Influence of Permanent Magnet Characteristic Variability on the Wind Generator Operation

O. Kudrjavtsev 1 , A. Kallaste 1 , 2 , A. Kilk 1 , T. Vaimann 1 , 2  and S. Orlova 1 , 3
  • 1 Tallinn University of Technology, Department of Electrical Engineering, 5 Ehitajate Str., 19086 Tallinn, Estonia
  • 2 Aalto University, Department of Electrical Engineering and Automation, 5A Otakaari Str., 02150 Espoo, Finland
  • 3 Institute of Physical Energetics, 11 Krivu Str., LV-1006, Riga, Latvia


The paper discusses problems concerning the influence of permanent magnet material characteristics on the low-speed permanent magnet generator losses and output characteristics. The variability of the magnet material and its effect on the output parameters of the machine has been quantified. The characteristics of six different grades of neodymium permanent magnets have been measured and compared to the supplier specification data. The simulations of the generator have been carried out using transient finite element analysis. The results show that magnet materials from different suppliers have different characteristics, which have a significant influence on the generator output parameters, such as efficiency and power factor.

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