Vibration anlysis of brushless doubly fed machines in the presence of rotor eccentricity

Salman Abdi Jalebi, Ehsan Abdi, Richard McMahon, Hamid Toshani

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15 Citations (Scopus)
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In this work, an analytical study has been performed on the Brushless Doubly Fed Machine's (BDFM) vibration due to the interaction of its fundamental magnetic fields, exerting bending forces in the back iron. The effects of rotor eccentricity on exacerbating the machine's vibration have been considered by assessing the stator back iron displacement function in the presence of rotor eccentricity. Finite element analysis is carried out for a 250 kW BDFM built in frame size D400 to validate the analytical methods. The stator back iron displacement is determined for an ideally-constructed machine as well as when the rotor has static and dynamic eccentricity. In addition, the prototype BDFM was tested at different operating conditions in order to examine its noise and vibration levels. A set of measurements was conducted to assess the main vibration component frequencies developed by the machine at different rotor speeds. It is shown that the main vibration components are created by bending set-up in the back iron, rotor eccentricity, and the components with time and space harmonic natures. The results obtained from finite element analysis and experimentally agree with the analytical theory of BDFM vibration.

Original languageEnglish
Article number9068430
Pages (from-to)1372-1380
Number of pages9
JournalIEEE Transactions on Energy Conversion
Issue number3
Early online dateApr 2020
Publication statusPublished - Sep 2020


  • Air gaps
  • Beam theory
  • Brushless Doubly Fed Machine (BDFM)
  • Finite element analysis
  • Iron
  • Rotor eccentricity
  • Rotor speed ripples
  • Rotors
  • Space harmonics
  • Stator windings
  • Time harmonics
  • Vibration analysis
  • Vibrations
  • Windings

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