Effect of Magnetization Pattern on Partial Demagnetization of Rotary Electric Machines with Ferrite Magnets

페라이트 영구자석을 이용한 회전형 전기기기의 착자 형태에 따른 부분 감자의 영향

  • Kim, Kwan-Ho (Dept. of Electrical and Electronic Engineering, Chung Nam University) ;
  • Park, Hyung-Il (Dept. of Electrical and Electronic Engineering, Chung Nam University) ;
  • You, Dae-Joon (Dept. of Fire Safety Engineering Chungnam State University) ;
  • Jang, Seok-Myeong (SEMS High-Tech Engineering. co. Ltd.) ;
  • Choi, Jang-Young (Dept. of Electrical Engineering, Chungnam National University)
  • Received : 2015.08.28
  • Accepted : 2015.11.18
  • Published : 2015.12.01


This paper examines the effect of the magnetization pattern on the partial demagnetization of a permanent magnet (PM) machine that uses a ferrite magnet. Although the use of halbach-magnetized PM (HMPM) arrays in PM machines has been dramatically increasing because of their attractive features, the demagnetization characteristics of HMPM arrays have not yet been examined. In this study, two analyses of the demagnetization characteristics of HMPM arrays and parallel magnetized PMs (PMPMs) are performed, with the demagnetization characteristics being analyzed using a finite element method. According to our results, partial demagnetization occurred dramatically in the HMPM arrays. Thus, it is important to consider the vulnerability of HMPM arrays when designing PM machines.


Supported by : 한국연구재단


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