Abstract
Axial flux permanent-magnet synchronous machines (PMSMs) are very suitable candidates for the power train of electric vehicles (EVs) due to high power density and high efficiency. This paper researches an axial flux PMSM with radially sliding permanent magnets (PMs) to fulfill field-weakening control. The field weakening principle and the structure of this kind of axial flux PMSM by mechanical method of sliding PMs are proposed and analyzed. The influences of radially sliding PMs on magnetic flux density distribution, inductance, flux linkage and torque are analyzed and discussed based on 3D finite element method (FEM). The field weakening capabilities by mechanical method and electrical method are compared. The field weakening capability of the machine can be much improved by the optimized combination of the two methods, which is very satisfying for EV drive application. The forces on the PMs are analyzed and calculated. The hysteretic characteristics caused by the friction of the PMs are investigated, which provide useful reference for designing this kind of machine.
Highlights
With the problems of air pollution and energy consumption getting more and more concerns, the traditional vehicles with internal combustion engine (ICE) will be probably eliminated in future transportation because they consume fuel derived from non-renewable resources and release exhaust gas
Considering the speed requirement for the machine used for electric vehicles (EVs), the axial flux permanent-magnet synchronous machines (PMSMs) with radially sliding permanent magnets (PMs) adopting mechanical device similar to the structure described in [29] will be investigated comprehensively in this paper
With the PMs sliding outward, the saturation in normal case decreasing to unsaturation, the inductances in normal case is close to inductances in unsaturated case, which validates that the saturation dose has much effect on the inductances of the machine with sliding PMs
Summary
With the problems of air pollution and energy consumption getting more and more concerns, the traditional vehicles with internal combustion engine (ICE) will be probably eliminated in future transportation because they consume fuel derived from non-renewable resources and release exhaust gas. Because of the disk structure of axial flux PMSM, most axial flux machines adopt surface-mounted permanent magnets (PMs) and have large air gaps, which result in small d- and q-axis inductances. This makes the field weakening more difficult to execute for wide range operation by using traditional electrical methods. Considering the speed requirement for the machine used for EVs, the axial flux PMSM with radially sliding PMs adopting mechanical device similar to the structure described in [29] will be investigated comprehensively in this paper. The forces on the PMs are researched and the hysteretic characteristics caused by the friction of the PMs are investigated
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
