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Advanced optimization methods for fractional slot concentrated windings

Electrical Engineering volume 101, pages 103–120 (2019)Cite this article

Abstract

Usage of fractional slot concentrated windings (FSCWs) in electrical machines offers several advantages due to their simplicity and compactness. However, the magnetic field of FSCWs has more space harmonics, including sub-harmonics that lead to undesirable effects. High rotor losses, noise, vibrations and thermal problems are the main drawbacks caused by FSCWs. These disadvantages limit the suitability of this winding type for some applications. In order to improve winding performances, several methods and techniques have recently been developed and analysed. This paper provides an update of latest research activities in terms of optimization of FSCW machines. These include efforts to reduce only sub-harmonics, to simultaneously reduce sub- and high harmonics or to use a higher harmonic for rotor excitation in current-excited synchronous machines. Simplest and most effective methods are considered, and their functionalities are explained briefly. Moreover, the effectiveness of said optimization methods is shown by simulation and experimental results, obtained from various optimized FSCW machines.

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Authors and Affiliations

  1. FEAAM GmbH, Werner-Heisenberg-Weg 39, 85577, Munich, Germany

    Gurakuq Dajaku

  2. Continental Powertrain, Business Unit Hybrid Electric Vehicle, Sickingenstrasse 42-46, 10553, Berlin, Germany

    Sachar Spas

  3. Universitaet der Bundeswehr Muenchen, Werner-Heisenberg-Weg 39, 85577, Munich, Germany

    Dieter Gerling

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  1. Gurakuq Dajaku
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  2. Sachar Spas
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  3. Dieter Gerling
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Correspondence to Sachar Spas.

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Dajaku, G., Spas, S. & Gerling, D. Advanced optimization methods for fractional slot concentrated windings. Electr Eng 101, 103–120 (2019). https://doi.org/10.1007/s00202-019-00760-6

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  • DOI: https://doi.org/10.1007/s00202-019-00760-6

Keywords

  • Fractional slot concentrated winding
  • Losses
  • Radial force
  • Noise and vibrations
  • Efficiency
  • Optimization
  • Permanent magnet machines
  • Asynchronous machines
  • Current-excited synchronous machines