scholarly journals Variable single-axis magnetic-field generator using permanent magnets

AIP Advances ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 115312 ◽  
Author(s):  
Oleg Tretiak ◽  
Peter Blümler ◽  
Lykourgos Bougas
2012 ◽  
Vol 152-154 ◽  
pp. 1698-1704 ◽  
Author(s):  
Wen Chang Lang ◽  
Bai Zhong Wu ◽  
Bin Gao

Based on the principle of the control of magnetic field on arc spot motion, a compact and multi-function magnetic field steered arc source has been designed in this paper. The rotating magnetic field generator driven by small DC motors or AC motors has been also equipped behind the base of the target materials of magnetic field steered arc source. The magnet yoke fixed on shaft will be driven by the motors so as to promote the rotation of permanent magnets which are rationally distributed on magnet yoke. The different distribution of permanent magnets will produce the rotating magnetic field with different configuration structures and then the purpose of multi-control mode can be achieved. Meanwhile, the dynamic rotating magnetic field with different configurations have been also produced in this design through employing the simple and compact arc source as well as the permanent magnet with different distributions in order to improve the discharge form of arc spots, control the trajectory of arc spots, improve the utilization of target materials and the uniformity of etching as well as reduce or inhibit the emission of large particles. At the same time, the high-quality film can be also prepared so as to realize the arc spot control with various forms in an arc source, satisfy the different demands and expand the application of arc ion plating.


2012 ◽  
Vol 721 ◽  
pp. 41-46 ◽  
Author(s):  
Yasushi Nakahata ◽  
Koji Yamada ◽  
Jiao Lian Luo ◽  
Hiroyasu Shimoji ◽  
Bartosz E. Borkowski ◽  
...  

M-Heff full curves up to 19T for the permanent magnets composed of Nd-Fe-B were very precisely observed by using specially designed magnetizer. The pulsed magnetic field directions were safely reversed with the same coil-end to ground side of coil positive and negative field directions. The coercivity enhancements were observed by 15% in high pulsed field applications.


Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2522
Author(s):  
Guangdou Liu ◽  
Shiqin Hou ◽  
Xingping Xu ◽  
Wensheng Xiao

In the linear and planar motors, the 1D Halbach magnet array is extensively used. The sinusoidal property of the magnetic field deteriorates by analyzing the magnetic field at a small air gap. Therefore, a new 1D Halbach magnet array is proposed, in which the permanent magnet with a curved surface is applied. Based on the superposition of principle and Fourier series, the magnetic flux density distribution is derived. The optimized curved surface is obtained and fitted by a polynomial. The sinusoidal magnetic field is verified by comparing it with the magnetic flux density of the finite element model. Through the analysis of different dimensions of the permanent magnet array, the optimization result has good applicability. The force ripple can be significantly reduced by the new magnet array. The effect on the mass and air gap is investigated compared with a conventional magnet array with rectangular permanent magnets. In conclusion, the new magnet array design has the scalability to be extended to various sizes of motor and is especially suitable for small air gap applications.


2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Longhan Xie ◽  
Ruxu Du

This paper investigates a frequency-tunable nonlinear electromagnetic energy harvester. The electromagnetic harvester mainly consists of permanent magnets supported on the base to provide a magnetic field, and electrical coils suspended by four even-distributed elastic strings to be an oscillating object. When the base provides external excitation, the electrical coils oscillate in the magnetic field to produce electricity. The stretch length of the elastic strings can be tuned to change their stretch ratio by tuning adjustable screws, which can result in a shift of natural frequency of the harvester system. The transverse force of the elastic strings has nonlinear behavior, which broadens the system's frequency response to improve the performance of the energy harvester. Both simulation and experiment show that the above-discussed electromagnetic energy harvester has nonlinear behavior and frequency-tunable ability, which can be used to improve the effectiveness of energy harvesting.


2014 ◽  
Vol 51 (1) ◽  
pp. 21-31 ◽  
Author(s):  
A. Serebryakov ◽  
N. Levin ◽  
A. Sokolov ◽  
E. Kamolins

Abstract Application of wind generators opens wide possibilities for raising the efficiency of low- and medium-power wind generators (WGs). The mass of generators in the proposed version is smaller, their reliability higher, while maintenance costs are lower. At the same time, the use of high-energy permanent magnets in generators of enhanced power comes up against some obstacles, which can be overcome through proper orientation of magnetization at creation of a magnetic field in the airgap of electrical machine. In this regard, it might be preferable to use magnets with indirect action on the airgap instead of those with direct action. A convincing example of the former variant is a generator with tangentially oriented magnetization of permanent magnets. In the work, an attempt is done to prove the advantages of such installation in modern low- and medium-power WGs


Author(s):  
Е.И. Виневский ◽  
А.В. Чернов

Исследовано влияние параметров градиентного воздействия постоянного магнитного поля (ПМП) на интенсификацию процесса томления табачных листьев. Выдвинута рабочая гипотеза о том, что для стимулирования процесса томления листьев табака необходимо градиентное воздействие на них ПМП, возникающее в результате перемещения листьев относительно системы постоянных магнитов. Введено понятие приведенного коэффициента убыли влаги, равное отношению влажности обработанных листьев к влажности контрольных образцов – необработанных листьев. Установлено, что при использовании точечного градиентного воздействия ПМП на среднюю жилку табачных листьев частотой 0,3 Гц и продолжительности обработки в течение 115–125 с при высоте расположения магнитов 25 мм процесс томления листьев ускоряется на 28,8% в сравнении с контролем. При линейном градиентном воздействии ПМП на табачный лист с частотой 0,3 Гц процесс томления ускоряется на 4,7–15,5% в зависимости от продолжительности обработки (10–40 с). При увеличении продолжительности обработки до 80 с процесс томления листьев табака замедлился. Установлено максимальное ускорение процесса томления листьев табака: при точечном градиентном воздействии ПМП на среднюю жилку табачного листа частотой 0,3 Гц и продолжительности обработки в течение 115–125 с; при линейном градиентном воздействии ПМП на табачный лист частотой 0,3 Гц и продолжительности обработки в течение 55–65 с. The influence of the parameters of the gradient effect of a constant magnetic field (CMF) on the intensification of the process of languishing tobacco leaves is studied. A working hypothesis is put forward that to stimulate the process of tobacco languor, it is necessary to have a gradient effect on them of CMF, which occurs as a result of the movement of leaves relative to the system of permanent magnets. The concept of the reduced coefficient of moisture loss is introduced, which is equal to the ratio of the humidity of treated leaves to the humidity of control samples-untreated leaves. It was found that when using a point gradient effect of CMF on the middle vein of tobacco leaves with a frequency of 0,3 Hz and a duration of processing for 115–125 s at the height of the magnets of 25 mm, the process of leaf languor is accelerated by 28,8% in comparison with the control. When the linear gradient effect of CMF on the tobacco leaf with a frequency of 0,3 Hz, the languor process is accelerated by 4,7–15,5%, depending on the duration of treatment (10–40 s). In the future, with an increase in the processing time to 80 s, the process of languishing tobacco leaves slowed down. The maximum acceleration of the process of languishing tobacco leaves is established: for spot gradient effect of CMF on the mid-veins of tobacco leaf frequency of 0,3 Hz and duration of treatment for 115–125 s; a linear gradient in the impact of CMF on the tobacco sheet with a treatment frequency of 0,3 Hz and duration of treatment for 55–65 s.


Sign in / Sign up

Export Citation Format

Share Document