Axial Flux PM In-Wheel Motor for Electric Vehicles: 3D Multiphysics Analysis

The Axial Flux Permanent Magnet (AFPM) motor represents a valid alternative to the traditional radial flux motor due to its compact structure; it is suitable for in-wheel applications so that the transmission gear can be suppressed. The modeling of the motor is a purely Three-Dimensional (3D) problem and the use of 3D finite element tools allows the attainment of accurate results taking also into account the effects of the end-windings. Moreover, a 3D multiphysics analysis is essential to evaluate not only the motor performance and its thermal behavior, but also the electromagnetic forces acting on the surfaces of the stator teeth and of the magnets that face the air gap. Moreover, as the vehicle’s motors often work in variable-speed conditions, the prediction of vibrations and noise for electric motors over a wide speed range is usually necessary. The paper presents a double-sided AFPM motor for a small pure electric vehicle; the basic drive architecture includes four axial flux motors installed directly inside the vehicle’s wheels. The aim is to propose advanced and integrated electromagnetic, vibroacoustic and thermal analyses that allow the investigation of the axial flux motor behavior in a detailed and exhaustive way.

Download Full-text

A comparison of torque capabilities of axial flux and radial flux type of brushless DC (BLDC) drives for wide speed range applications

Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475) ◽

10.1109/peds.1999.792793 ◽

1999 ◽

Cited By ~ 13

Author(s):

N. Balkan Simsir ◽

H. Bulent Ertan

Keyword(s):

Axial Flux ◽

Brushless Dc ◽

Radial Flux ◽

Speed Range ◽

Wide Speed Range

Download Full-text

Spillage-Adaptive Fixed-Geometry Bump Inlet of Wide Speed Range

Aerospace ◽

10.3390/aerospace8110340 ◽

2021 ◽

Vol 8 (11) ◽

pp. 340

Author(s):

Zonghan Yu ◽

Guoping Huang ◽

Ruilin Wang ◽

Omer Musa

Keyword(s):

Boundary Layer ◽

Design Method ◽

Three Dimensional ◽

Low Speed ◽

Flight Vehicles ◽

Integration Pattern ◽

Speed Range ◽

Flexible Integration ◽

Wide Speed Range ◽

Future Work

In this work, a new spillage-adaptive bump inlet concept is proposed to widen the speed range for hypersonic air-breathing flight vehicles. Various approaches to improve the inlet start-ability are summarized and compared, among which the bump-inlet pattern holds the merits of high lift-to-drag ratio, boundary layer diversion, and flexible integration ability. The proposed spillage-adaptive concept ensures the inlet starting performance by spilling extra mass flow away at low speed number conditions. The inlet presetting position is determined by synthetically evaluating the flow uniformity and the low-kinetic-energy fluid proportion. The numerical results show that the flow spillage of the inlet increases with the inflow speed decrease, which makes the inlet easier to start at low speed conditions (M 2.5–6.0). The effects of the boundary layer on spillage are also studied in this work. The new integration pattern releases the flow spillage potentials of three-dimensional inward-turning inlets by reasonably arranging the inlet compression on the bump surface. Future work will focus on the spillage-controllable design method.

Download Full-text

Investigation of Axial Flux In-Wheel Motor Performances Based on Multiphysics Analysis

E3S Web of Conferences ◽

10.1051/e3sconf/202123601019 ◽

2021 ◽

Vol 236 ◽

pp. 01019

Author(s):

Haishi DOU ◽

Youtong ZHANG ◽

Tao LI ◽

Qiang AI

Keyword(s):

Electric Vehicles ◽

Motor Performance ◽

Thermal Analyses ◽

High Power Density ◽

Thermal Coupling ◽

Axial Flux ◽

Compact Structure ◽

Torque Density ◽

Electromagnetic Loss ◽

Motor Structure

The axial flux with amorphous alloy stators has the virtues of high power density, high torque density, compact structure. But specific to the disadvantage of restricted space of in-wheel, the compact axial flux in-wheel motor was proposed in this paper. The in-wheel motor’s performance affects the dynamic and security of electric vehicles directly. And the electromagnetic loss has a significant impact on in-wheel motor performance. To demonstrate the influence of electromagnetic loss on the thermal behavior of the machine, thermal analyses employing magneto-thermal coupling simulations have been performed. Then the experimental prototype was manufactured and tested. The simulation of the output power model was verified by test value, proving that the magneto-thermal coupling simulation is feasible. Therefore, this design technique provides a reference for the in-wheel motor structure.

Download Full-text