The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
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Cogging Torque Reduction in AFPM Generator Design for Small Wind Turbines

소형 풍력발전기용 AFPM 발전기 코깅토크 저감 설계

  • 정대원 (호남대학교 공대 전기공학과)
  • Received : 2012.07.20
  • Accepted : 2012.11.20
  • Published : 2012.12.01
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Abstract

This paper is to present a new method of cogging torque reduction for axial flux PM machines of multiple rotor surface mounted magnets. In order to start softly and to run a power generator even the case of weak wind power, reduction of cogging torque is one of the most important issues for a small wind turbine, Cogging torque is an inherent characteristic of PM machines and is caused by the geometry shape of the machine. Several methods have been already applied for reducing the cogging torque of conventional radial flux PM machines. Even though some of these techniques can be also applied to axial flux machines, manufacturing cost is especially higher due to the unique construction of the axial flux machine stator. Consequently, a simpler and low cost method is proposed to apply on axial flux PM machines. This new method is actually applied to a generator of 1.0kW, 16-poles axial flux surface magnet disc type machine with double-rotor-single-stator for small wind turbine. Design optimization of the adjacent magnet pole-arc which results in minimum cogging torque as well as assessment of the effect on the maximum available torque using 3D Finite Element Analysis (FEA) is investigated in this design. Although the design improvement is intended for small wind turbines, it is also applicable to larger wind turbines.

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References

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