Permanent-Magnet Optimization in Permanent-Magnet-Assisted Synchronous Reluctance Motor for a Wide Constant-Power Speed Range

Abstract

A permanent-magnet (PM)-assisted synchronous reluctance (PMASR) machine exhibits both high efficiency and high flux-weakening (FW) range. However, the best performance is achieved after a machine design optimization. In industry applications, the design of PMASR machines requires to satisfy an increasing number of limitations. The key points are lamination geometry, material property, and control strategy. This paper analyzes the influence of PM volume (flux level) on the motor performance, although lamination geometry and stack length are kept fixed. Thus, the PM volume inset in the rotor is optimized. The considered PMASR motor is designed for a very high FW speed range. The study is based on a finite-element (FE) analysis. The accuracy of the FE simulations is verified comparing their results with measurements on a prototype. The FE model is then used to study the different cases

Optimized design of a high-power-density PM-assisted synchronous reluctance machine with ferrite magnets for electric vehicles

“…A synchronous reluctance machine (SynRM) is also a candidate for a rare-earth-free machine, but its torque density, power density, power factor and efficiency are inferior compared to PMSMs [14][15]. By adding the proper amount of PMs in SynRM, the torque density and power density of a PM-assisted SynRM (PMASynRM) can be improved [16][17][18][19][20][21][22][23][24][25][26][27][28]. The total costs of PMASynRM with ferrite magnets can be reduced because some rare-earth materials such as neodymium and dysprosium, needed for automotive applications are not used in this machine.…”

Design And Rotor Geometry Analysis Of Permanent Magnet–Assisted Synchronous Reluctance Machines Using Ferrite Magnet

“…On the other hand, in order to enhance and increase torque density of pure synchronous reluctance machines, the permanent magnet can be inserted into rotor lamination to contribute torque production, which is so-called permanent magnet-assisted synchronous reluctance machines (PMA-SynRM). It will be a good candidate for next generation electric vehicle traction applications [7][8][9].…”

Comparison of Two Rotor Configurations by Changing the Amount of Magnet and Reluctance Components

“…The effect of PM volume on the PMa-SynRM is analyzed in [18], although lamination geometry and stack length are kept fixed. The influence of the PM volume on the machine performance is highlighted by FE simulations and measurements [18].…”

“…The influence of the PM volume on the machine performance is highlighted by FE simulations and measurements [18].…”