• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.179.2-179.2
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• 2010

This research has been performed to provide fundamental design aspects of Permanent Magnet Synchronous Generators(PMSGs) for a kilowatt class wind turbine. When it comes to kilowatt class wind turbines, the typical type of generators are Axial Flux Permanent Magnet(AFPM) generators. However, Radial Flux Permanent Magnet(RFPM) generators have been optimally designed to study the output characteristics of a kilowatt class wind turbine in Graduate School of Wind Energy, POSTECH. An existing squirrel-cage rotor has been modified for another newly designed permanent magnet rotor to utilize the commercially existing stator rotor. Electromagnetic analysis utilizing Finite Element Methods tools(ANSYS, MAXWELL 2D) has been applied to analyze the system.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1015-1016
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• 2011

본 논문에서는 권선 방법에 따라 코일 U, V, W를 같은 층에 원주방향으로 배치한 집중권 권선 모델, 코일 U, V, W를 각각 한 층씩 원주 방향으로 배치한 분포권 권선 #1 모델, 코일에 경사각을 적용하여 코일 U, V, W를 한 층에 배치하는 분포권 #2 모델로 총 3가지 사양의 3상 코어리스 축방향 자속 발전기를 설계하였다. 3차원 유한요소 해석을 활용하여, 무부하 상태에서의 역기전력, 쇄교 자속 밀도와 외부 정류 회로를 구성한 부하 상태에서의 정류 전압, 정류 전류와 같은 전자기 특성에 대한 해석 및 특성 비교를 수행하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1019-1020
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• 2011

This paper deals with torque analysis of axial flux permanent magnet (AFPM) type eddy current brake (ECB) based on analytical field computation. On the basis of a magnetic vector potential and a two-dimensional (2-D) polar coordinate system, analytical solutions for normal and tangential flux density due to permanent magnet (PM) considering eddy current effect are obtained. And then, using derived analytical field solutions, braking torque and normal force characteristics according to rotor speed are also predicted. A three-dimensional (3-D) finite element (FE) analysis is employed to confirm the validity of analyses.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.9
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• pp.437-442
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• 2006

Cogging torque, the primary ripple component in the torque generated by permanent magnet (PM) motors, is due to the slotting on the stator or rotor. This article shows the reduction of cogging torque in a novel axial flux permanent magnet (AFPM) motor through the various design schemes. 3D finite element method is used for the exact magnetic field analysis. The effects of slot shapes and skewing of slot on the cogging torque and the average torque have been investigated in detail.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.2 s.179
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• pp.172-180
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• 2006

Although there existed many types of manual/power hybrid wheelchairs, their use was not widespread because of their inconvenience in converting drive system and in folding frames. To carry a wheelchair in the car or to convert driving methods, some hard work of disassembling or exchanging wheels was required for most of currently available hybrid wheelchairs. In this study, the standard foldable manual wheelchair was reformed to a power wheelchair by installing the newly developed Axial Flux Permanent Magnet(AFPM) type of brush less direct current(BLDC) motor on each rear hub of wheelchair. This wheelchair could be driven by manual or electric power without exchanging. wheels, thus no additional work was needed for carriage or for power conversion. The developed wheelchair was evaluated for durability, stability, maneuverability, cost, and reliability in accordance with the Korean standards. The results indicated that the developed hybrid wheelchair was good enough for commercialization comparing to other imported wheelchairs.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1005-1007
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• 2005

Small wind turbines are becoming a viable technology option to supply electricity to landowners. These systems provide energy security, product relatively no environmental harm, and in an appropriate setting can be quite cost-competitive with traditional electricity options. This paper is dealing with the methods how to overcome such inconvenience and with the analysis of characteristic and a field test with a prototype of the stand alone wind turbine was performed. The method applies to small systems, equipped with a coreless axial-flux permanent magnet(AFPM) generator in the turbine, a dc-dc converter and batteries. The analysis concentrates on the effect of the load on the power-wind speed curve of the turbine. The system is designed for direct driven, coupled with turbine and generator with a rated power of, 3kW.