Air-Gap Magnetic Field Analysis of Wind Generator With PM Embedded Salient Poles by Analytical and Finite Element Combination Technique

Purpose The purpose of this paper is to present an improved conformal mapping (ICM) method that simultaneously considers the influence of relative recoil permeability of PMs, the armature reaction, the stator slotting, and the magnetic saturation on determination of the PM operating point in its different parts. Design/methodology/approach The ICM method is a time-effective method that considers the magnetic saturation by suitable increments in air-gap length under each tooth and also the width of slot openings. In this paper, the analytical and numerical conformal mappings such as the Schwarz-Christoffel (SC) mapping are used for magnetic field analysis due to the permanent magnets and the armature reaction in one slotted air gap. The field solution in the slotted air gap is obtained through the modulation of field solution in one slotless air-gap using the complex air-gap permeance. Findings The ICM method can consider the magnetic saturation in different electric loadings, and also the variation of PM operating points in its different parts. Practical implications The ICM method is applied to one surface mounted permanent magnet (SMPM) motor and is verified by comparing with the corresponding results obtained through finite element method (FEM), and frozen permeability finite element method (FP-FEM). Originality/value This paper presents an ICM method with a new technique for saturation effect modeling, which can be used to separate and calculate the on-load components of air-gap field and torque.

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Magnetic field analysis of Primary Permanent Magnet Linear Motor Based on Halbach Distribution

E3S Web of Conferences ◽

10.1051/e3sconf/202020402012 ◽

2020 ◽

Vol 204 ◽

pp. 02012

Author(s):

Xiuping Wang ◽

Yan Li ◽

Chuhan Yang ◽

Chunyu Qu

Keyword(s):

Magnetic Field ◽

Permanent Magnet ◽

Technical Problem ◽

Linear Motor ◽

Air Gap ◽

Field Analysis ◽

Transit System ◽

Finite Element Software ◽

Magnetic Field Analysis ◽

Air Gap Magnetic Field

The rail transit system driven by linear motor has outstanding advantages in climbing ability, traction performance, vibration and noise. However, with the increase of traffic travel and other situations, how to ensure that the linear motor still has a large thrust and stability in the air gap condition is the key technical problem. In order to solve this problem, three Halbach permanent magnet array structures are proposed and applied to the magnetic barrier coupled primary permanent magnet unilateral excitation linear motor (MBCPPMUELM). The finite element software is used for simulation and analysis. By comparing the harmonic distribution of air gap magnetic field of the three Halbach permanent magnet array motors, a topology structure with high magnetic field modulation effect is obtained It provides a useful reference for the further design and analysis of this kind of motor.

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Electromagnetic Performance Analysis of Claw-Pole Alternator with Changing Permeance

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.668.510 ◽

2013 ◽

Vol 668 ◽

pp. 510-513

Author(s):

Xiao Hua Bao ◽

Mou Zhi Liu

Keyword(s):

Magnetic Field ◽

High Speed ◽

Noise Analysis ◽

Calculation Model ◽

Air Gap ◽

Field Analysis ◽

Electromagnetic Properties ◽

Magnetic Field Analysis ◽

Field Distortion ◽

Air Gap Magnetic Field

A changing air gap permeance model of the alternator and its influence were discussed in this paper. When the alternator was under high-speed operation, taking it into consideration that the claws getting deformation for rotating centrifugal force and electromagnetic exciting force, the alternator’s changing air gap permeance model was established. And the alternator’s Maxwell3D calculation model was built. The field magnetic distribution under the rated speed was obtained as well, also before the claws’ deformation was obtained. The harmonics of the air-gap flux were analyzed and compared. The changing air gap permeance model was proved to be reasonable. It would lead to air-gap magnetic field distortion of the generator, which affected the generator’s electromagnetic properties. Instruction was provided for more precise of air gap magnetic field analysis or vibration noise analysis of alternator.

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Analytical Calculation Model of Air-Gap Magnetic Field for Claw Pole Machine with Outer PM Rotor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.588-589.463 ◽

2012 ◽

Vol 588-589 ◽

pp. 463-466

Author(s):

Guang Wei Liu ◽

Feng Ge Zhang ◽

Jin Xiang Gao

Keyword(s):

Magnetic Field ◽

Finite Element ◽

3D Structure ◽

Analytical Calculation ◽

Calculation Model ◽

Air Gap ◽

Field Analysis ◽

Polar Coordinates ◽

Element Analysis ◽

Air Gap Magnetic Field

In view of the time consuming and sensitive to finite element meshes, the finite element method is not suitable for claw pole machine with outer permanent magnet rotors with complicated and asymmetric 3D structure. A new analytical calculation model based on air-gap magnetic field analysis in polar coordinates is proposed. According to boundary conditions, the radial and tangential flux density is obtained by using the Fourier’s series, and then the cogging torque and no load EMF is calculated. In order to verify the accuracy of the analytical method, the finite element analysis is finished. Moreover, one prototype is manufactured and measured also. The analytical results well agree with those obtained by the FEM and experiments, confirmed the feasibility of this method.

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