• International Journal of Advanced Culture Technology
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• v.11 no.1
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• pp.337-342
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• 2023

Since the electric vehicle uses an electric motor, problems have arisen as the driver hears the inherent noise of the motor or external noise, which was not a problem in the past, due to the overall lower noise environment than when using an internal combustion engine. Therefore, the purpose of this paper is to reduce the noise and vibration of electric motors for electric vehicles, and recently, to increase the speed of high-power, high-efficiency electric motors in a small size, and to develop low-noise motors, IPM motors are applied to produce 35KW electric motors for electric vehicles. A motor for low noise was designed and implemented. N-T Curve and efficiency map were confirmed as the final result of developing a 35KW low-noise motor for electric vehicles by applying the IPM motor applied in this paper. Based on 3500 rpm, Max Torque [Nm]: 121.15, Max Power [KW]: 44.04, and Max Efficiency [%]: 97.65, showing high efficiency.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.1
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• pp.45-52
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• 2023

The power generation method using expensive diesel has operation problems such as high cost diesel generator and a lack of reserved power due to increase of power demand in some islands, requiring expansion of power generation facilities. To solve this problems, it is necessary to improve the efficiency of power generation facilities through an ORC(Organic Rankin Cycle) system application that uses waste heat as a heat source. Therefore, localized application technology of price competitive and highly reliable ORC power generation system is needed, and optimization technology of generators is having great effect, so this study performed two generator designs to get a high-efficiency generator with an optimized 30kW output. The comparison of simulation data for two designed models showed that a generator with SPM factor of 46.2% had an efficiency of 92.1% and a power ouput of about 23.2kW based on 12,000rpm, a generator with SPM factor of 44.46%, had a power output of 27.9kW and efficiency of 93.6% based on above rpm. For the verification of improved design model with SPM factor of 44.46%, the prototype test system with 110kW motor dynamometer was installed and got to the efficiency of 92.08% with conditions of the rated capacity 25kW at 12,000rpm, the test results of prototype generator showed the validity of generator design.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.659-660
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• 2015

본 논문에서는 자동차 전장용 3상 BLDC 전동기의 출력특성 향상을 위해 비대칭 공극 구조 설계 방법에 대해 연구하였다. SPM 타입 BLDC 전동기의 공극을 비대칭적으로 설계함으로써 자기적 토크 외에도 릴럭턴스 토크가 발생하게 된다. 따라서 전류 당 토크의 증가로 인해 출력특성을 향상시켰으며 2D 유한요소해석을 통해 본 논문의 타당성을 검증하였다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.732-733
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• 2015

본 논문에서는 외전형 영구자석 동기전동기(Outer rotor Permanent Magnet Synchronous Motor)의 회전자 형상에 따른 토크특성을 비교하였다. 표면부착형 영구자석(SPM) 형태의 FAN용 PMSM을 설계하고 이 모델을 기준으로 동일한 외경사이즈를 갖지만 더 높은 토크 밀도를 갖는 4가지 매입형 영구자석(IPM) 형태의 PMSM을 제시한다. Finite Element Analysis(FEM)을 통하여 각 모델의 특성을 해석하고 자석 사용량과 토크를 비교 및 분석하였다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.938-939
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• 2015

3상 BLDC 전동기의 경우, PMSM보다 간단하며 제어가 상대적으로 용이하다는 장점을 갖는다. 본 논문에서는 기존의 IPM의 최대 토크 운전 방식에서 착안하여 기존의 SPM타입의 전동기 운전방식과는 달리 최대 토크 지점에 인가되는 유효전압을 상승시켜 토크의 활용률 및 효율 특성을 향상시키는 운전방식을 제안한다. 유한요소해석 및 시뮬레이션을 통해 제안된 운전방식의 타당성을 검증하였다.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2761-2763
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• 1999

In this paper, we analyzed the characteristics of the detected EMF signals used to detect the rotor position in the IPM(Interior Permanent Magnet) BLDC motor and SPM (Surface Permanent Magnet) BLDC motor. The position sensing signal, in the IPM BLDC motors, advances the real rotor position due to the variation of the rotor inductances. This fact was verified by the simulation and experiment.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.281-285
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• 1990

Our N.C. sewing machine is a device that acts sewing automatically in reference to N.C. data made by data input device. Our N.C. sewing mechine is composed of induction motor that has electric clutch and brake, step motor that drives x-y table. Sewing area of our machine is 170 mm * 100 mm, maximum sewing speed is about 2000 spm, maximum stitch length 6.2 mm. In actual sewing, synchronization between motion of needle up-down and motion of x-y table is a critical factor. In this paper, technology about synchronization will be profoundly discussed.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.824-827
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• 2003

Recently, Development of Rare Earth Permanent magnet with the high remanence, high coercivity allow the design of brushless motors with very high efficiency over a wide speed range. Cogging torque is produced in a permanent magnet by magnetic attraction between the rotor mounted permanent magnet and the stator teeth. It is an undesired effect that contributes to the machines output ripple, vibration, and noise. This cogging torque can be reduced by variation of magnet arc length, airgap length, magnet thickness, shifting the magnetic pole and varying the radial shoe depth and etc. In this paper, Some airgap length and magnet arc that reduce cogging torque are found by FEM(Finite element method). The SPM type of high-capacity BLDC motor is optimized as a sample model.

• Investigative Magnetic Resonance Imaging
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• v.10 no.1
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• pp.26-31
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• 2006

Purpose : To evaluate the effect of global scaling analysis on brain activation for sensory and motor functional MR imaging study. Materials and methods : Four normal subjects without abnormal neurological history were included. Arm extension-flexion movement was used for motor function and 1KHz pure tone stimulation was used for auditory function. Functional magnetic resonance imaging was performed at 3T MRI (GE, Milwaukee, USA) using BOLD-EPI technique and SPM2 was employed for data analysis. On data analysis, the brain activation images were obtained with and without global scaling by fixing other parameters such as motion correction and realignment. Results : The difference in brain activation between no scaling and global scaling was not large in case of right upper extremity movement (p<0.000001). For auditory test, brain activation with global scaling showed larger activation than that of without global scaling (p<0.05). Conclusion : A caution must be taken into account when analyzing functional imaging data with global scaling especially for functional study of small local BOLD signal change.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.3
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• pp.165-173
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• 2013

Core loss has a major effect on heat generation in synchronous motors with surface-mounted permanent magnets (SPMs). It is essential to perform heat transfer analysis considering core loss in SPM because core loss is seriously affected by torque and speed of motors. In the present study, mechanical loss, core loss and coil loss are evaluated by measuring input and output energies under various driving conditions. For a better understanding heat transfer paths in synchronous motors, we developed a lumped thermal system analysis model. Subsequently, heat transfer analysis has been performed based on acquired energy loss, temperature data and thermal resistance with three types of SPM. It is shown that the torque constants decrease by Max. 10% as speed increase. At the rated torque, the core loss is Max. 10.9 times greater than the coil loss and the hysteresis loss of magnets is dominant in total loss.