The Potential for NdFeB Magnets in Electrical Machines and Other Permanent Magnet Excited Devices

  • D Howe
  • T S Birch
  • K J Mitchell


The potential for NdFeB magnets in various categories and topologies of permanent magnet excited machine, for applications ranging from spindle-drives for machine tools to the electrodynamic braking of high-speed railway vehicles, as well as in other magnetic devices, has been examined. Design strategies and CAD procedures have been established for brushed dc motors, brushless dc and ac motors, line-start synchronous motors, hybrid stepper motors, and generators. In addition, finite element procedures have been implemented on an IBM PC to aid the design of permanent magnet devices in general. Theoretical designs have been validated against tests on a number of prototype units, some of which are being developed further to be launched as commercial products. The work undertaken under CEAM has indicated that there is little doubt thet NdFeB will become the material of choice for many future designs.


Permanent Magnet Synchronous Motor Railway Vehicle NdFeB Magnet Prototype Motor 
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Copyright information

© ECSC, EEC, EAEC, Brussels and Luxembourg 1989

Authors and Affiliations

  • D Howe
    • 1
  • T S Birch
    • 1
  • K J Mitchell
    • 1
  1. 1.Department of Electronic & Electrical EngineeringUniversity of SheffieldSheffieldEngland

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