Eddy-Current Loss Analysis in Rotor of Surface-Mounted Permanent Magnet Machines Using Analytical Method

해석적 방법을 이용한 표면부착형 영구자석 기기의 회전자 와전류 손실해석

  • 최장영 (충남대 전기공학과) ;
  • 최지환 (충남대 전기공학과) ;
  • 장석명 (충남대 전기공학과) ;
  • 조한욱 (충남대 전기전자통신교육과) ;
  • 이성호 (한국생산기술연구원 광주 연구센터/부품소재팀)
  • Received : 2011.12.02
  • Accepted : 2012.07.23
  • Published : 2012.08.01


This paper analyzes eddy-current loss induced in magnets of surface-mounted permanent magnet (SPM) machines by using an analytical method such as a space harmonic method. First, on the basis of a two-dimensional (2D) polar coordinate system and a magnetic vector potential, the analytical solutions for the flux density produced by armature winding current are obtained. By using derived field solutions, the analytical solutions for eddy current density distribution are also obtained. Finally, analytical solutions for eddy current loss induced in rotor magnets are derived by using equivalent electrical resistance calculated from magnet volume and analytical solutions for eddy-current density distribution. In particular, the influence of time harmonics in armature current on the eddy current loss is fully investigated and discussed. All analytical results are validated extensively by finite element analysis (FEA).


Supported by : 한국연구재단


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