Electromagnetic torque prediction and harmonic reduction of interior permanent magnet synchronous motor for electric vehicles using an analytical method

Interior permanent magnet synchronous motors (IPMSMs) have been widely used as drive machines in electric vehicles (EVs) due to their high torque density. However, the torque ripple of IPMSMs will result in severe noise and vibration. This paper proposes a new analytical method for electromagnetic torque prediction and harmonic reduction of IPMSM. On the basis of dq theory, an analytical model of electromagnetic torque is firstly established by taking the permanent magnet flux harmonics and the cross-coupling effect into consideration. And the specific sources and orders of torque harmonics are also determined. Then, the torque-angle characteristics are further studied. In particular, the permanent magnet (PM) torque and the reluctance torque are separated and quantitatively analyzed via the proposed analytical model. Finally, a theoretical method of reducing the specific order torque harmonic by PM shifting is derived and proposed from the perspective of avoiding resonance. The accuracy and effectiveness of the proposed analytical method are verified by finite-element analysis. The results show that the proposed analytical model is accurate enough to predict the electromagnetic torque performance of IPMSM. Moreover, the electromagnetic torque harmonics with specific orders can be effectively reduced by shifting the PM to an appropriate angle.

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Performances analysis of interior permanent magnet motors having different rotor iron pole shapes

International Journal of Power Electronics and Drive Systems (IJPEDS) ◽

10.11591/ijpeds.v12.i4.pp1999-2005 ◽

2021 ◽

Vol 12 (4) ◽

pp. 1999

Author(s):

Ahlam Luaibi Shuraiji ◽

Buraq Abdulhadi Awad

Keyword(s):

Permanent Magnet ◽

Torque Ripple ◽

High Energy ◽

Electromagnetic Torque ◽

Permanent Magnet Motors ◽

Element Analysis ◽

Magnet Material ◽

Interior Permanent Magnet ◽

Rotor Pole ◽

Permanent Magnet Material

<p><span lang="EN-US">Interior permanent magnet motors (IPMMs) have been increasing in popularity, since the emergence of permanent magnet material with high energy products, i.e. rare earth permanent magnet material. This paper analyses the performances of IPMMs having different rotor iron pole shapes including eccentric, sinusoidal and sinusoidal with 3th order harmonic injected rotor pole arc shapes IPMMs. Cogging torque, static torque, torque ripple, torque-speed and power-speed curves of the mentioned motors have been compared. It must be noted that the mentioned motors have been designed with the same stator, PM shape and the same dimensions, in order to highlight the effect of the rotor pole arc shape on the performance of the such motors. Two-dimensional (2D) finite element analysis (FEA) has been utilized to design and analyze the mentioned machines. It has been found that rotor iron pole shape of the IPM has notably influence on the machine performance, practically on output electromagnetic torque and its ripple. The highest value of average electromagnetic torque as well as torque capability in the constant torque reign is delivered by 3th order harmonic injected rotor pole arc shapes machine, while the lowest torque ripple is obtained by the sinusoidal rotor pole arc machine.</span></p>

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Torque imporvement of IPM motors with skewing magnetic designs

Journal of Military Science and Technology ◽

10.54939/1859-1043.j.mst.76.2021.3-10 ◽

2021 ◽

pp. 3-10

Author(s):

Dinh Hai Linh

Keyword(s):

Permanent Magnet ◽

High Speed ◽

Torque Ripple ◽

Maintenance Cost ◽

Permanent Magnet Motor ◽

Element Analysis ◽

Speed Range ◽

Interior Permanent Magnet ◽

Interior Permanent Magnet Motor ◽

Wide Speed Range

In this paper, a type interior permanent magnet synchronous motor designs is proposed for sport scooter application to improve constant torque wide speed performance. Interior Permanent Magnet machines are widely used in automotive applications for their wide-speed range operation and low maintenance cost. An existing permanent magnet motor (commercial QS Motor) is 3 kW-3000 rpm. In order to improve torque and power in wide speed range, a IPM electric motor 5.5 kW -5000 rpm can run up to 100 km/h: An Step-Skewing Interior Permanent Magnet motor alternatives is designed and optimized in detail with optimal magnetic segment V shape. The electromagnetic charateristics of Interior Permanent Magnet motors with V shape are compared with the reference Surface Permanent Magnet motor for the same geometry parameter requirements. Detailed loss and efficiency result is also analyzed at rate and maximum speeds. A prototype motor is manufactured, and initial experimental tests are performed. Detailed comparison between Finite Element Analysis and test data are also presented. It is shown that it is possible to have an optimized Interior Permanent Magnet motor for such high-speed traction application. This paper will figure out optimal angle of magnetic V shape for maximum torque and minimum torque ripple.

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Sensitivity-Based Optimization of Interior Permanent Magnet Synchronous Motor for Torque Characteristic Enhancement

Energies ◽

10.3390/en14082240 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2240

Author(s):

Sajjad Ahmadi ◽

Thierry Lubin ◽

Abolfazl Vahedi ◽

Nasser Taghavi

Keyword(s):

Sensitivity Analysis ◽

Finite Element ◽

Permanent Magnet ◽

Permanent Magnet Synchronous Motor ◽

Computational Cost ◽

Torque Ripple ◽

Synchronous Motor ◽

Element Analysis ◽

Multi Objective ◽

Interior Permanent Magnet

This paper presents a multi-objective optimal rotor design for an interior permanent magnet synchronous motor (IPMSM) based on finite element analysis. Due to the importance of torque characteristic in electromagnetic design of IPMSMs, the main efforts of this study are focused on finding a proper trade-off for its torque profile challenges. In this regard, in order to attain high average torque and low torque ripple, the influence of several key factors, such as the permanent magnet (PM) arrangements, PM positions and PM sizes, are examined. Subsequently, according to the outcomes of the performed sensitivity analysis, the appropriate variation interval of the parameters as well as their initial values is determined. Employing such a deterministic optimization algorithm, which does not need large sample points, minimizes the finite element computational cost and leads to accelerate the convergence process. The two-dimensional finite element model (FEM) of an IPMSM is used to perform a sensitivity analysis and establish a multi-objective FEM-based optimization.

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Design and Analysis of Rotor Shapes for IPM Motors in EV Power Traction Platforms

Energies ◽

10.3390/en11102601 ◽

2018 ◽

Vol 11 (10) ◽

pp. 2601 ◽

Cited By ~ 8

Author(s):

Myeong-Hwan Hwang ◽

Jong-Ho Han ◽

Dong-Hyun Kim ◽

Hyun-Rok Cha

Keyword(s):

Permanent Magnet ◽

Electric Vehicles ◽

High Power ◽

High Efficiency ◽

Torque Ripple ◽

Hybrid Vehicles ◽

Recent Increase ◽

Interior Permanent Magnet ◽

Rotor Shape ◽

Two Hybrid

The recent increase in the use of permanent magnet rotor motors underlines the importance of designing a rotor with an interior permanent magnet (IPM) structure, high power, and high efficiency. This study analyzed the rotor shapes of IPM motors for electric vehicles. Five types of motor rotors for automobiles were analyzed, including two hybrid vehicles. In order to minimize the number of variables in the analysis, the size of the motor stators was fixed and only the rotor shapes were modified to compare torque, torque ripple, efficiency and back-electromotive voltage. When the motor properties were compared as a function of rotor shape, the rotor shape with the smallest magnet volume exhibited excellent results for torque, efficiency and torque ripple.

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Multi-Objective Optimization of Permanent Magnet Synchronous Motor for Electric Vehicle Considering Demagnetization

Applied Sciences ◽

10.3390/app11052159 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2159

Author(s):

Yong-min You ◽

Keun-young Yoon

Keyword(s):

Permanent Magnet ◽

High Temperatures ◽

Electric Vehicles ◽

Permanent Magnets ◽

High Reliability ◽

Torque Ripple ◽

Experimental Point ◽

Multi Objective Optimization ◽

Element Analysis ◽

Multi Objective

The irreversible demagnetization of permanent magnets causes the deterioration of the performance in permanent magnet synchronous motors (PMSMs), which are used for electric vehicles. NdFeB, which is the permanent magnet most commonly used in PMSMs for electric vehicles, is easily demagnetized at high temperatures. Because traction motors for electric vehicles reach high temperatures, and a high current can be instantaneously applied, permanent magnets of PMSM can be easily demagnetized. Therefore, it is important to study the demagnetization phenomenon of PMSMs for electric vehicles. However, since the demagnetization analysis procedure is complicated, previous studies have not been able to perform optimization considering demagnetization characteristics. In this study, we optimized the shape of a PMSM for electric vehicles by considering the demagnetization characteristics of permanent magnets using an automated design of experiments procedure. Using this procedure, a finite element analysis for each experimental point determined by a sampling method can be performed quickly and easily. The multi-objective function minimizes the demagnetization rate and maximizes the average torque, and the constraints are the efficiency and torque ripple. Various metamodels were generated for each of the multi-objective functions and constraints, and the metamodels with the best prediction performance were selected. By applying a multi-objective genetic algorithm, 1902 various optimal solutions were obtained. When the weight rate of the demagnetization rate to the torque was set to 0.1:0.9, the demagnetization rate and average torque were improved by 4.45% and 2.7%, respectively, compared to those of the initial model. The proposed multi-objective optimization method can guide the design of PMSMs for electric vehicles with high reliability and strong demagnetization characteristics.

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VARIATION OF ELECTRIC PROPERTIES BETWEEN SURFACE PERMANENT MAGNET AND INTERIOR PERMANENT MAGNET MOTOR

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512003029 ◽

2012 ◽

Vol 06 ◽

pp. 109-114

Author(s):

BYUNG-CHUL WOO ◽

DO-KWAN HONG ◽

JI-YOUNG LEE

Keyword(s):

Permanent Magnet ◽

Complex Geometry ◽

Torque Ripple ◽

Direct Drive ◽

Element Analysis ◽

Torque Density ◽

Interior Permanent Magnet ◽

3D Fea ◽

High Torque ◽

Transverse Flux

The most distinctive advantage of transverse flux motor(TFM) is high torque density which has prompted many researches into studying various design variants. TFM is well suited for low speed direct drive applications due to its high torque density. This paper deals with simulation based comparisons between a surface permanent magnet transverse flux motor(SPM-TFM) and an interior permanent magnet transverse flux motor(IPM-TFM). A commercial finite element analysis(FEA) software Maxwell 3D is used for electromagnetic field computation to fully analyze complex geometry of the TFMs. General characteristics, such as cogging torque, rated torque and torque ripple characteristics of the two TFMs are analyzed and compared by extensive 3D FEA.

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

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209410 ◽

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.

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