Comparative Analysis of Magnetic Slot Wedges Design for Increasing Performance of Railway Traction Motor

  • Liu, Huai-Cong (Dept. of Electrical and Electronic Engineering, Hanyang University) ;
  • Cho, Sooyoung (Dept. of Electrical and Electronic Engineering, Hanyang University) ;
  • Hong, Hyun-Seok (Dept. of Electrical and Electronic Engineering, Hanyang University) ;
  • Joo, Kyoung-Jin (Dept. of Electrical and Electronic Engineering, Hanyang University) ;
  • Ham, Sang-Hwan (Dept. of Electrical and Railway Engineering, Kyungil University) ;
  • Lee, Ju (Dept. of Electrical and Electronic Engineering, Hanyang University)
  • 투고 : 2017.01.13
  • 심사 : 2017.06.22
  • 발행 : 2017.11.01


This study focuses on the effects of using open stator slots in an interior permanent magnet traction motor with a magnetic slot wedge design in order to increase the power density at its base speed. In addition, such a configuration reduces the torque ripple under field-weakening conditions. Five different wedge models were selected, each of which was evaluated using a finite element analysis (FEA). Based on the initial model, we designed magnetic slot wedges for maximum back-EMF and minimum cogging torque. In addition, the d-q axis inductance was slightly altered due to the magnetic slot wedges. Finally, we analyzed the performance of a traction machine under field weakening control. Moreover, we have outlined the requirements for an ideal magnetic slot wedge design.


연구 과제 주관 기관 : National Research Foundation of Korea (NRF), Korea Institute of Energy Technology Evaluation and Planning (KETEP)


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