Performance analysis of asymmetrical less‐rare‐earth permanent magnet motor for electric vehicle

Abstract

To reduce the manufacturing cost, the cogging torque and the torque ripple of the traditional V-shaped permanent magnet motor (TPMM), an asymmetrical less-rare-earth permanent magnet motor (ALREPMM) is proposed. An equivalent air-gap flux density model is established, the model is employed to calculate the analytical expression of the no-load back-EMF, and the multiple objectives optimisation are carried out for the motor parameters based on the Taguchi algorithm. Electromagnetic performance of the TPMM structure and the ALREPMM structure is compared by finite element method-based simulation. It is shown that the ALREPMM structure can reduce the amount of rareearth materials by 19%, and the cogging torque and the THD values of no-load back-EMF are reduced by 77.3% and 26.8%, respectively. Finally, a prototype is manufactured, thus verifying the rationality of the design of the ALREPMM structure through experiments.

Multi‐Objective Optimization and Analysis of Asymmetric Hybrid‐Magnet Offset Motor for Electric Vehicles

“…Due to the energy and environmental problems, traditional fuel vehicles are constantly changing to electric vehicles, and the automotive industry has a strong demand for electric vehicles, and the drive motor is one of the core components of electric vehicles, and a high-performance drive motor can maximize the driving performance and economic performance of electric vehicles [1][2][3][4]. Therefore, the use of high-efficiency motors is an important direction for the development of electric vehicles [5].…”

Simultaneous improvement of cogging torque and torque density in axial flux‐switching permanent magnet motor

“…The motor used in the electric vehicle must-have features such as efficiency, torque density, lightweight, low cost, and high reliability [1][2][3][4]. In this regard, some references such as [4,5] have gone to less rare earth pm motors to reduce the cost, while the use of this pm will reduce the density of the electromagnetic torque of the electric vehicle propulsion motor, which is not desirable.…”

“…The motor used in the electric vehicle must-have features such as efficiency, torque density, lightweight, low cost, and high reliability [1][2][3][4]. In this regard, some references such as [4,5] have gone to less rare earth pm motors to reduce the cost, while the use of this pm will reduce the density of the electromagnetic torque of the electric vehicle propulsion motor, which is not desirable. Axial Flux-Switching permanent magnet (PM) (AFSPM) motors have attracted attention due to their ability to focus high flux, good efficiency, better heat transfer, short axial length, compact structure, and lightweight compared to some radial flux machines [6,7].…”