisted Synchronous Reluctance Motor (PMa-SynRM). In the case of PMa;-SynRM, mechanical stress is concentrated on the rib structure supporting the segment at high rotation speeds, and the stiffness analysis results in the largest mechanical stress on the rib of the q-axis. On the other hand, it was confirmed that relatively low mechanical stresses were distributed in the case of the d-axis rib. Therefore, it is confirmed that the thickness of the whole rib should be equal to the thickness that can support the maximum stress. In addition, we find that it increases the magnetic flux leakage and is an inappropriate design method for reducing the output power. To prevent this phenomenon, concentrations of mechanical stress on each of the ribs were investigated, and a method was developed for designing the ribs with the optimized rib thickness. In addition, the thickness of the ribs that satisfies both the electromagnetic output and the mechanical safety factor was derived using the response surface method. Finally, we confirmed the improvement of the output using FEM analysis.