• 전기학회논문지
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• 제58권4호
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• pp.735-741
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• 2009

This paper presents an algorithm for the permanent magnet shape optimization of a large scale BLDC(Brushless DC) motor to minimize the cogging torque. A response surface method (RSM) using multiquadric radial basis function is employed to interpolate the objective function in design parameter space. In order to get a reasonable response surface with relatively small number of sampling data points, additional sampling points are added on the basis of design sensitivity analysis computed by using FEM. The algorithm has 2 stages: the first stage is to determine the PM arc angle, and the 2nd stage is to optimize the magnet pole shape. The developed algorithm is applied to a 5MW BLDC motor to get a minimum cogging torque. After 3 iterations with 4 design parameters, the cogging torque is reduced to 13.2% of the initial one.

• 조명전기설비학회논문지
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• 제24권8호
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• pp.27-31
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• 2010

EPS(Elctrical Power Steering)에서 전동기의 토크 리플은 조향장치의 진동 문제를 야기한다. 따라서 EPS에서 전동기의 토크 리플 저감은 중요한 문제이며, 본 논문에서는 EPS에서 사용하는 표면부착형 영구자석 동기전동기의 토크 리플 저감에 대해 논하였다. 유한요소법을 이용하여 영구자석과 고정자 슈의 형상 변화를 통해 역기전력을 분석하였으며 이를 바탕으로 토크 리플 저감 방안을 제시하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.123-125
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• 2005

The purpose of this paper is to optimize rotor shape of interior permanent magnet (IPM) motor for high torque. V-shaped permanent magnet arrangement is applied to obtain more torque than prototype IPM. The performance, based on finite element method, is evaluated as torque per rotor volume (TRV). In this paper, response surface methodology (RSM) is used to search optimal shape of the rotor. The usefulness of RSM in optimal design of IPM motor is verified by comparing TRV between prototype and optimized V-type.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권4호
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• pp.429-435
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• 2013

This paper proposes a sensorless speed control based on a novel extension of the torque producing flux (active flux) observer for the surface mounted permanent magnet synchronous machines (SPMSM) without additional high frequency signal injection. From the estimated torque producing flux, the rotor position and speed can be calculated at low speed due to their independency. Therefore, no rotor position sensor is required. Two approaches of the torque producing flux observer are presented and compared. The results show the stability and robustness of the expansion of the torque producing flux observer at low speed for the SPMSM.

• Journal of Magnetics
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• 제19권1호
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• pp.84-89
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• 2014

This paper presents an analytical prediction and experimental verification of the electromagnetic performance of a parallel magnetized surface-mounted permanent magnet (SPM) motor having a fractional number of slots per pole combination. On the basis of a two-dimensional (2-D) polar coordinate system and a magnetic vector potential, analytical solutions for flux density produced by the permanent magnets (PMs) and stator windings are derived. Then, analytical solutions for back-electromotive force (emf) and electromagnetic torque are derived from these field solutions. The analytical results are thoroughly validated with 2-D nonlinear finite element (FE) analysis results. Finally, the experimental back-emf and electromagnetic torque measurements are presented to test the validity of the analysis.

• 전기학회논문지
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• 제66권5호
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• pp.765-771
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• 2017

This paper presents concurrent design methods of surface permanent magnet synchronous machines for saliency-tracking self-sensing position estimation. Magnetic saliency for the self-sensing is created by stator pole saturation due to the rotor zigzag leakage flux. The power conversion properties such as saliency ratio, torque ripple, and efficiency vary according to motor design. The property change due to design modification is analysed by using finite element analysis, and with the appropriate design modification, proper saliency is created while preserving their power conversion capabilities.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.202-205
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• 2008

This paper presents an optimization of permanent magnet (PM) in a brushless dc (BLDC) motor using the response surface methodology (RSM). Size and angle of the PM are optimized to minimize the cogging torque, while reducing the magnitude of harmonic at a dominant frequency and maintaining the operating torque. A fitted RS model is constructed by verifying the high reliability of the total variation and the variation of estimated error. The optimized design is validated by carrying out the reanalysis and comparing to the initial model using the nonlinear transient finite element analysis.

• Journal of Power Electronics
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• 제12권2호
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• pp.294-304
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• 2012

This paper proposes a fuzzy speed tracking controller and a fuzzy rotor angular acceleration observer for a surface-mounted permanent magnet synchronous motor (SPMSM) based on the Takagi-Sugeno (T-S) fuzzy model. The proposed observer-based controller is robust to load torque variations since it utilizes rotor angular acceleration information instead of the load torque value. Linear matrix inequality (LMI) sufficient conditions are given to compute the gain matrices of the speed tracking controller and the observer. In addition, it is mathematically verified that the proposed observer-based control system is asymptotically stable. Simulation and experimental results are presented to confirm that the proposed control algorithm assures a better transient behavior and less sensitivity under model parameter variations than the conventional PI control method.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 춘계학술대회 논문집
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• pp.321-326
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• 2013

This paper investigates the magnetic excitation force of a surface-mounted permanent magnet (SPM) motor according to the change of pole/slot combination. The characteristics of magnetic flux and radial magnetic force (RMF) due to pole/slot combination were analyzed by using magnetic circuit analysis. Also, the RMF of motors with the variable pole/slot combination was numerically simulated by using the finite element analysis to verify the result of the magnetic circuit analysis. This research shows that RMF ripple is reduced when the number of pole is smaller than the number of slot.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권2호
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• pp.127-133
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• 2013

In this paper, the authors designed a surface permanent magnet (SPM)-type vernier motor whose maximum output is more than 5.2 kW, whose power factor at 4 kW is more than 90%, and whose efficiency at 4 kW is 85% under the conditions that the operating voltage, frequency, and synchronous speed are 400 V, 50 Hz, and 100 min-1, respectively.