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Title: Design Considerations of a Transverse Flux Machine for Direct-Drive Wind Turbine Applications

This paper presents the design considerations of a double-sided transverse flux machine (TFM) for direct-drive wind turbine applications. The proposed TFM has a modular structure with quasi-U stator cores and toroidal ring windings. The rotor is constructed with ferrite magnets in a flux-concentrating setup to achieve high air gap flux density. Pole number selection is critical in the design process of a TFM as it affects both the torque density and power factor under fixed magnetic and changing electrical loading. Several key design ratios are introduced to facilitate the initial design procedure. The effect of pole shaping on back-EMF and inductance is also analyzed. These investigations provide guidance toward the required design of a TFM for direct-drive applications. The analyses are carried out using analytical and three-dimensional finite element analysis (FEA). A proof-of-concept prototype was developed to experimentally validate the FEA results.
 [1] ;  [1] ;  [1] ;  [2] ;  [3]
  1. Univ. of Akron, OH (United States)
  2. North Carolina State Univ., Raleigh, NC (United States)
  3. National Renewable Energy Lab. (NREL), Golden, CO (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0093-9994
Grant/Contract Number:
Accepted Manuscript
Journal Name:
IEEE Transactions on Industry Applications
Additional Journal Information:
Journal Volume: 54; Journal Issue: 4; Journal ID: ISSN 0093-9994
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Country of Publication:
United States
17 WIND ENERGY; 24 POWER TRANSMISSION AND DISTRIBUTION; transverse flux machine; permanent magnet machine; design of electric machine; pole number selection; pole shaping; design ratio; wind generator; high torque density
OSTI Identifier: