Novel Magnetic-field-shifting Techniques in Asymmetric Rotor Pole Interior PM Machines with Enhanced Torque Density

The torque ripple is affected by both the stator and the rotor magnetic field harmonics. In synchronous reluctance motors (SynRM), there are only rotor permeance harmonics existing on the rotor side for the absence of the rotor windings. Since the asymmetric rotor flux barriers are widely applied in the SynRM rotor, it is difficult to calculate the rotor permeance accurately by the analytical method. In this article, the effects of the rotor permeance harmonics on the air-gap magnetic field are studied by a virtual permanent magnet harmonic machine (VPMHM), which is a finite-element (FE) based magnetostatic analysis model. The air-gap flux density harmonics produced by the SynRM rotor are extracted from the VPMHM model and used as the intermediate variables for the torque ripple optimization. The proposed method does not need to solve the transient process of motor motion. Hence, the time of the optimization process can be significantly shortened. Finally, a full electric cycle is simulated by dynamic FE simulation, and the torque ripple is proved to be effectively reduced.

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High-Torque-Density IPMSM Rotor Pole Geometry Adjustment for Smooth Torque

IEEE Access ◽

10.1109/access.2019.2912346 ◽

2019 ◽

Vol 7 ◽

pp. 52650-52658 ◽

Cited By ~ 3

Author(s):

Ilya Petrov ◽

Pia Lindh ◽

Markku Niemela ◽

Eero Scherman ◽

Juha Pyrhonen

Keyword(s):

Torque Density ◽

Rotor Pole ◽

High Torque

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A Novel Bipolar Magnetic Field Crosslinking Transverse Flux Permanent Magnet Machine with High Torque Density

2019 22nd International Conference on Electrical Machines and Systems (ICEMS) ◽

10.1109/icems.2019.8921889 ◽

2019 ◽

Author(s):

Jianhui Hu ◽

Zihan Zhang ◽

Guohui Duan ◽

Cheng Liu

Keyword(s):

Magnetic Field ◽

Permanent Magnet ◽

Permanent Magnet Machine ◽

Torque Density ◽

High Torque ◽

Transverse Flux

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The Torque Characteristics of the Cycloid Permanent Magnetic Gear Based on Halbach

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.271-272.1244 ◽

2012 ◽

Vol 271-272 ◽

pp. 1244-1248

Author(s):

Wei Na Hao ◽

Xue Song Zhu ◽

Jun Zhou

Keyword(s):

Magnetic Field ◽

Finite Element Method ◽

Permanent Magnets ◽

Magnetic Torque ◽

Torque Density ◽

Halbach Array ◽

Magnetic Filed ◽

Air Gap Magnetic Field ◽

Very High ◽

Torque Angle

This paper presents a new cycloid permanent magnet gear(PM gear) based on Halbach array, which has the advantages such as extreme torque density and a very high gearing ratio. And the Halbach array can produce one-sided filed that will increase the magnetic filed intensity. The air-gap magnetic field of cycloid PM gear based on Halbach is got by adopting finite element method. At the same time, to research the torque characteristics, the factors which affect the magnetic torque of cycloid PM gear are studied respectively through the FEM, such as torque angle，offset，thickness of permanent magnets and yoke irons.

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Design of an asymmetric rotor pole for wound field synchronous machines

China Electrotechnical Society Transactions on Electrical Machines and Systems ◽

10.30941/cestems.2021.00037 ◽

2021 ◽

Vol 5 (4) ◽

pp. 321-327

Author(s):

Wenping Chai ◽

Byung-il Kwon

Keyword(s):

Synchronous Machines ◽

Rotor Pole ◽

Asymmetric Rotor

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The Zeeman Effect in Triplet States of Rotating Asymmetric Molecules

Canadian Journal of Physics ◽

10.1139/p75-237 ◽

1975 ◽

Vol 53 (19) ◽

pp. 1853-1860 ◽

Cited By ~ 15

Author(s):

J. C. D. Brand ◽

C. di Lauro ◽

D. S. Liu

Keyword(s):

Magnetic Field ◽

Field Theory ◽

Energy Levels ◽

Zeeman Effect ◽

Homogeneous Magnetic Field ◽

Triplet States ◽

Matrix Elements ◽

The Matrix ◽

Asymmetric Rotor ◽

Magnetic Tuning

Intermediate field theory is used to obtain the matrix elements which determine the action of a homogeneous magnetic field on the energy levels of triplet states of asymmetric rotor molecules. Applications of these formulas are discussed (i) in relation to the Zeeman effect on the rotational fine structure of triplet–singlet transitions, where conditions are identified under which individual lines remain unbroadened by the field, and (ii) in connection with the magnetic tuning of singlet–triplet resonance.

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Design Considerations of Switched Flux Memory Machine with Partitioned Stators

Energies ◽

10.3390/en12203868 ◽

2019 ◽

Vol 12 (20) ◽

pp. 3868

Author(s):

Jiaxing Lei ◽

Chaofan Wei ◽

Hui Yang ◽

Hao Zheng ◽

Wenjia Wang ◽

...

Keyword(s):

Finite Element ◽

Permanent Magnets ◽

Design Parameters ◽

Hybrid Magnet ◽

General Design ◽

Torque Density ◽

Design Considerations ◽

Rotor Pole ◽

Working Principle ◽

High Torque

This paper presents general design considerations of a partitioned stator switched flux hybrid magnet memory machine (PS-SF-HMMM). The armature windings and permanent magnets (PMs) are placed on two separate stators, respectively, in the PS-SF-HMMM, and thus both high torque density and wide flux regulation capability can be obtained. The topology and working principle of the machine are introduced briefly first, and then different magnet arrangements and stator/rotor pole combinations are investigated. In addition, various design parameters are optimized based on finite element (FE) methods. Finally, a prototype is fabricated to experimentally validate the FE results.

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Characteristic Performance Analysis of Traction Motor on EMU with Broken Bars Using FEM

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1061-1062.841 ◽

2014 ◽

Vol 1061-1062 ◽

pp. 841-848

Author(s):

Yong Xin Li ◽

Ya Fei Wang ◽

Xing Lai Ge ◽

Yang Lu

Keyword(s):

Magnetic Field ◽

Calculation Model ◽

Field Variation ◽

Traction Motor ◽

Squirrel Cage ◽

Squirrel Cage Induction Motor ◽

Current Variation ◽

Asymmetric Rotor ◽

Diagnosis Method ◽

Cage Induction Motor

The calculation model of motor operating on asymmetric rotor was defined taking a traction squirrel-cage induction motor in Electric Multiple Units (EMU) as sample. Based on the basic principle of numerical analysis, magnetic field in the motor and current in the bar were calculated for both normal motor and broken-bar motor by using the Jmag software, and both the magnetic field variation and current variation in the bar were summed up. According to the EMU’s special control methods, the motor with two broken bars was simulated at different work point, and the characteristic component variation was presented. The works in this paper lay the foundation of diagnosis method for broken rotor bar fault, especially for traction motor in EMU.

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Radial Force Analysis of Radial Laminated Magnetic-Barrier Rotor Brushless Doubly-Fed Machine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.171-172.454 ◽

2010 ◽

Vol 171-172 ◽

pp. 454-457 ◽

Cited By ~ 1

Author(s):

Ming Zhu Shangguan ◽

Hui Juan Liu ◽

Xin Xiao Song ◽

Hong Lin Lv

Keyword(s):

Magnetic Field ◽

Radial Force ◽

Optimized Design ◽

Force Analysis ◽

Magnetic Barrier ◽

Stator Windings ◽

Rotor Pole ◽

Radial Forces ◽

Doubly Fed ◽

Doubly Fed Machine

In this paper, the respective harmonic magnetic field generated by the two sets of stator windings of radial laminated magnetic-barrier rotor brushless doubly-fed machine has been analyzed with the winding function method, the calculations of the radial forces on stator’s inner edge which are resulted from the fundamental and harmonic magnetic field that generated by the two sets of stator windings have been made, and the radial forces of three kinds of such machines with different rotor pole numbers have been compared, all the above can provide theoretical guidance for optimized design of radial laminated magnetic-barrier rotor brushless doubly-fed machine.

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Partitioned Stator Switched Flux Machine: Novel Winding Configurations

Entropy ◽

10.3390/e22090920 ◽

2020 ◽

Vol 22 (9) ◽

pp. 920

Author(s):

Muhammad Irfan ◽

Naveed Ur Rehman ◽

Faisal Khan ◽

Fazal Muhammad ◽

Abdullah S. Alwadie ◽

...

Keyword(s):

Analytical Modeling ◽

Limiting Factors ◽

Power Splitting ◽

Flux Linkage ◽

Element Analysis ◽

Torque Density ◽

Rotor Pole ◽

Electromagnetic Characteristics ◽

Current Densities ◽

Torque Ripples

Torque density is one of the major limiting factors in machine design. In this paper, we propose the hybrid excited partitioned stator switched flux machine3 (HE-PSSFM3). In HE-PSSFM3, armature winding is positioned on the outer stator whereas the permanent magnet (PM) and field winding are placed at the inner stator, while the rotor is free from excitation sources and armature winding. Moreover, concentrated field winding is replaced by toroidal winding. The power splitting ratio between two stators/rotor pole combinations is analytically optimized and are validated through genetic algorithm (GA) in order to enhance average torque and flux regulation capability. The electromagnetic characteristics of the improved and initial design are evaluated and compared with existing designs, i.e., HE-PSSFM1 and HE-PSSFM2. The proposed HE-PSSFM3 has achieved high average torque, i.e., 2.0015 Nm, at same armature and field current densities of 5 A/mm2. The results show that the average torques of the proposed design are 35% and 15% greater than HE-PSSFM1 and HE-PSSFM2, respectively. Furthermore, the analysis of various parameters such as flux linkage, flux regulation, electromagnetic performances, cogging torque, back EMF, electromagnetic torque, and torque ripples are investigated using two dimensional (2D) finite element analysis (FEA). Moreover, the simulation results of the proposed design are validated through GA and analytical modeling.

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