A quantitative comparative analysis of a novel flux-modulated permanent-magnet motor for low-speed drive

Weinong Fu, Siu Lau Ho

Research output: Journal article publicationJournal articleAcademic researchpeer-review

74 Citations (Scopus)


A novel low-speed flux-modulated (FM) permanent-magnet (PM) motor that breaks the traditional design rule, which stipulates that the number of stator pole pairs and the number of rotor pole pairs must be the same, is proposed. The FM motor has a special physical structure with iron segments in the air gap to modulate the magnetic field. In the design, the free space between adjacent stationary iron segments also acts as ventilating ducts to help improving the heat dissipation and ventilation of the motor. Its cogging torque is very small. In this paper, a rule for comparing the power density of electric motors is proposed. The performance of the FM motor is compared with those of a magnetic-geared PM motor, a traditional PM motor, and a fractional-slot PM motor by using magnetic field finite-element analysis.
Original languageEnglish
Article number5232842
Pages (from-to)127-134
Number of pages8
JournalIEEE Transactions on Magnetics
Issue number1
Publication statusPublished - 1 Jan 2010


  • Electric motor
  • Finite-element analysis
  • Flux modulation
  • Low-speed drive
  • Magnetic field
  • Power density
  • Ventilation

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Electronic, Optical and Magnetic Materials

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