scholarly journals Optimal Design of a High-Speed Flux Reversal Motor with Bonded Rare-Earth Permanent Magnets

Mathematics ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 256
Author(s):  
Vladimir Prakht ◽  
Vladimir Dmitrievskii ◽  
Vadim Kazakbaev
Keyword(s):  
Rare Earth ◽  
Optimal Design ◽  
Eddy Current ◽  
High Speed ◽  
Permanent Magnets ◽  
Eddy Current Loss ◽  
Specific Power ◽  
Current Loss ◽  
Sintered Magnets ◽  
Flux Reversal

Single-phase flux reversal motors (FRMs) with sintered rare-earth permanent magnets on the stator for low-cost high-speed applications have a reliable rotor and a good specific power. However, to reduce eddy current loss, the sintered rare-earth magnets on the stator have to be segmented into several pieces and their cost increases with the number of magnet segments. An alternative to the sintered magnets can be bonded magnets, in which eddy current loss is almost absent. The remanence of bonded magnets is lower than that of sintered magnets, and they are prone to demagnetization. However, the cost of low-power motors with bonded magnets can be lower because of the simpler manufacturing technology and the lower material cost. This paper discusses various aspects of the optimal design of FRM with bonded magnets, applying the Nelder–Mead method. An objective function for optimizing an FRM with bonded magnets is designed to ensure the required efficiency, reduce torque oscillations, and prevent the bonded magnets from demagnetizing. As a result, it is shown that the FRM with bonded magnets has approximately the same efficiency as the FRM with sintered magnets. In addition, the peak-to-peak torque ripple is minimized and the minimal instantaneous torque is maximized.

Performance analysis of magnetic gear with Halbach array for high power and high speed

2020 ◽  
Vol 64 (1-4) ◽  
pp. 959-967
Author(s):  
Se-Yeong Kim ◽  
Tae-Woo Lee ◽  
Yon-Do Chun ◽  
Do-Kwan Hong
Keyword(s):  
Permanent Magnet ◽  
Eddy Current ◽  
High Power ◽  
High Speed ◽  
Torque Ripple ◽  
Eddy Current Loss ◽  
Element Analysis ◽  
Current Loss ◽  
Halbach Array ◽  
Magnetic Gear

In this study, we propose a non-contact 80 kW, 60,000 rpm coaxial magnetic gear (CMG) model for high speed and high power applications. Two models with the same power but different radial and axial sizes were optimized using response surface methodology. Both models employed a Halbach array to increase torque. Also, an edge fillet was applied to the radial magnetized permanent magnet to reduce torque ripple, and an axial gap was applied to the permanent magnet with a radial gap to reduce eddy current loss. The models were analyzed using 2-D and 3-D finite element analysis. The torque, torque ripple and eddy current loss were compared in both models according to the materials used, including Sm2Co17, NdFeBs (N42SH, N48SH). Also, the structural stability of the pole piece structure was investigated by forced vibration analysis. Critical speed results from rotordynamics analysis are also presented.

Numerical analysis of eddy current loss of high-speed axial magnetic drive spindle

2021 ◽  
Vol 21 (2) ◽  
pp. 119
Author(s):  
Xu Qiao ◽  
Yang Tao ◽  
He Yuchen ◽  
Mei Shunqi ◽  
Meng Fanhe ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Eddy Current ◽  
High Speed ◽  
Eddy Current Loss ◽  
Current Loss ◽  
Magnetic Drive

Wireless Power Efficiency and Quality in Metal Shaft Environment With Eddy Current Losses and Electromagnetic Interference

2016 ◽  
Author(s):  
Miaomiao Xu ◽  
Xiongzhu Bu ◽  
Zhangjie Tu
Keyword(s):  
Eddy Current ◽  
Power Supply ◽  
Electromagnetic Interference ◽  
High Speed ◽  
Electromagnetic Coupling ◽  
Transmission Efficiency ◽  
Eddy Current Loss ◽  
Wireless Power ◽  
Current Loss ◽  
Wireless Power Supply

Wireless power transmission efficiency and ripple interference attract more and more attention nowadays, but in some special metal environments the transmission efficiency of wireless power will be greatly influenced. In some practical engineering application, we need to use wireless energy to power the sensor on the high speed rotating parts. In order to improve the transmission efficiency and quality of the wireless power supply, researches are conducted to evaluate the eddy current loss and electromagnetic interference of wireless power in high-speed rotating component parameter test system. In this paper, electromagnetic coupling wireless power supply system is established as the transmission model. Then the analytical expressions of eddy current loss are derived by solving Maxwell’s equations, and after that the eddy current loss characteristics is analyzed by combining with the electromagnetic coupling model and eddy current losses model in metal medium. To verify the theoretical results, Maxwell electromagnetic field simulation software is used to analyze the characteristics of the eddy current. Finally, experiments are carried out to illustrate the effect of ferrite magnetic shielding material on the eddy current loss and the shielding effect on the external electromagnetic interference in the metal shaft environment.

scholarly journals Reducing Rotor Temperature Rise in Concentrated Winding Motor by Using Magnetic Powder Mixed Resin Ring

Energies ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 6721
Author(s):  
Mitsuhide Sato ◽  
Keigo Takazawa ◽  
Manabu Horiuchi ◽  
Ryoken Masuda ◽  
Ryo Yoshida ◽  
...  
Keyword(s):  
Eddy Current ◽  
Temperature Rise ◽  
High Speed ◽  
Eddy Current Loss ◽  
Magnetic Powder ◽  
Current Loss ◽  
Composite Ring ◽  
Spatial Harmonics ◽  
High Speed Rotation ◽  
Speed Rotation

The demand for high-speed servomotors is increasing, and minimal losses in both high-speed and high-torque regions are required. Copper loss reduction in permanent magnet motors can be achieved by configuring concentrated winding, but there are more spatial harmonics compared with distributed winding. At high-speed rotation, the eddy current loss of the rotor increases, and efficiency tends to decrease. Therefore, we propose a motor in which a composite ring made from resin material mixed with magnetic powder is mounted on the stator to suppress spatial harmonics. This paper describes three characteristic motor types, namely, open-slot motors, composite-ring motors, and closed-slot motors. Spatial harmonics are reduced significantly in composite-ring motors, and rotor eddy current loss is reduced by more than 50% compared with open-slot motors. Thermal analysis suggests that the saturation temperature rise value is reduced by more than 30 K. The use of a composite ring is effective in reducing magnet eddy current loss during high-speed rotation. Conversely, the torque characteristics in the closed-slot motor are greatly reduced as well as the efficiency. Magnetic circuits and simulations show that on electrical steel sheets with high relative permeability, the ring significantly reduces the torque flux passing through the stator, thus reducing the torque constant. To achieve reduced eddy current loss during high-speed rotation while ensuring torque characteristics with the composite ring, it is necessary to set the relative permeability and thickness of the composite ring according to motor specifications.

Sign in / Sign up

Export Citation Format

Share Document