Energetic problems of permanent magnetic attraction systems with variable leakage permeance depending on the air gap

In this paper a formula of estimation of magnetic attraction force in the relative base – air-gap – absolute base system is presented. The attraction force of the relative base (forcer) to the ferromagnetic absolute base (stator) is a result of the attraction of permanent magnets, which are the components of the electromagnetic modules. The physical model and mathematical description of the particular electromagnetic module are presented.

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Effect of the forces of one-way magnetic attraction on the reliability of the bearing unit of the traction switched reluctance motor

Journal of Physics Conference Series ◽

10.1088/1742-6596/2131/4/042078 ◽

2021 ◽

Vol 2131 (4) ◽

pp. 042078

Author(s):

Y Y Miroshnichenko

Keyword(s):

Rotation Axis ◽

Switched Reluctance Motor ◽

Air Gap ◽

Switched Reluctance ◽

Design Elements ◽

Magnetic Attraction ◽

Axis Of Rotation ◽

First Case ◽

Reluctance Motor ◽

Axis Of Symmetry

Abstract The subject of the research is a traction switched reluctance motor with an uneven air gap. The main purpose of the work is to determine the forces of one-way magnetic attraction, evaluate and analyze these forces, develop measures to reduce the forces to an acceptable value. In the article, the forces of disbalancement and the forces of one-way magnetic attraction are considered in the relationship. The finite element method was used to determine the main parameters of the switched reluctance motor. The studies were carried out for two idealized variants of the location of the rotor rotation axis. In the first case, the axis of rotation is combined with the axis of symmetry of the stator. The second option considers the case of displacement of the axis of rotation together with the axis of symmetry of the rotor. It is determined that the resulting force of one-way magnetic attraction with an uneven air gap reaches significant values and significantly exceeds the permissible values. An algorithm for calculating the characteristics of a switched reluctance motor is proposed, which takes into account the tolerances for the manufacture of its design elements. The algorithm allows you to adjust the requirements for the bearings used, ensure the required level of reliability of the traction switched reluctance motor (SRM) and predict the level of vibration and noise.

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INCREASED RELIABILITY OF THE BEARING UNIT OF A TRACTION MOTOR OF THE SWITCHED RELUCTANCE TYPE FOR TRANSPORT SYSTEMS

Chronos Journal ◽

10.52013/2658-7556-54-4-7 ◽

2021 ◽

Vol 6 (4(54)) ◽

pp. 29-32

Author(s):

Ekaterina Evgenievna Miroshnichenko

Keyword(s):

Switched Reluctance Motor ◽

Air Gap ◽

Transport Systems ◽

Traction Motor ◽

Switched Reluctance ◽

Magnetic Attraction ◽

Bearing Unit ◽

Reluctance Motor ◽

The Subject

The subject of research is the traction switched reluctance motor for transport systems with uneven air gap. The calculation of the forces of one-way magnetic attraction during displacement of the rotor is carried out. It has been shown that these forces reach high values and exert an influence on the bearings leading to their premature wear. Measures are proposed to reduce the influence of one-way magnetic attraction forces and to increase the reliability of the bearing unit.

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A novel analytical calculation of magnetic field in the slotted air gap of spoke-type permanent-magnet machines using conformal mapping

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-201505 ◽

2020 ◽

pp. 1-15

Author(s):

Jianqi Li ◽

Yu Zhou ◽

Jianying Li

Keyword(s):

Magnetic Field ◽

Conformal Mapping ◽

Permanent Magnet ◽

Flux Density ◽

Analytical Method ◽

Electromotive Force ◽

Analytical Calculation ◽

Air Gap ◽

Permanent Magnet Machines ◽

Peak Value

This paper presented a novel analytical method for calculating magnetic field in the slotted air gap of spoke-type permanent-magnet machines using conformal mapping. Firstly, flux density without slots and complex relative air-gap permeance of slotted air gap are derived from conformal transformation separately. Secondly, they are combined in order to obtain normalized flux density taking account into the slots effect. The finite element (FE) results confirmed the validity of the analytical method for predicting magnetic field and back electromotive force (BEMF) in the slotted air gap of spoke-type permanent-magnet machines. In comparison with FE result, the analytical solution yields higher peak value of cogging torque.

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Effects of contact gap on nondestructive evaluation using magnetic measurement for ferromagnetic steel

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209411 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 969-975

Author(s):

Hiroaki Kikuchi ◽

Yuki Sato

Keyword(s):

Magnetic Flux ◽

Nondestructive Evaluation ◽

Effective Permeability ◽

Magnetic Circuit ◽

Magnetic Measurement ◽

Air Gap ◽

Motive Force ◽

Hysteresis Curve ◽

Evaluation Technique ◽

Ferromagnetic Steel

We investigated effects of contact gap on magnetic nondestructive evaluation technique using a magnetic single-yoke probe. Firstly, we evaluated hysteresis curves and impedance related to permeability of the material measured by a single-yoke probe, when an air gap length between the probe and specimens changes. The hysteresis curve gradually inclines to the axis of the magneto-motive force and magneto-motive force at which the magnetic flux is 0 decreases with increasing the gap length. The effective permeability also decreases with increasing the gap thickness. The incremental of gap thickness increases the reluctance inside the magnetic circuit composed of the yoke, specimen and gap, which results in the reduction of flux applying to specimen.

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